1
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Chandra A, Basu P, Raha S, Dhibar P, Bhattacharya S. Development of ruthenium complexes with S-donor ligands for application in synthesis, catalytic acceptorless alcohol dehydrogenation and crossed-aldol condensation. Dalton Trans 2024; 53:10675-10685. [PMID: 38860941 DOI: 10.1039/d4dt00985a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
The reaction of [Ru(dmso)4Cl2] with a potassium salt of four xanthate (RO-C(S)S-; R = Me, Et, iPr and tBu) ligands (depicted as Ln; n = 1-4) in hot methanol afforded a group of mixed-ligand complexes of type [Ru(Ln)2(dmso)2]. The crystal structures of all the four complexes have been determined, which show that the xanthate ligands are bound to the metal center forming four-membered chelates and dmso is coordinated through sulfur and they are mutually cis. The relative thermodynamic stability of this cis and the other possible trans-isomers of these complexes has been assessed with the help of DFT calculations, which have revealed that the cis-isomer is the more stable isomer. The coordinated dmso in the [Ru(Ln)2(dmso)2] complexes could be easily displaced by chelating bidentate ligands (depicted as L') to furnish complexes of type [Ru(Ln)2(L')], as demonstrated through isolation of two such complexes, viz. [Ru(L3)2(bpy)] and [Ru(L2)2(phen)] (bpy = 2,2'-bipyridine and phen = 1,10-phenanthroline). The crystal structure of [Ru(L3)2(bpy)] has been determined and the structure of [Ru(L2)2(phen)] has been optimized by the DFT method. The electronic spectra of the four [Ru(Ln)2(dmso)2] complexes and the two derivatives ([Ru(Ln)2(L')]; n = 3, L' = bpy; n = 2, L' = phen), recorded in dichloromethane solutions, show intense absorptions spanning the visible and ultraviolet regions, which have been analyzed by the TDDFT method. The [Ru(Ln)2(dmso)2] complexes are found to serve as efficient catalyst precursors for the acceptorless dehydrogenation of 2-propanol followed by crossed-aldol condensation with substituted benzaldehydes (and related aldehydes), using tert-butoxide as the co-catalyst, producing dibenzylideneacetone derivatives in good yields.
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Affiliation(s)
- Anushri Chandra
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata - 700032, India.
| | - Pousali Basu
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata - 700032, India.
| | - Shreya Raha
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata - 700032, India.
| | - Papu Dhibar
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata - 700032, India.
- Department of Chemistry, Brainware University, Kolkata 700 125, India
| | - Samaresh Bhattacharya
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata - 700032, India.
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2
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Gourkhede R, Kaur B, Kote BS, Balakrishna MS. Arene displacement, C-H activation and acetonitrile insertion reactions enabled by coordination of a functionalized iminophosphorane to a Ru II- p-cymene scaffold. Dalton Trans 2024; 53:10693-10703. [PMID: 38869430 DOI: 10.1039/d4dt00940a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
Abstract
Reaction of a sterically demanding iminophosphorano-phosphine, Ph2PCH2Ph2PNAr* (here onwards referred to as PCPNAr*; Ar* = 2,6-dibenzhydryl-4-methylphenyl), (1) with [Ru(η6-p-cymene)Cl2]2 yielded three different types of complex, [RuCl2{(η6-p-cymene)(PCPNAr*)-κ1-P}] (2), [RuCl{(P(O)CPNAr*)(κ2-N,C)(C-η6-arene)}] (3) and [RuCl{(POCPNAr*)(κ2-N,C-o)(C-η6-arene)}] (4), depending on the reaction conditions via CH activation, tethered η6-arene coordination, ortho-metallation or PN bond cleavage/rearrangement reactions. Interestingly, a similar reaction in CH3CN in the presence of AgBF4 resulted in the insertion of CH3CN into the PN bond to form a novel metallacycle [Ru(NCMe)3{(PC2PN(CH3)CNAr*)-κ3-N,N,P}][BF4]2 (5) containing 4- and 5-membered rings via an aza-Wittig type reaction. Complex 4 showed very good catalytic activity in the transfer hydrogenation of carbonyl compounds.
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Affiliation(s)
- Rani Gourkhede
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
| | - Bhupinder Kaur
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
| | - Basvaraj S Kote
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
| | - Maravanji S Balakrishna
- Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
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3
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Parui N, Mandal T, Maiti S, Dash J. Efficient Synthesis of Cyclohepta[b]indoles and Cyclohepta[b]indole-Indoline Conjugates via RCM, Hydrogenation, and Acid-Catalyzed Ring Expansion: A Biomimetic Approach. Chemistry 2024; 30:e202401059. [PMID: 38623002 DOI: 10.1002/chem.202401059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Accepted: 04/15/2024] [Indexed: 04/17/2024]
Abstract
Cyclohepta[b]indoles, prevalent in natural products and pharmaceuticals, are conventionally accessed via metal or Lewis acid-mediated cycloadditions with prefunctionalized substrates. Our study introduces an innovative sequential catalytic assembly for synthesizing cyclohepta[b]indoles from readily available isatin derivatives. The process involves three catalytic sequences: ring-closing metathesis, catalytic hydrogenation, and acid-catalyzed ring expansion. The RCM of 2,2-dialkene-3-oxindoles, formed by butenyl Grignard addition to 3-allyl-3-hydroxy-2-oxindoles, yields versatile spirocyclohexene-3-oxindole derivatives. These derivatives undergo further transformations, including dibromination, dihydroxylation, epoxidation, Wacker oxidation at the double bond. Hydrogenation of spirocyclohexene-3-oxindole yields spirocyclohexane-3-oxindoles. Their subsequent acid-catalyzed ring expansion/aromatization, dependent on the acid catalyst, results in either cyclohepta[b]indoles or cyclohepta[b]indole-indoline conjugates, adding a unique synthetic dimension. The utility of this methodology is exemplified through the synthesis of an A-FABP inhibitor, showcasing its potential in pharmaceutical applications.
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Affiliation(s)
- Nabin Parui
- School of chemical sciences, Indian Association for the Cultivation of Science, Jadavpur, 700032, Kolkata, India
| | - Tirtha Mandal
- School of chemical sciences, Indian Association for the Cultivation of Science, Jadavpur, 700032, Kolkata, India
| | - Sandip Maiti
- School of chemical sciences, Indian Association for the Cultivation of Science, Jadavpur, 700032, Kolkata, India
| | - Jyotirmayee Dash
- School of chemical sciences, Indian Association for the Cultivation of Science, Jadavpur, 700032, Kolkata, India
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4
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Snabilié DD, Ham R, Reek JNH, de Bruin B. Light Induced Cobalt(III) Carbene Radical Formation from Dimethyl Malonate As Carbene Precursor. Organometallics 2024; 43:1299-1307. [PMID: 38873572 PMCID: PMC11167645 DOI: 10.1021/acs.organomet.4c00127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 05/13/2024] [Accepted: 05/16/2024] [Indexed: 06/15/2024]
Abstract
Radical-type carbene transfer catalysis is an efficient method for the direct functionalization of C-H and C=C bonds. However, carbene radical complexes are currently formed via high-energy carbene precursors, such as diazo compounds or iodonium ylides. Many of these carbene precursors require additional synthetic steps, have an explosive nature, or generate halogenated waste. Consequently, the utilization of carbene radical catalysis is limited by specific carbene precursors that access the carbene radical intermediate. In this study, we generate a cobalt(III) carbene radical complex from dimethyl malonate, which is commercially available and bench-stable. EPR and NMR spectroscopy were used to identify the intermediates and showed that the cobalt(III) carbene radical complex is formed upon light irradiation. In the presence of styrene, carbene transfer occurred, forming cyclopropane as the product. With this photochemical method, we demonstrate that dimethyl malonate can be used as an alternative carbene precursor in the formation of a cobalt(III) carbene radical complex.
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Affiliation(s)
- Demi D. Snabilié
- Van ‘t Hoff Institute
for Molecular Sciences, University of Amsterdam,
Science Park 904, Amsterdam 1098 XH, The Netherlands
| | - Rens Ham
- Van ‘t Hoff Institute
for Molecular Sciences, University of Amsterdam,
Science Park 904, Amsterdam 1098 XH, The Netherlands
| | - Joost N. H. Reek
- Van ‘t Hoff Institute
for Molecular Sciences, University of Amsterdam,
Science Park 904, Amsterdam 1098 XH, The Netherlands
| | - Bas de Bruin
- Van ‘t Hoff Institute
for Molecular Sciences, University of Amsterdam,
Science Park 904, Amsterdam 1098 XH, The Netherlands
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5
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Pal A, Wong AR, Lamb JR. Chemically Recyclable, High Molar Mass Polyoxazolidinones via Ring-Opening Metathesis Polymerization. ACS Macro Lett 2024; 13:502-507. [PMID: 38625148 DOI: 10.1021/acsmacrolett.4c00147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
The development of robust methods for the synthesis of chemically recyclable polymers with tunable properties is necessary for the design of next-generation materials. Polyoxazolidinones (POxa), polymers with five-membered urethanes in their backbones, are an attractive target because they are strongly polar and have high thermal stability, but existing step-growth syntheses limit molar masses and methods to chemically recycle POxa to monomer are rare. Herein, we report the synthesis of high molar mass POxa via ring-opening metathesis polymerization of oxazolidinone-fused cyclooctenes. These novel polymers show <5% mass loss up to 382-411 °C and have tunable glass transition temperatures (14-48 °C) controlled by the side chain structure. We demonstrate facile chemical recycling to monomer and repolymerization despite moderately high monomer ring-strain energies, which we hypothesize are facilitated by the conformational restriction introduced by the fused oxazolidinone ring. This method represents the first chain growth synthesis of POxa and provides a versatile platform for the study and application of this emerging subclass of polyurethanes.
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Affiliation(s)
- Arpan Pal
- Department of Chemistry, University of Minnesota-Twin Cities, Minneapolis, Minnesota 55455, United States
| | - Allison R Wong
- Department of Chemistry, University of Minnesota-Twin Cities, Minneapolis, Minnesota 55455, United States
| | - Jessica R Lamb
- Department of Chemistry, University of Minnesota-Twin Cities, Minneapolis, Minnesota 55455, United States
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Liang J, Chen X, Chen J, Ma X, Song Q. Highly Stereoselective Synthesis of Multisubstituted Olefins from Alkynyl Tetracoordinate Borons and Iodonium Ylides via a Cyclic Intermediate. Org Lett 2024; 26:3872-3877. [PMID: 38678580 DOI: 10.1021/acs.orglett.4c01031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2024]
Abstract
We developed an intriguing and practical strategy for highly stereoselective assembly of multisubstituted olefins from alkynyl tetracoordinate boron species via a cyclic intermediate with 1,2-phenyl migration. We also developed a general method for the construction of deuterated trisubstituted alkenes from a cheap deuteration source, D2O, and the corresponding deuterated trisubstituted alkenes were obtained with excellent deuteration rates. This transformation features a novel reaction mechanism, exclusive stereoselectivity, and deuterated trisubstituted alkenes with excellent deuteration ratios.
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Affiliation(s)
- Jinchao Liang
- College of Materials Science and Engineering, Fuzhou University, Fuzhou, Fujian 350108, China
| | - Xin Chen
- College of Materials Science and Engineering, Fuzhou University, Fuzhou, Fujian 350108, China
| | - Jinglong Chen
- College of Materials Science and Engineering, Fuzhou University, Fuzhou, Fujian 350108, China
| | - Xingxing Ma
- Key Laboratory of Molecule Synthesis and Function Discovery, Fujian Province University, College of Chemistry at Fuzhou University, Fuzhou, Fujian 350108, China
| | - Qiuling Song
- Key Laboratory of Molecule Synthesis and Function Discovery, Fujian Province University, College of Chemistry at Fuzhou University, Fuzhou, Fujian 350108, China
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
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7
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Xie T, Chen SS, Li YY, Chen DF. Leveraging Electron Push-Pull Effect for Catalytic Polymerization and Degradation of a Cyclobutane Monomer System. Angew Chem Int Ed Engl 2024:e202405408. [PMID: 38728168 DOI: 10.1002/anie.202405408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 04/26/2024] [Accepted: 05/09/2024] [Indexed: 05/12/2024]
Abstract
Ring-opening polymerization (ROP) offers a striking solution to solve problems encountered in step-growth condensation polymerization, including precise control over molecular weight, molecular weight distribution, and topology. This has inspired our interest in ROP of cycloalkanes with an ultimate goal to rethink polyolefins, which clearly poses a number of challenges. Practicality of ROP of cycloalkanes is actually limited by their low polymerizability and elusive mechanisms which arise from significantly varied ring size and non-polar C-C bonds in monomers. In this work, by using Lewis acid/Brønsted base/C(sp3)-H initiator system previously developed in our laboratory, we focus on cyclobutanes and explore the positional and electronic effects of substituents on the ring, namely electron push-pull effect, in promoting controlled polymerization to afford densely functionalized poly(cyclobutanes), as well as catalytic degradation of obtained polymers for upcycling. More importantly, experiments and DFT calculations unveil considerable population of Lewis-acid-induced thermostabilized 1,4-zwitterions, which distinguish cyclobutanes from cyclopropanes and others. All these findings would shed light on catalytic synthesis and degradation of saturated all-carbon main-chain polymers, as well as small molecule transformations of cyclobutanes.
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Affiliation(s)
- Teng Xie
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Shu-Sen Chen
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Yang-Yang Li
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Dian-Feng Chen
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, China
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8
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Dupont J, Leal BC, Lozano P, Monteiro AL, Migowski P, Scholten JD. Ionic Liquids in Metal, Photo-, Electro-, and (Bio) Catalysis. Chem Rev 2024; 124:5227-5420. [PMID: 38661578 DOI: 10.1021/acs.chemrev.3c00379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Ionic liquids (ILs) have unique physicochemical properties that make them advantageous for catalysis, such as low vapor pressure, non-flammability, high thermal and chemical stabilities, and the ability to enhance the activity and stability of (bio)catalysts. ILs can improve the efficiency, selectivity, and sustainability of bio(transformations) by acting as activators of enzymes, selectively dissolving substrates and products, and reducing toxicity. They can also be recycled and reused multiple times without losing their effectiveness. ILs based on imidazolium cation are preferred for structural organization aspects, with a semiorganized layer surrounding the catalyst. ILs act as a container, providing a confined space that allows modulation of electronic and geometric effects, miscibility of reactants and products, and residence time of species. ILs can stabilize ionic and radical species and control the catalytic activity of dynamic processes. Supported IL phase (SILP) derivatives and polymeric ILs (PILs) are good options for molecular engineering of greener catalytic processes. The major factors governing metal, photo-, electro-, and biocatalysts in ILs are discussed in detail based on the vast literature available over the past two and a half decades. Catalytic reactions, ranging from hydrogenation and cross-coupling to oxidations, promoted by homogeneous and heterogeneous catalysts in both single and multiphase conditions, are extensively reviewed and discussed considering the knowledge accumulated until now.
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Affiliation(s)
- Jairton Dupont
- Institute of Chemistry - Universidade Federal do Rio Grande do Sul - UFRGS, Avenida Bento Gonçalves, 9500, Porto Alegre 91501-970 RS, Brasil
- Departamento de Bioquímica y Biología Molecular B e Inmunología, Facultad de Química, Universidad de Murcia, P.O. Box 4021, E-30100 Murcia, Spain
| | - Bárbara C Leal
- Institute of Chemistry - Universidade Federal do Rio Grande do Sul - UFRGS, Avenida Bento Gonçalves, 9500, Porto Alegre 91501-970 RS, Brasil
| | - Pedro Lozano
- Departamento de Bioquímica y Biología Molecular B e Inmunología, Facultad de Química, Universidad de Murcia, P.O. Box 4021, E-30100 Murcia, Spain
| | - Adriano L Monteiro
- Institute of Chemistry - Universidade Federal do Rio Grande do Sul - UFRGS, Avenida Bento Gonçalves, 9500, Porto Alegre 91501-970 RS, Brasil
| | - Pedro Migowski
- Institute of Chemistry - Universidade Federal do Rio Grande do Sul - UFRGS, Avenida Bento Gonçalves, 9500, Porto Alegre 91501-970 RS, Brasil
| | - Jackson D Scholten
- Institute of Chemistry - Universidade Federal do Rio Grande do Sul - UFRGS, Avenida Bento Gonçalves, 9500, Porto Alegre 91501-970 RS, Brasil
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9
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Sousa JAD, Sá JLDS, Carneiro JWDM, Matos JMED. Structural and thermodynamic insights into the coordination preference of norbornadiene with the initiator complex [RuCl 2(PPh 3) 2(piperidine)] in polymerization via olefin metathesis. Phys Chem Chem Phys 2024; 26:13164-13171. [PMID: 38630007 DOI: 10.1039/d3cp03349j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
The metathesis reaction has been an important tool in both organic and inorganic synthetic chemistry. More specifically in polymer chemistry, ring opening metathesis polymerization (ROMP), via the formation of an active metal-carbene species (MCHR), has been widely used. The elucidation of the mechanism for ROMP opened the way for the development of well-defined catalysts, suited to local conditions. In the present study, we employed density functional theory (DFT) to investigate three reaction pathways for the formation of a species capable of activating ROMP. The active species is formed from the [RuCl2(PPh3)2(pip)] complex in the presence of norbornadiene (NBD) and the carbene source ethyl diazoacetate (EDA). Formation of a hexacoordinated intermediate [RuCl2(PPh3)2(pip)(NBD)] is favored in the first step, with NBD doubly coordinated to the [RuCl2(PPh3)2(pip)] moiety. Analysis of donation (X → Ru) and back-donation (Ru → X) processes in the [RuCl2(PPh3)2(pip)(NBD)] complex shows that piperidine behaves as a σ donor, while NBD behaves as a π donor and the PPh3 groups act as π acceptors. The intensity of the orbital component is predominant in relation to the steric component in the complex. Thus, we propose that the reaction occurs through the formation of a hexacoordinated complex, followed by the dissociation of a PPh3 group, thus forming a complex where NBD is doubly coordinated to the metal center. Coordination of EDA leads finally to the catalyst capable of forming the metallocyclobutane intermediate required for the ROMP reaction.
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Affiliation(s)
- José Antonio de Sousa
- Centro de Ciências Naturais, Universidade Federal do Piauí, Teresina, PI, 64049-550, Brazil.
| | - José Luiz da Silva Sá
- Centro de Ciências Naturais, Universidade Estadual do Piauí, Teresina, PI, 64002-150, Brazil
| | - José Walkimar de Mesquita Carneiro
- Centro de Ciências Naturais, Universidade Estadual do Piauí, Teresina, PI, 64002-150, Brazil
- Instituto de Química, Universidade Federal Fluminense, Niterói, RJ, 24020-141, Brazil
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10
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Liu M, Yan N, Tian H, Li B, Zhao D. Ring Expansion toward Disila-carbocycles via Highly Selective C-Si/C-Si Bond Cross-Exchange. Angew Chem Int Ed Engl 2024; 63:e202319187. [PMID: 38388782 DOI: 10.1002/anie.202319187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 02/21/2024] [Accepted: 02/22/2024] [Indexed: 02/24/2024]
Abstract
Herein, we successfully inhibited the preferential homodimerization and C-Si/Si-H bond cross-exchange of benzosilacyclobutenes and monohydro-silacyclobutanes and achieved the first highly selective C-Si/C-Si bond cross-exchange reaction by deliberately tuning the Ni-catalytic system, which constitutes a powerful and atom-economical ring expansion method for preparing medium-sized cyclic compounds bearing two silicon atoms at the ring junction, which are otherwise inaccessible. The DFT calculation explicitly elucidated the pivotal role of Si-H bond at silacyclobutanes and the high ring strain of two substrates in realizing the two C-Si bonds cleavage and reformation in the catalytic cycle.
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Affiliation(s)
- Min Liu
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Nuo Yan
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Haowen Tian
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Bo Li
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Dongbing Zhao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
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11
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Liu F, Liu X. Amphiphilic Dendronized Copolymer-Encapsulated Au, Ag and Pd Nanoparticles for Catalysis in the 4-Nitrophenol Reduction and Suzuki-Miyaura Reactions. Polymers (Basel) 2024; 16:1080. [PMID: 38674999 PMCID: PMC11054709 DOI: 10.3390/polym16081080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 04/09/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024] Open
Abstract
The branched structures of dendronized polymers can provide good steric stabilization for metal nanoparticle catalysts. In this work, an amphiphilic dendronized copolymer containing hydrophilic branched triethylene glycol moieties and hydrophobic branched ferrocenyl moieties is designed and prepared by one-pot ring-opening metathesis polymerization, and is used as the stabilizer for metal (Au, Ag and Pd) nanoparticles. These metal nanoparticles (Au nanoparticles: 3.5 ± 3.0 nm; Ag nanoparticles: 7.2 ± 4.0 nm; Pd nanoparticles: 2.5 ± 1.0 nm) are found to be highly active in both the 4-nitrophenol reduction and Suzuki-Miyaura reactions. In the 4-nitrophenol reduction, Pd nanoparticles have the highest catalytic ability (TOF: 2060 h-1). In addition, Pd nanoparticles are also an efficient catalyst for Suzuki-Miyaura reactions (TOF: 1980 h-1) and possess good applicability for diverse substrates. The amphiphilic dendronized copolymer will open a new door for the development of efficient metal nanoparticle catalysts.
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Affiliation(s)
| | - Xiong Liu
- State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi 830017, China;
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12
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Liu B, Rodriguez J, J Kilgallon L, Wang W, Wang Y, Wang A, Dai Y, Nguyen HVT, Pentelute BL, Johnson JA. An organometallic swap strategy for bottlebrush polymer-protein conjugate synthesis. Chem Commun (Camb) 2024; 60:4238-4241. [PMID: 38529790 PMCID: PMC11008127 DOI: 10.1039/d4cc00293h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 03/18/2024] [Indexed: 03/27/2024]
Abstract
Polymer-protein bioconjugation offers a powerful strategy to alter the physical properties of proteins, and various synthetic polymer compositions and architectures have been investigated for this purpose. Nevertheless, conjugation of molecular bottlebrush polymers (BPs) to proteins remains an unsolved challenge due to the large size of BPs and a general lack of methods to transform the chain ends of BPs into functional groups suitable for bioconjugation. Here, we present a strategy to address this challenge in the context of BPs prepared by "graft-through" ring-opening metathesis polymerization (ROMP), one of the most powerful methods for BP synthesis. Quenching ROMP of PEGylated norbornene macromonomers with an activated enyne terminator facilitates the transformation of the BP Ru alkylidene chain ends into Pd oxidative addition complexes (OACs) for facile bioconjugation. This strategy is shown to be effective for the synthesis of two BP-protein conjugates (albumin and ERG), setting the stage for a new class of BP-protein conjugates for future therapeutic and imaging applications.
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Affiliation(s)
- Bin Liu
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA.
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA
| | - Jacob Rodriguez
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA.
| | - Landon J Kilgallon
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA.
| | - Wencong Wang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA.
| | - Yuyan Wang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA.
| | - Aiden Wang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA.
| | - Yutong Dai
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA.
| | - Hung V-T Nguyen
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA.
| | - Bradley L Pentelute
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA.
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA
- Broad Institute of MIT and Harvard, Massachusetts Institute of Technology Cambridge, MA, 02142, USA
| | - Jeremiah A Johnson
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA.
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA
- Broad Institute of MIT and Harvard, Massachusetts Institute of Technology Cambridge, MA, 02142, USA
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13
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Irie Y, Yokoshima S. Total Synthesis of Putative Melognine. J Am Chem Soc 2024; 146:9526-9531. [PMID: 38546412 DOI: 10.1021/jacs.4c02086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Total synthesis of melognine was accomplished. A 10-membered cyclic alkyne was prepared via an intramolecular SN2 reaction of a nosylamide. Enyne metathesis of the cyclic alkyne under an atmosphere of ethylene afforded a 1,3-diene. Intramolecular cycloaddition of a nitrone and an azomethine ylide with the 1,3-diene moiety constructed the characteristic highly fused skeleton. Further transformation, including ring-closing metathesis, resulted in the synthesis of melognine, whose NMR spectra did not match the reported data. Close inspection of the spectra of melognine in the literature suggested that the structure of melognine might be identical with that of a known alkaloid, melodinine L.
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Affiliation(s)
- Yui Irie
- Graduate School of Pharmaceutical Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
| | - Satoshi Yokoshima
- Graduate School of Pharmaceutical Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
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14
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Mahto AK, Kanupriya, Kumari S, Yar MS, Dewangan RP. Hydrocarbon stapled temporin-L analogue as potential antibacterial and antiendotoxin agents with enhanced protease stability. Bioorg Chem 2024; 145:107239. [PMID: 38428282 DOI: 10.1016/j.bioorg.2024.107239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 02/06/2024] [Accepted: 02/22/2024] [Indexed: 03/03/2024]
Abstract
Antimicrobial resistance (AMR) is a serious global concern and a huge burden on the healthcare system. Antimicrobial peptides (AMPs) are considered as a solution of AMR due to their membrane-lytic and intracellular mode of action and therefore resistance development against AMPs is less frequent. One such AMPs, temporin-L (TL) is a 13-mer peptide reported as a potent and broad-spectrum antibacterial agent with significant immunomodulatory activity. However, TL is toxic to human erythrocytes at their antibacterial concentrations and therefore various analogues were synthesized with potent antimicrobial activity and lower hemolytic activity. In this work, we have selected a non-toxic engineered analogue of TL (eTL) and performed hydrocarbon stapling of amino acid residues at i to i + 4 positions at different part of sequence. The synthesized peptides were investigated against both the gram-positive and gram-negative bacteria as well as methicillin resistant S. aureus, its MIC was measured in the concentrations range of 0.9-15.2 µM. All analogues were found equal or better antibacterial as compared to parent peptide. Interestingly one analogue eTL [5-9] was found to be non-cytotoxic and stable in presence of the human serum. Mode of action studies revealed membrane depolarizing and disruptive mode of action with live MRSA. Further in vivo studies of antimicrobial against MRSA infection and anti-endotoxin activities in mice model revealed potential activity of the stapled peptide analogue. Overall, this reports on stapled analogue of the AMPs highlights an important strategy for the development of new antibacterial therapeutics against AMR.
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Affiliation(s)
- Aman Kumar Mahto
- Department of Pharmaceutical Chemistry, School of Pharmaceutical Education and Research (SPER), Jamia Hamdard (Deemed to be University), New Delhi 110062, India
| | - Kanupriya
- Department of Pharmaceutical Chemistry, School of Pharmaceutical Education and Research (SPER), Jamia Hamdard (Deemed to be University), New Delhi 110062, India
| | - Shalini Kumari
- CSIR-Institute of Genomics and Integrative Biology (IGIB), Sukhdev Vihar, Mathura Road, New Delhi 110025, India
| | - Mohammad Shahar Yar
- Department of Pharmaceutical Chemistry, School of Pharmaceutical Education and Research (SPER), Jamia Hamdard (Deemed to be University), New Delhi 110062, India
| | - Rikeshwer Prasad Dewangan
- Department of Pharmaceutical Chemistry, School of Pharmaceutical Education and Research (SPER), Jamia Hamdard (Deemed to be University), New Delhi 110062, India.
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15
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Wilson DM, Driedger DJ, Liu DY, Keerthisinghe S, Hermann A, Bieniossek C, Linington RG, Britton RA. Targeted sampling of natural product space to identify bioactive natural product-like polyketide macrolides. Nat Commun 2024; 15:2534. [PMID: 38514617 PMCID: PMC10958047 DOI: 10.1038/s41467-024-46721-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 03/01/2024] [Indexed: 03/23/2024] Open
Abstract
Polyketide or polyketide-like macrolides (pMLs) continue to serve as a source of inspiration for drug discovery. However, their inherent structural and stereochemical complexity challenges efforts to explore related regions of chemical space more broadly. Here, we report a strategy termed the Targeted Sampling of Natural Product space (TSNaP) that is designed to identify and assess regions of chemical space bounded by this important class of molecules. Using TSNaP, a family of tetrahydrofuran-containing pMLs are computationally assembled from pML inspired building blocks to provide a large collection of natural product-like virtual pMLs. By scoring functional group and volumetric overlap against their natural counterparts, a collection of compounds are prioritized for targeted synthesis. Using a modular and stereoselective synthetic approach, a library of polyketide-like macrolides are prepared to sample these unpopulated regions of pML chemical space. Validation of this TSNaP approach by screening this library against a panel of whole-cell biological assays, reveals hit rates exceeding those typically encountered in small molecule libraries. This study suggests that the TSNaP approach may be more broadly useful for the design of improved chemical libraries for drug discovery.
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Affiliation(s)
- Darryl M Wilson
- Department of Chemistry, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada
| | - Daniel J Driedger
- Department of Chemistry, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada
| | - Dennis Y Liu
- Department of Chemistry, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada
| | - Sandra Keerthisinghe
- Center for High-Throughput Chemical Biology, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada
| | - Adrian Hermann
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070, Basel, Switzerland
| | - Christoph Bieniossek
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070, Basel, Switzerland
| | - Roger G Linington
- Department of Chemistry, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada.
- Center for High-Throughput Chemical Biology, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada.
| | - Robert A Britton
- Department of Chemistry, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada.
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16
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Lessard JJ, Mejia EB, Kim AJ, Zhang Z, Berkey MG, Medina-Barreto ZS, Ewoldt RH, Sottos NR, Moore JS. Unraveling Reactivity Differences: Room-Temperature Ring-Opening Metathesis Polymerization (ROMP) versus Frontal ROMP. J Am Chem Soc 2024; 146:7216-7221. [PMID: 38441481 DOI: 10.1021/jacs.4c01578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
In this study, we explore the distinct reactivity patterns between frontal ring-opening metathesis polymerization (FROMP) and room-temperature solventless ring-opening metathesis polymerization (ROMP). Despite their shared mechanism, we find that FROMP is less sensitive to inhibitor concentration than room-temperature ROMP. By increasing the initiator-to-monomer ratio for a fixed inhibitor/initiator quantity, we find reduction in the ROMP background reactivity at room temperature (i.e., increased resin pot life). At elevated temperatures where inhibitor dissociation prevails, accelerated frontal polymerization rates are observed because of the concentrated presence of the initiator. Surprisingly, the strategy of employing higher initiator loading enhances both pot life and front speeds, which leads to FROMP rates exceeding prior reported values by over 5 times. This counterintuitive behavior is attributed to an increase in the proximity of the inhibitor to the initiator within the bulk resin and to whether the temperature favors coordination or dissociation of the inhibitor. A rapid method was developed for assessing resin pot life, and a straightforward model for active initiator behavior was established. Modified resin systems enabled direct ink writing of robust thermoset structures at rates much faster than previously possible.
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Affiliation(s)
- Jacob J Lessard
- Beckman Institute for Advanced Science and Technology, Department of Chemistry, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States of America
| | - Edgar B Mejia
- Beckman Institute for Advanced Science and Technology, Department of Material Science and Engineering, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States of America
| | - Abbie J Kim
- Beckman Institute for Advanced Science and Technology, Department of Chemistry, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States of America
| | - Zhang Zhang
- Beckman Institute for Advanced Science and Technology, Department of Material Science and Engineering, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States of America
| | - Mya G Berkey
- Beckman Institute for Advanced Science and Technology, Department of Chemistry, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States of America
| | - Zina S Medina-Barreto
- Beckman Institute for Advanced Science and Technology, Department of Material Science and Engineering, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States of America
| | - Randy H Ewoldt
- Beckman Institute for Advanced Science and Technology, Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States of America
| | - Nancy R Sottos
- Beckman Institute for Advanced Science and Technology, Department of Material Science and Engineering, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States of America
| | - Jeffrey S Moore
- Beckman Institute for Advanced Science and Technology, Department of Chemistry, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States of America
- Beckman Institute for Advanced Science and Technology, Department of Material Science and Engineering, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, United States of America
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17
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Zou S, Zhao Z, Huang H. Enantioselective Ring-Closing Aminomethylamination of Allylic Aminodienes with Aminals Triggered by C-N Bond Metathesis. Org Lett 2024. [PMID: 38502801 DOI: 10.1021/acs.orglett.4c00641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
A conceptually novel strategy utilizing a cyclopalladated complex as an electrophile to activate the C-N bond for the C-N bond metathesis between allylamines and aminals is developed, which enables an efficient ring-closing aminomethylamination of allylic aminodienes and aminals. The reaction proceeds under mild reaction conditions and displays a remarkable scope. Utilizing a modified Trost-type diphosphine as the ligand, this method enables the efficient synthesis of 5-10-membered aminoallylated chiral N-heterocycles in good yields with high enantiomeric excess values.
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Affiliation(s)
- Suchen Zou
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Zeyu Zhao
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Hanmin Huang
- Key Laboratory of Precision and Intelligent Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
- Key Laboratory of Green and Precise Synthetic Chemistry and Applications, Ministry of Education, Huaibei Normal University, Huaibei, Anhui 235000, People's Republic of China
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18
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Masuda T, Ohyama K, Yoshimura A, Fuwa H. Total Synthesis of (-)-Enigmazole A by the Macrocyclization/Transannular Pyran Cyclization Strategy. Org Lett 2024; 26:2045-2050. [PMID: 38421804 DOI: 10.1021/acs.orglett.4c00290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
An 18-step synthesis of (-)-enigmazole A is herein disclosed. The present synthesis is based on a modular assembly of three building blocks of similar complexity, a macrocyclic ring-closing metathesis to forge the 18-membered macrocyclic skeleton, and a desilylative transannular oxa-Michael addition for stereoselective construction of the 2,6-cis-substituted tetrahydropyran ring.
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Affiliation(s)
- Taisei Masuda
- Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku Tokyo 112-8551, Japan
| | - Kyoya Ohyama
- Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku Tokyo 112-8551, Japan
| | - Atsushi Yoshimura
- Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku Tokyo 112-8551, Japan
| | - Haruhiko Fuwa
- Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku Tokyo 112-8551, Japan
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19
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Sato K, Nakagawa Y, Mori M, Takinoue M, Kinbara K. Transient control of lytic activity via a non-equilibrium chemical reaction system. NANOSCALE 2024. [PMID: 38465880 DOI: 10.1039/d3nr06626f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
The development of artificial non-equilibrium chemical reaction systems has recently attracted considerable attention as a new type of biomimetic. However, due to the lack of bioorthogonality, such reaction systems could not be linked to the regulation of any biological phenomena. Here, we have newly designed a non-equilibrium reaction system based on olefin metathesis to produce the Triton X-mimetic non-ionic amphiphile as a kinetic product. Using phospholipid vesicles encapsulating fluorescent dyes and red blood cells as cell models, we demonstrate that the developed chemical reaction system is applicable for transient control of the resulting lytic activity.
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Affiliation(s)
- Kohei Sato
- School of Life Science and Technology, International Research Frontiers Initiative, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
| | - Yume Nakagawa
- School of Life Science and Technology, International Research Frontiers Initiative, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
| | - Miki Mori
- School of Life Science and Technology, International Research Frontiers Initiative, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
| | - Masahiro Takinoue
- School of Life Science and Technology, International Research Frontiers Initiative, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
- Department of Computer Science, International Research Frontiers Initiative, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
- Living Systems Materialogy Research Group, International Research Frontiers Initiative, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
| | - Kazushi Kinbara
- School of Life Science and Technology, International Research Frontiers Initiative, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
- Living Systems Materialogy Research Group, International Research Frontiers Initiative, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
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20
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Pieper K, Bleith R, Köhler C, Mika R, Gansäuer A. A Flexible Synthesis of Polypropionates via Diastereodivergent Reductive Ring-Opening of Trisubstituted Secondary Glycidols. Angew Chem Int Ed Engl 2024; 63:e202317525. [PMID: 38108105 DOI: 10.1002/anie.202317525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 12/15/2023] [Accepted: 12/15/2023] [Indexed: 12/19/2023]
Abstract
Polypropionates, characterized by their alternating sequence of stereocenters bearing methyl- and hydroxy-groups, are structurally diverse natural products of utmost importance.[1] Herein, we introduce a novel concept approach towards polypropionate synthesis featuring a diastereodivergent reductive epoxide-opening as a key step. Readily available and stereochemically uniform trisubstituted sec-glycidols serve as branching points for the highly selective synthesis of all isomers of polypropionate building blocks with three or more consecutive stereocenters. Stereodiversification is accomplished by an unprecedented mechanism-control over the stereochemically complementary modification of the epoxide's tertiary C-atom with excellent control of regio- and stereoselectivity. Since our method is not only suited for the preparation of specific targets but also for compound libraries, it will have a great impact on polypropionate synthesis.
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Affiliation(s)
- Katharina Pieper
- Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany
| | - Robin Bleith
- Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany
| | - Christian Köhler
- Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany
| | - Regine Mika
- Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany
| | - Andreas Gansäuer
- Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, 53121, Bonn, Germany
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21
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Betschart L, Altmann KH. Total Synthesis of Isoxeniolide A. Angew Chem Int Ed Engl 2024; 63:e202315423. [PMID: 38118052 DOI: 10.1002/anie.202315423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 12/19/2023] [Accepted: 12/20/2023] [Indexed: 12/22/2023]
Abstract
Isoxeniolide A is a highly strained xenicane diterpenoid of marine origin. This natural product is representative for a subfamily of xenicanes incorporating an allylic hydroxy group in the nine-membered ring; members of this xenicane subfamily so far have not been targeted by total synthesis. Herein, we describe the first asymmetric total synthesis of isoxeniolide A. Key to forming the challenging E-configured cyclononene ring was a diastereoselective intramolecular Nozaki-Hiyama-Kishi reaction. Other important transformations include an enzymatic desymmetrization for absolute stereocontrol, a diastereoselective cuprate addition and the use of a bifunctional vinyl silane building block. Our strategy also permits access to the enantiomer of the natural product and holds potential to access a multitude of xenicane natural products and analogs for structure-activity relationship studies.
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Affiliation(s)
- Leo Betschart
- ETH Zurich, Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, HCI H405, Vladimir-Prelog-Weg 4, 8093, Zurich, Switzerland
| | - Karl-Heinz Altmann
- ETH Zurich, Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, HCI H405, Vladimir-Prelog-Weg 4, 8093, Zurich, Switzerland
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22
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Kellner-Rogers JS, Wang R, Lambert TH. Diazene-Catalyzed Oxidative Alkyl Halide-Olefin Metathesis. Org Lett 2024; 26:1078-1082. [PMID: 38295157 PMCID: PMC10947577 DOI: 10.1021/acs.orglett.3c04309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
Abstract
The first platform for oxidative alkyl halide-olefin metathesis is described. The procedure employs diazenes as catalysts, which effect the cyclization of alkenyl alkyl halides to generate cyclic olefins and carbonyl products. The synthesis of phenanthrene, coumarin, and quinolone derivatives is demonstrated as well as the potential to apply this strategy to other electrophiles.
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Affiliation(s)
| | - Rina Wang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
| | - Tristan H. Lambert
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
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23
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Baumann JE, Chung CP, Lalic G. Stereoselective Copper-Catalyzed Olefination of Imines. Angew Chem Int Ed Engl 2024; 63:e202316521. [PMID: 38100274 PMCID: PMC10977923 DOI: 10.1002/anie.202316521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 12/10/2023] [Accepted: 12/12/2023] [Indexed: 12/17/2023]
Abstract
Alkenes are an important class of organic molecules found among synthetic intermediates and bioactive compounds. They are commonly synthesized through stoichiometric Wittig-type olefination of carbonyls and imines, using ylides or their equivalents. Despite the importance of Wittig-type olefination reactions, their catalytic variants remain underdeveloped. We explored the use of transition metal catalysis to form ylide equivalents from readily available starting materials. Our investigation led to a new copper-catalyzed olefination of imines with alkenyl boronate esters as coupling partners. We identified a heterobimetallic complex, obtained by hydrocupration of the alkenyl boronate esters, as the key catalytic intermediate that serves as an ylide equivalent. The high E-selectivity observed in the reaction is due to the stereoselective addition of this intermediate to an imine, followed by stereospecific anti-elimination.
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Affiliation(s)
- James E Baumann
- Department of Chemistry, University of Washington, 109 Bagley Hall, 98195, Seattle, WA, USA
| | - Crystal P Chung
- Department of Chemistry, University of Washington, 109 Bagley Hall, 98195, Seattle, WA, USA
| | - Gojko Lalic
- Department of Chemistry, University of Washington, 109 Bagley Hall, 98195, Seattle, WA, USA
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24
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Wang JY, Stevens JM, Kariofillis SK, Tom MJ, Golden DL, Li J, Tabora JE, Parasram M, Shields BJ, Primer DN, Hao B, Del Valle D, DiSomma S, Furman A, Zipp GG, Melnikov S, Paulson J, Doyle AG. Identifying general reaction conditions by bandit optimization. Nature 2024; 626:1025-1033. [PMID: 38418912 DOI: 10.1038/s41586-024-07021-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 01/03/2024] [Indexed: 03/02/2024]
Abstract
Reaction conditions that are generally applicable to a wide variety of substrates are highly desired, especially in the pharmaceutical and chemical industries1-6. Although many approaches are available to evaluate the general applicability of developed conditions, a universal approach to efficiently discover these conditions during optimizations is rare. Here we report the design, implementation and application of reinforcement learning bandit optimization models7-10 to identify generally applicable conditions by efficient condition sampling and evaluation of experimental feedback. Performance benchmarking on existing datasets statistically showed high accuracies for identifying general conditions, with up to 31% improvement over baselines that mimic state-of-the-art optimization approaches. A palladium-catalysed imidazole C-H arylation reaction, an aniline amide coupling reaction and a phenol alkylation reaction were investigated experimentally to evaluate use cases and functionalities of the bandit optimization model in practice. In all three cases, the reaction conditions that were most generally applicable yet not well studied for the respective reaction were identified after surveying less than 15% of the expert-designed reaction space.
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Affiliation(s)
- Jason Y Wang
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Jason M Stevens
- Chemical Process Development, Bristol Myers Squibb, Summit, NJ, USA
| | - Stavros K Kariofillis
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
- Department of Chemistry, Columbia University, New York, NY, USA
| | - Mai-Jan Tom
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA
| | - Dung L Golden
- Chemical Process Development, Bristol Myers Squibb, Summit, NJ, USA
| | - Jun Li
- Chemical Process Development, Bristol Myers Squibb, New Brunswick, NJ, USA
| | - Jose E Tabora
- Chemical Process Development, Bristol Myers Squibb, New Brunswick, NJ, USA
| | - Marvin Parasram
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Department of Chemistry, New York University, New York, NY, USA
| | - Benjamin J Shields
- Department of Chemistry, Princeton University, Princeton, NJ, USA
- Molecular Structure and Design, Bristol Myers Squibb, Cambridge, MA, USA
| | - David N Primer
- Chemical Process Development, Bristol Myers Squibb, Summit, NJ, USA
- Loxo Oncology at Lilly, Louisville, CO, USA
| | - Bo Hao
- Janssen Research and Development, Spring House, PA, USA
| | - David Del Valle
- Chemical Process Development, Bristol Myers Squibb, New Brunswick, NJ, USA
| | - Stacey DiSomma
- Chemical Process Development, Bristol Myers Squibb, New Brunswick, NJ, USA
| | - Ariel Furman
- Chemical Process Development, Bristol Myers Squibb, New Brunswick, NJ, USA
| | - G Greg Zipp
- Discovery Synthesis, Bristol Myers Squibb, Princeton, NJ, USA
| | | | - James Paulson
- Chemical Process Development, Bristol Myers Squibb, New Brunswick, NJ, USA
| | - Abigail G Doyle
- Department of Chemistry, Princeton University, Princeton, NJ, USA.
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, USA.
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25
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Li K, Tran NV, Pan Y, Wang S, Jin Z, Chen G, Li S, Zheng J, Loh XJ, Li Z. Next-Generation Vitrimers Design through Theoretical Understanding and Computational Simulations. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2302816. [PMID: 38058273 PMCID: PMC10837359 DOI: 10.1002/advs.202302816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 09/03/2023] [Indexed: 12/08/2023]
Abstract
Vitrimers are an innovative class of polymers that boast a remarkable fusion of mechanical and dynamic features, complemented by the added benefit of end-of-life recyclability. This extraordinary blend of properties makes them highly attractive for a variety of applications, such as the automotive sector, soft robotics, and the aerospace industry. At their core, vitrimer materials consist of crosslinked covalent networks that have the ability to dynamically reorganize in response to external factors, including temperature changes, pressure variations, or shifts in pH levels. In this review, the aim is to delve into the latest advancements in the theoretical understanding and computational design of vitrimers. The review begins by offering an overview of the fundamental principles that underlie the behavior of these materials, encompassing their structures, dynamic behavior, and reaction mechanisms. Subsequently, recent progress in the computational design of vitrimers is explored, with a focus on the employment of molecular dynamics (MD)/Monte Carlo (MC) simulations and density functional theory (DFT) calculations. Last, the existing challenges and prospective directions for this field are critically analyzed, emphasizing the necessity for additional theoretical and computational advancements, coupled with experimental validation.
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Affiliation(s)
- Ke Li
- Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03, Singapore, 138634, Republic of Singapore
| | - Nam Van Tran
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Yuqing Pan
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Sheng Wang
- Institute of Sustainability for Chemicals, Energy and Environment (ISCE2), Agency for Science, Technology and Research (A*STAR), Singapore, 138634, Singapore
| | - Zhicheng Jin
- Laboratory for Biomaterials and Drug Delivery, The Department of Anesthesiology, Critical Care and Pain Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Guoliang Chen
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Shuzhou Li
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Jianwei Zheng
- Institute of High Performance Computing (IHPC), Agency for Science, Technology and Research (A*STAR), 1 Fusionopolis Way, #16-16 Connexis, Singapore, 138632, Republic of Singapore
| | - Xian Jun Loh
- Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03, Singapore, 138634, Republic of Singapore
- Institute of Sustainability for Chemicals, Energy and Environment (ISCE2), Agency for Science, Technology and Research (A*STAR), Singapore, 138634, Singapore
| | - Zibiao Li
- Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03, Singapore, 138634, Republic of Singapore
- Institute of Sustainability for Chemicals, Energy and Environment (ISCE2), Agency for Science, Technology and Research (A*STAR), Singapore, 138634, Singapore
- Department of Materials Science and Engineering, National University of Singapore, Singapore, 117576, Singapore
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26
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Li S, Qian C, Wu XN, Zhou S. Carbon-Atom Exchange between [MC 2] + (M = Os and Ir) and Methane: on the Thermodynamic and Dynamic Aspects. J Phys Chem A 2024; 128:792-798. [PMID: 38239066 DOI: 10.1021/acs.jpca.3c07961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
Abstract
Gas-phase reactions of [OsC2]+ and [IrC2]+ with methane at ambient temperature have been studied using quadrupole-ion trap mass spectrometry combined with quantum chemical calculations. Both [OsC2]+ and [IrC2]+ undergo carbon-atom exchange reactions with methane. The associated mechanisms for the two systems are found to be similar. The differences in the rates of carbon isotope exchange reactions of methane with [MC2]+ (M = Os and Ir) are explained by several factors like the energy barrier for the initial H3C-H bond breaking processes, the molecular dynamics, orbital interactions, and the H-binding energies of the pivotal steps. Besides, the number of participating valence orbitals might be one of the keys to regulate the rate in the key step. The present findings may provide useful ideas and inspiration for designing similar processes.
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Affiliation(s)
- Shihan Li
- College of Chemical and Biological Engineering, Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology, Zhejiang University, Hangzhou 310027, P. R. China
- Zhejiang Provincial Innovation Center of Advanced Chemicals Technology, Institute of Zhejiang University - Quzhou, Quzhou 324000, P.R. China
| | - Chao Qian
- College of Chemical and Biological Engineering, Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology, Zhejiang University, Hangzhou 310027, P. R. China
- Zhejiang Provincial Innovation Center of Advanced Chemicals Technology, Institute of Zhejiang University - Quzhou, Quzhou 324000, P.R. China
| | - Xiao-Nan Wu
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, China
| | - Shaodong Zhou
- College of Chemical and Biological Engineering, Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology, Zhejiang University, Hangzhou 310027, P. R. China
- Zhejiang Provincial Innovation Center of Advanced Chemicals Technology, Institute of Zhejiang University - Quzhou, Quzhou 324000, P.R. China
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27
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Wang Y, Deng J, Ressler AJ, Lin S. Electroreductive Radical Addition-Polar Cyclization Cascade to Access Cycloalkanes. Org Lett 2024; 26:116-121. [PMID: 38157449 PMCID: PMC11192528 DOI: 10.1021/acs.orglett.3c03722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
Compared with flat aromatic scaffolds, three-dimensional aliphatic ring systems feature high structural complexity and topological diversity and, thus, have received increasing attention in drug discovery. Herein, we describe a mild and general electrochemical method for the modular synthesis of structurally distinct cyclic compounds, including monocyclic alkanes, benzo-fused ring systems, and spirocycles, from readily available alkenes and alkyl halides via a radical-polar crossover mechanism.
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Affiliation(s)
- Yi Wang
- Department of Chemistry and Chemical Biology, Cornell University, New York 14853, United States
| | - Jiachen Deng
- Department of Chemistry and Chemical Biology, Cornell University, New York 14853, United States
| | - Andrew J. Ressler
- Department of Chemistry and Chemical Biology, Cornell University, New York 14853, United States
| | - Song Lin
- Department of Chemistry and Chemical Biology, Cornell University, New York 14853, United States
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28
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Artault M, Cantin T, Longuet M, Vitse K, Mbengo CDM, Guégan F, Michelet B, Martin-Mingot A, Thibaudeau S. Exploring Superacid-Promoted Skeletal Reorganization of Aliphatic Nitrogen-Containing Compounds. Angew Chem Int Ed Engl 2024; 63:e202316458. [PMID: 37984060 DOI: 10.1002/anie.202316458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/14/2023] [Accepted: 11/17/2023] [Indexed: 11/22/2023]
Abstract
Here we report a method to reorganize the core structure of aliphatic unsaturated nitrogen-containing substrates exploiting polyprotonation in superacid solutions. The superelectrophilic activation of N-isopropyl systems allows for the selective formal Csp3 -H activation/cyclization or homologation / functionalization of nitrogen-containing substrates. This study also reveals that this skeletal reorganization can be controlled through protonation interplay. The mechanism of this process involves an original sequence of C-N bond cleavage, isopropyl cation generation and subsequent C-N bond and C-C bond formation. This was demonstrated through in situ NMR analysis and labelling experiments, also confirmed by DFT calculations.
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Affiliation(s)
- Maxime Artault
- IC2MP UMR CNRS 7285, Université de Poitiers, 4 rue Michel Brunet, 86073, Poitiers cedex 9, France
| | - Thomas Cantin
- IC2MP UMR CNRS 7285, Université de Poitiers, 4 rue Michel Brunet, 86073, Poitiers cedex 9, France
| | - Mélissa Longuet
- IC2MP UMR CNRS 7285, Université de Poitiers, 4 rue Michel Brunet, 86073, Poitiers cedex 9, France
| | - Kassandra Vitse
- IC2MP UMR CNRS 7285, Université de Poitiers, 4 rue Michel Brunet, 86073, Poitiers cedex 9, France
| | | | - Frédéric Guégan
- IC2MP UMR CNRS 7285, Université de Poitiers, 4 rue Michel Brunet, 86073, Poitiers cedex 9, France
| | - Bastien Michelet
- IC2MP UMR CNRS 7285, Université de Poitiers, 4 rue Michel Brunet, 86073, Poitiers cedex 9, France
| | - Agnès Martin-Mingot
- IC2MP UMR CNRS 7285, Université de Poitiers, 4 rue Michel Brunet, 86073, Poitiers cedex 9, France
| | - Sébastien Thibaudeau
- IC2MP UMR CNRS 7285, Université de Poitiers, 4 rue Michel Brunet, 86073, Poitiers cedex 9, France
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29
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Mammadova GZ, Atioğlu Z, Akkurt M, Grigoriev MS, Volchkov NS, Azizova AN, Bhattarai A, Antonova AS. Crystal structure of [1,3-bis-(2,4,6-tri-methyl-phen-yl)imidazolidin-2-yl-idene]di-chlorido-(2-{[(2-methoxyeth-yl)(meth-yl)amino]-meth-yl}benzyl-idene)ruth-en-ium. Acta Crystallogr E Crystallogr Commun 2024; 80:50-53. [PMID: 38312164 PMCID: PMC10833371 DOI: 10.1107/s2056989023010381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 12/01/2023] [Indexed: 02/06/2024]
Abstract
The title compound, [RuCl2(C33H43N3O)], is an example of a new generation of N,N-dialkyl ruthenium catalysts with an N-Ru coordination bond as part of a six-membered chelate ring. The Ru atom has an Addison τ parameter of 0.244, which indicates a geometry inter-mediate between square-based pyramidal and trigonal-bipyramidal. The complex shows the usual trans arrangement of the two chlorides, with Ru-Cl bond lengths of 2.3515 (8) and 2.379 (7) Å, and a Cl-Ru-Cl angle of 158.02 (3)°. One of the chlorine atoms and the atoms of the 2-meth-oxy-N-methyl-N-[(2-methyl-phen-yl)meth-yl]ethane-1-amine group of the title complex display disorder over two positions in a 0.889 (2): 0.111 (2) ratio.
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Affiliation(s)
- Gunay Z. Mammadova
- Organic Chemistry Department, Baku State University, Z. Xalilov Str. 23, Az 1148 Baku, Azerbaijan
| | - Zeliha Atioğlu
- Department of Aircraft Electrics and Electronics, School of Applied Sciences, Cappadocia University, Mustafapaşa, 50420 Ürgüp, Nevşehir, Türkiye
| | - Mehmet Akkurt
- Department of Physics, Faculty of Sciences, Erciyes University, 38039 Kayseri, Türkiye
| | - Mikhail S. Grigoriev
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Leninsky pr. 31, bld. 4, Moscow 119071, Russian Federation
| | - Nikita S. Volchkov
- Organic Chemistry Department, Faculty of Science, RUDN University, Miklukho-Maklaya St., 6, Moscow 117198, Russian Federation
| | - Asmet N. Azizova
- Department of Synthesis of Biologically Active Compounds, Scientific Research Center, Azerbaijan Medical University, Samed Vurgun St. 167, Az 1022 Baku, Azerbaijan
| | - Ajaya Bhattarai
- Department of Chemistry, M.M.A.M.C (Tribhuvan University) Biratnagar, Nepal
| | - Alexandra S. Antonova
- Organic Chemistry Department, Faculty of Science, RUDN University, Miklukho-Maklaya St., 6, Moscow 117198, Russian Federation
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30
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Huang Y, Zhao C, Zhang B, Li H, Zhao J. Marriage of Organic and Grubbs Catalysts for Tandem Synthesis of Bottlebrush Polyesters. ACS Macro Lett 2023; 12:1711-1717. [PMID: 38039396 DOI: 10.1021/acsmacrolett.3c00695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2023]
Abstract
Bottlebrush polymers (BBPs) have gained wide attention for their special characters, such as rigid main/side chains, stemming from the exceedingly high graft density. This study aims to provide a simple synthetic approach to BBPs with polyester side chains by merging ring-opening alternating copolymerization (ROAP) and ring-opening metathesis polymerization (ROMP). A simple phosphazene base (tBuP1) is employed for the ROAP of phthalic anhydride and epoxide, after which Grubbs third-generation catalyst (G3) is added to in situ switch on ROMP of the macromonomer, i.e., norbornenyl-ended alternating polyester. The compatibility of tBuP1 with G3 and well-controlled ROMP is evidenced by DOSY-NMR of mixed catalysts, characterization of BBPs, and side-chain degradation. The method can also be extended to BBPs with one-step synthesized block copolyesters side chains. These results highlight the strength of the non-nucleophilic organobase catalyst for convenient construction of complex (degradable) polymers with compositional diversity.
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Affiliation(s)
- Yuan Huang
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, People's Republic of China
| | - Chenke Zhao
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, People's Republic of China
| | - Boru Zhang
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, People's Republic of China
| | - Heng Li
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, People's Republic of China
- College of Chemistry and Key Laboratory of Advanced Organic Functional Materials of Colleges and Universities of Hunan Province, Xiangtan University, Xiangtan 411105, People's Republic of China
| | - Junpeng Zhao
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, People's Republic of China
- Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, South China University of Technology, Guangzhou 510640, People's Republic of China
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31
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Adhikari AS, Majumdar N. Unconventional Reactivity of a Grubbs Catalyst: Hydroalkylation Overriding Metathesis. Org Lett 2023. [PMID: 38029292 DOI: 10.1021/acs.orglett.3c03456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
Unprecedented reactivity of a Grubbs catalyst has been disclosed in a reaction between vinyl azaarenes and alkenylnitriles under standard metathesis conditions. No metathesis was observed; only hydroalkylation products were obtained in high yields. The practical utility of this method has been demonstrated by the application of the products in useful transformations, e.g., the formation of cyclic iminoesters and highly challenging medium-sized carbocycles.
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Affiliation(s)
- Amit Singh Adhikari
- Medicinal and Process Chemistry Division, Central Drug Research Institute (CSIR), Sector 10, Jankipuram Extension, Sitapur Road, P.O. Box 173, Lucknow, Uttar Pradesh 226031, India
| | - Nilanjana Majumdar
- Medicinal and Process Chemistry Division, Central Drug Research Institute (CSIR), Sector 10, Jankipuram Extension, Sitapur Road, P.O. Box 173, Lucknow, Uttar Pradesh 226031, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India
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32
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Hyun SM, Marathianos A, Boeck PT, Ghiviriga I, Lester DW, Sumerlin BS, Veige AS. Influence of solvent on cyclic polynorbornene tacticity. Chem Commun (Camb) 2023; 59:13993-13996. [PMID: 37938062 DOI: 10.1039/d3cc04167k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
Tacticity is critical to polymer properties. The influence of solvent on tacticity in the catalytic synthesis of cyclic polynorbornene (c-PNB) is reported. In toluene cis,syndiotactic c-PNB forms; in THF, cis,syn/iso c-PNB forms.
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Affiliation(s)
- Sung-Min Hyun
- University of Florida, Department of Chemistry, Center for Catalysis, P.O. Box 117200, Gainesville, FL, 32611, USA.
| | - Arkadios Marathianos
- Polymer Characterization Research Technology Platform, University of Warwick, Coventry CV4 7AL, UK
| | - Parker T Boeck
- University of Florida, Department of Chemistry, Center for Catalysis, P.O. Box 117200, Gainesville, FL, 32611, USA.
- University of Florida, Department of Chemistry, George and Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science and Engineering, Gainesville, FL 32611, USA
| | - Ion Ghiviriga
- University of Florida, Department of Chemistry, Center for Catalysis, P.O. Box 117200, Gainesville, FL, 32611, USA.
| | - Daniel W Lester
- Polymer Characterization Research Technology Platform, University of Warwick, Coventry CV4 7AL, UK
| | - Brent S Sumerlin
- University of Florida, Department of Chemistry, George and Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science and Engineering, Gainesville, FL 32611, USA
| | - Adam S Veige
- University of Florida, Department of Chemistry, Center for Catalysis, P.O. Box 117200, Gainesville, FL, 32611, USA.
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33
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An T, Ryu H, Choi TL. Living Alternating Ring-Opening Metathesis Copolymerization of 2,3-Dihydrofuran to Provide Completely Degradable Polymers. Angew Chem Int Ed Engl 2023; 62:e202309632. [PMID: 37789610 DOI: 10.1002/anie.202309632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 10/02/2023] [Accepted: 10/02/2023] [Indexed: 10/05/2023]
Abstract
2,3-Dihydrofuran (DHF) has recently been gaining significant attention as a comonomer in metathesis polymerization, thanks to its ability to provide the resultant polymer backbones with stimuli-responsive degradability. In this report, we present living alternating copolymerization of DHF with less reactive endo-tricyclo[4.2.2.02,5 ]deca-3,9-dienes (TDs) and endo-oxonorbornenes (oxoNBs). By carefully controlling the reactivity of both the Ru initiators and the monomers, we have achieved outstanding A, B-alternation (up to 98 %) under near stoichiometric DHF loading conditions. Notably, we have also found that the use of a more sterically hindered Ru initiator helps to attain polymer backbones with higher DHF incorporation and superior A, B-alternation. While preserving the living characteristics of DHF copolymerization, as evidenced by controlled molecular weights (up to 73.9 kDa), narrow dispersities (down to 1.05), and block copolymer formation, our DHF copolymers could be broken down to a single repeat unit level under acidic conditions. 1 H NMR analysis of the model copolymer revealed that after 24 hours of degradation, up to 80 % of the initial polymer was transformed into a single small molecule product, and after purification, up to 66 % of the degradation product was retrieved. This study provides a versatile approach to improve the alternation and degradability of DHF copolymers.
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Affiliation(s)
- Taeyang An
- Department of Chemistry, Seoul National University, 08826, Seoul, Republic of Korea
| | - Hanseul Ryu
- Department of Chemistry, Seoul National University, 08826, Seoul, Republic of Korea
| | - Tae-Lim Choi
- Department of Materials, ETH Zürich, 8093, Zürich, Switzerland
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34
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Jayarani A, Deepa M, Khan HA, Koothradan FF, Yoganandhini S, Sreelakshmi V, Sivasankar C. Ruthenium-Catalyzed Chemo-Selective Carbene Insertion into C-H Bond of Styrene over Cyclopropanation: C-C Bond Formation. J Org Chem 2023; 88:15817-15831. [PMID: 37934176 DOI: 10.1021/acs.joc.3c01881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
The C-C bond formation reactions are important in organic synthesis. Heck reaction is known to arylate the terminal carbon of olefins; however, direct alkylation of the terminal carbon of olefin is limited. Herein, we report a novel ruthenium-catalyzed selective cross-coupling reaction of styrene and α-diazoesters to form a new C-C bond over cyclopropanation via the C-H insertion process for the first time. Using this novel methodology, a wide variety of substrates have been utilized and a variety of α-vinylated benzylic esters and densely functionalized olefins have been synthesized with good stereoselectivity under mild reaction conditions. The overall reaction process proceeds through the carbene insertion into styrene to form the desired products in good to excellent yields with proper stereoselectivity. The selective C-H inserted product, wide substrate scope, and excellent functional group tolerance are the best features of this work.
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Affiliation(s)
- Arumugam Jayarani
- Catalysis and Energy Laboratory, Department of Chemistry, Pondicherry University (A Central University), Puducherry, Puducherry 605014, India
| | - Masilamani Deepa
- Postgraduate and Research Department of Chemistry, Muthurangam Government Arts College, Vellore, Tamil Nadu 632002, India
| | - Hilal Ahmad Khan
- Catalysis and Energy Laboratory, Department of Chemistry, Pondicherry University (A Central University), Puducherry, Puducherry 605014, India
| | - Fathima Febin Koothradan
- Catalysis and Energy Laboratory, Department of Chemistry, Pondicherry University (A Central University), Puducherry, Puducherry 605014, India
| | - Sekar Yoganandhini
- Postgraduate and Research Department of Chemistry, Muthurangam Government Arts College, Vellore, Tamil Nadu 632002, India
| | - Vinod Sreelakshmi
- Catalysis and Energy Laboratory, Department of Chemistry, Pondicherry University (A Central University), Puducherry, Puducherry 605014, India
| | - Chinnappan Sivasankar
- Catalysis and Energy Laboratory, Department of Chemistry, Pondicherry University (A Central University), Puducherry, Puducherry 605014, India
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35
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Martínez JP, Trzaskowski B. An Anthracene-Thiolate-Ligated Ruthenium Complex: Computational Insights into Z-Stereoselective Cross Metathesis. J Phys Chem A 2023; 127:9465-9472. [PMID: 37916964 PMCID: PMC10658622 DOI: 10.1021/acs.jpca.3c05021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 09/26/2023] [Accepted: 09/29/2023] [Indexed: 11/03/2023]
Abstract
Stereoselective control of the cross metathesis of olefins is a crucial aspect of synthetic procedures. In this study, we utilized density functional theory methods to calculate thermodynamic and kinetic descriptors to explore the stereoselectivity of cross metathesis between allylbenzene and 2-butene-1,4-diyl diacetate. A ruthenium-based complex, characterized primarily by an anthracene-9-thiolate ligand, was designed in silico to completely restrict the E conformation of olefins through a bottom-bound mechanism. Our investigation of the kinetics of all feasible propagation routes demonstrated that Z-stereoisomers of metathesis products can be synthesized with an energy cost of only 13 kcal/mol. As a result, we encourage further research into the synthetic strategies outlined in this work.
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Affiliation(s)
- Juan Pablo Martínez
- Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097 Warszawa, Poland
| | - Bartosz Trzaskowski
- Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097 Warszawa, Poland
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36
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Wu X, Ren N, Tong G, Zhu X. Surface Chain-Transfer Ring-Opening Metathesis Polymerization. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:15740-15747. [PMID: 37901940 DOI: 10.1021/acs.langmuir.3c02328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2023]
Abstract
Ring-opening metathesis polymerization (ROMP) is a powerful method to graft various types of polymer chains to a given surface. While surface-initiated ROMP (SI-ROMP) serves as an efficient tool for surface modification and is therefore widely reported, the method requires grafting (1) the olefin substrate and (2) the metathesis catalyst to the surface prior to the polymerization with multiple synthetic and work up steps. To overcome this difficulty, we proposed the use of the chain-transfer reaction as an alternative method for surface modification. Terminal olefins are grafted to the surface without the need to graft the metathesis catalysts, and polymers with olefin backbones are polymerized and grafted simultaneously via both ROMP and chain transfer (cross-metathesis between olefins from backbones and surfaces). Compared to SI-ROMP, this surface-chain transfer ROMP (SC-ROMP) method avoids grafting the catalyst and growing polymer chains from the surface and could be achieved in a single step. Various types of surfaces like carbon nanotubes, carbon fibers, graphene nanosheets, and silica microspheres are used for demonstration. We envision that this work could bring a convenient and effective solution to surface modification via ROMP.
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Affiliation(s)
- Xinting Wu
- School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Ning Ren
- School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Gangsheng Tong
- School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
- Shanghai Aerospace Equipment Manufacturer Co. Ltd., Shanghai Engineering Research Center of Specialized Polymer Materials for Aerospace, 100 Huaning Road, Shanghai 200245, China
| | - Xinyuan Zhu
- School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
- Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
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37
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Li S, Feng S, Zhou Y, Liu C, Chen B, Xing X. Development of Highly Enantio- and Z-Selective Grubbs Catalysts via Controllable C-H Bond Activation. J Am Chem Soc 2023; 145:22745-22752. [PMID: 37800981 DOI: 10.1021/jacs.3c08420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/07/2023]
Abstract
Asymmetric olefin metathesis is a powerful strategy for stereocontrolled synthesis that allows the formation of chiral elements in conjunction with carbon-carbon double bonds. Here, we report a new series of cyclometalated stereogenic-at-Ru catalysts that enable highly efficient asymmetric ring opening/cross-metathesis (AROCM) and asymmetric ring-closing metathesis (ARCM) reactions. Single enantiomers of these catalysts with either right-handed or left-handed configurations at the Ru center can be easily accessed via highly stereoselective C-H bond activation-based cyclometalation. Right-handed chiral Ru catalysts enabled the Z- and enantioselective AROCM of a wide range of norbornenes and terminal alkenes, generating densely functionalized cyclopentanes with excellent stereo- and enantioselectivities (99:1 Z/E, up to 99% ee). Left-handed chiral Ru catalysts enabled the facile ARCM of sterically unhindered, all-terminal prochiral trienes, which had not been achieved by previous Ru catalysts, providing simple cyclic ethers and amides with tertiary or quaternary carbon stereocenters with excellent enantioselectivities (up to 99% ee).
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Affiliation(s)
- Shaofeng Li
- Shenzhen Grubbs Institute and Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Shijie Feng
- Shenzhen Grubbs Institute and Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yali Zhou
- Shenzhen Grubbs Institute and Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Chao Liu
- Shenzhen Grubbs Institute and Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Bo Chen
- Shenzhen Grubbs Institute and Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Xiangyou Xing
- Shenzhen Grubbs Institute and Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen 518055, China
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38
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Resendiz-Lara DA, Azhdari S, Gojzewski H, Gröschel AH, Wurm FR. Water-soluble polyphosphonate-based bottlebrush copolymers via aqueous ring-opening metathesis polymerization. Chem Sci 2023; 14:11273-11282. [PMID: 37860667 PMCID: PMC10583743 DOI: 10.1039/d3sc02649c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 09/26/2023] [Indexed: 10/21/2023] Open
Abstract
Ring-opening metathesis polymerization (ROMP) is a versatile method for synthesizing complex macromolecules from various functional monomers. In this work, we report the synthesis of water-soluble and degradable bottlebrush polymers, based on polyphosphoesters (PPEs) via ROMP. First, PPE-macromonomers were synthesized via organocatalytic anionic ring-opening polymerization of 2-ethyl-2-oxo-1,3,2-dioxaphospholane using N-(hydroxyethyl)-cis-5-norbornene-exo-2,3-dicarboximide as the initiator and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as the catalyst. The resulting norbornene-based macromonomers had degrees of polymerization (DPn) ranging from 25 to 243 and narrow molar mass dispersity (Đ ≤ 1.10). Subsequently, these macromonomers were used in ROMP with the Grubbs 3rd-generation bispyridyl complex (Ru-G3) to produce a library of well-defined bottlebrush polymers. The ROMP was carried out either in dioxane or in aqueous conditions, resulting in well-defined and water-soluble bottlebrush PPEs. Furthermore, a two-step protocol was employed to synthesize double hydrophilic diblock bottlebrush copolymers via ROMP in water at neutral pH-values. This general protocol enabled the direct combination of PPEs with ROMP to synthesize well-defined bottlebrush polymers and block copolymers in water. Degradation of the PPE side chains was proven resulting in low molar mass degradation products only. The biocompatible and biodegradable nature of PPEs makes this pathway promising for designing novel biomedical drug carriers or viscosity modifiers, as well as many other potential applications.
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Affiliation(s)
- Diego A Resendiz-Lara
- Sustainable Polymer Chemistry (SPC), Department of Molecules and Materials, MESA+ Institute for Nanotechnology, Faculty of Science and Technology, Universiteit Twente PO Box 217 7500 AE Enschede The Netherlands
| | - Suna Azhdari
- Sustainable Polymer Chemistry (SPC), Department of Molecules and Materials, MESA+ Institute for Nanotechnology, Faculty of Science and Technology, Universiteit Twente PO Box 217 7500 AE Enschede The Netherlands
- Physical Chemistry, University of Münster Corrensstraße 28-30 Münster 48149 Germany
| | - Hubert Gojzewski
- Sustainable Polymer Chemistry (SPC), Department of Molecules and Materials, MESA+ Institute for Nanotechnology, Faculty of Science and Technology, Universiteit Twente PO Box 217 7500 AE Enschede The Netherlands
| | - Andre H Gröschel
- Physical Chemistry, University of Münster Corrensstraße 28-30 Münster 48149 Germany
| | - Frederik R Wurm
- Sustainable Polymer Chemistry (SPC), Department of Molecules and Materials, MESA+ Institute for Nanotechnology, Faculty of Science and Technology, Universiteit Twente PO Box 217 7500 AE Enschede The Netherlands
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39
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Podchorodecka P, Dziuk B, Szostak R, Szostak M, Bisz E. IPr* Oxa - a new class of sterically-hindered, wingtip-flexible N,C-chelating oxazole-donor N-heterocyclic carbene ligands. Dalton Trans 2023; 52:13608-13617. [PMID: 37698540 DOI: 10.1039/d3dt02255b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
N-heterocyclic carbenes (NHCs) have emerged as a major direction in ancillary ligand development for stabilization of reactive metal centers in inorganic and organometallic chemistry. In particular, wingtip-flexible NHCs have attracted significant attention due to their unique ability to provide a sterically-demanding environment for transition metals in various oxidation states. Herein, we report a new class of sterically-hindered, wingtip-flexible NHC ligands that feature N,C-chelating oxazole donors. These ligands are readily accessible through a modular arylation of oxazole derivatives. We report their synthesis and complete structural and electronic characterization. The evaluation of steric, electron-donating and π-accepting properties and coordination chemistry to Ag(I), Pd(II) and Rh(I) is described. Preliminary studies of catalytic activity in Ag, Pd and Rh-catalyzed coupling and hydrosilylation reactions are presented. This study establishes the fluxional behavior of a freely-rotatable oxazole unit, wherein the oxazolyl ring adjusts to the steric and electronic environment of the metal center. Considering the tremendous impact of sterically-hindered NHCs and their potential to stabilize reactive metals by N-chelation, we expect that this class of NHC ligands will be of broad interest in inorganic and organometallic chemistry.
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Affiliation(s)
- Pamela Podchorodecka
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland.
| | - Błażej Dziuk
- Department of Chemistry, University of Science and Technology, Norwida 4/6, Wroclaw 50-373, Poland
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA.
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland.
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40
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Shen J, Xu Z, Yang S, Li S, Jiang J, Zhang YQ. Quaternary Stereocenters via Catalytic Enantioconvergent Allylation of Epoxides. J Am Chem Soc 2023; 145:21122-21131. [PMID: 37722078 DOI: 10.1021/jacs.3c08188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/20/2023]
Abstract
The development of catalytic and enantioselective transformations for the synthesis of all-carbon quaternary stereocenters has long been recognized as a significant challenge in organic synthesis. While considerable progress has been made in asymmetric allylations, their potential to functionalize the commonly used synthon, epoxide, remains largely underexplored. Here we demonstrate the first highly regio- and enantioselective allylation of epoxides that delivers a range of quaternary stereocenters in the face of potentially problematic elimination and protonation reactions. The reaction proceeds via a radical approach under mild conditions and benefits from the use of earth-abundant titanium with a highly sophisticated salen ligand, which facilitates remarkable enantiocontrol and suppresses undesired side reactions. The resulting allylation products are multifunctional building blocks that can be elaborated chemo- and stereoselectively to a broad array of stereodefined structural motifs.
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Affiliation(s)
- Jian Shen
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
| | - Zhongyun Xu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
| | - Shuo Yang
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
| | - Shengxiao Li
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
| | - Jie Jiang
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
| | - Yong-Qiang Zhang
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
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41
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Smith LB, Armstrong RJ, Hou J, Smith E, Sze M, Sterling AJ, Smith A, Duarte F, Donohoe TJ. Redox Reorganization: Aluminium Promoted 1,5-Hydride Shifts Allow the Controlled Synthesis of Multisubstituted Cyclohexenes. Angew Chem Int Ed Engl 2023; 62:e202307424. [PMID: 37358307 PMCID: PMC10953022 DOI: 10.1002/anie.202307424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/21/2023] [Accepted: 06/26/2023] [Indexed: 06/27/2023]
Abstract
An efficient synthesis of cyclohexenes has been achieved from easily accessible tetrahydropyrans via a tandem 1,5-hydride shift-aldol condensation. We discovered that readily available aluminium reagents, e.g. Al2 O3 or Al(Ot Bu)3 are essential for this process, promoting the 1,5-hydride shift with complete regio- and enantiospecificity (in stark contrast to results obtained under basic conditions). The mild conditions, coupled with multiple methods available to access the tetrahydropyran starting materials makes this a versatile method with exceptional functional group tolerance. A wide range of cyclohexenes (>40 examples) have been prepared, many in enantiopure form, showing our ability to selectively install a substituent at each position around the newly forged cyclohexene ring. Experimental and computational studies revealed that aluminium serves a dual role in facilitating the hydride shift, activating both the alkoxide nucleophile and the electrophilic carbonyl group.
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Affiliation(s)
- Lewis B. Smith
- Chemistry Research LaboratoryUniversity of OxfordOX1 3TAOxfordUK
| | - Roly J. Armstrong
- Chemistry Research LaboratoryUniversity of OxfordOX1 3TAOxfordUK
- School of Natural and Environmental SciencesNewcastle UniversityNE1 7RUNewcastle Upon TyneUK
| | - Jingyan Hou
- Chemistry Research LaboratoryUniversity of OxfordOX1 3TAOxfordUK
| | - Edward Smith
- Chemistry Research LaboratoryUniversity of OxfordOX1 3TAOxfordUK
| | - Ming Sze
- Chemistry Research LaboratoryUniversity of OxfordOX1 3TAOxfordUK
| | | | - Alex Smith
- Syngenta, Jealott's Hill International Research CentreRG42 6EYBracknellBerkshireUK
| | - Fernanda Duarte
- Chemistry Research LaboratoryUniversity of OxfordOX1 3TAOxfordUK
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42
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Mandal A, Pal S, Kilbinger AFM. Controlled Ring Opening Metathesis Polymerization of a New Monomer: On Switching the Solvent-Water-Soluble Homopolymers to Degradable Copolymers. Macromol Rapid Commun 2023; 44:e2300218. [PMID: 37435988 DOI: 10.1002/marc.202300218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 06/12/2023] [Accepted: 06/25/2023] [Indexed: 07/13/2023]
Abstract
A new heterocyclic monomer is developed via simple Diels-Alder reaction which is reluctant to polymerize in dichloromethane (DCM) whereas undergoes facile polymerization in tetrahydrofuran with excellent control over molecular weight (Mn ) and dispersities (Đ) using Grubbs' third generation catalyst (G3). The deprotection of the tert-butoxycarbonyl group from the polymeric backbone yielded a water-soluble ring opening metathesis polymerization (ROMP) polymer easily. Moreover, in DCM this new monomer copolymerizes with 2,3-dihydrofuran under catalytic living ROMP conditions to give backbone degradable polymers. All the synthesized polymers are characterized by size exclusion chromatography (SEC) and nuclear magnetic resonance (NMR) spectroscopy. It is believed that this new route to water soluble ROMP homopolymers as well as the cost-effective and environmentally friendly route to degradable copolymers and block-copolymers could find applications in biomedicine in the near future.
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Affiliation(s)
- Ankita Mandal
- Department of Chemistry, University of Fribourg, Fribourg, CH-1700, Switzerland
| | - Subhajit Pal
- Department of Chemistry, University of Fribourg, Fribourg, CH-1700, Switzerland
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43
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Mukherjee A, Datta S, Richmond MG, Bhattacharya S. Ruthenium complexes of 1,4-diazabutadiene ligands with a cis-RuCl 2 moiety for catalytic acceptorless dehydrogenation of alcohols: DFT evidence of chemically non-innocent ligand participation. RSC Adv 2023; 13:25660-25672. [PMID: 37649575 PMCID: PMC10463240 DOI: 10.1039/d3ra04750d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Accepted: 08/07/2023] [Indexed: 09/01/2023] Open
Abstract
The acceptorless dehydrogenative coupling (ADC) of primary alcohols to esters by diazabutadiene-coordinated ruthenium compounds is reported. Treatment of cis-Ru(dmso)4Cl2 in acetone at 56 °C with different 1,4-diazabutadienes [p-XC6H4N[double bond, length as m-dash]C(H)(H)C[double bond, length as m-dash]NC6H4X-p; X = H, CH3, OCH3, and Cl; abbreviated as DAB-X], gives trans-Ru[κ2-N,N-DAB-X]2Cl2 as the kinetic product of substitution. Heating these products in o-xylene at 144 °C gives the thermodynamically favored cis-Ru[κ2-N,N-DAB-X]2Cl2 isomers. Electronic structure calculations confirm the greater stability of the cis diastereomer. The molecular structures for each pair of geometric isomers have been determined by X-ray diffraction analyses. Cyclic voltammetry experiments on the complexes show an oxidative response and a reductive response within 0.50 to 0.93 V and -0.76 to -1.24 V vs. SCE respectively. The cis-Ru[κ2-N,N-DAB-X]2Cl2 complexes function as catalyst precursors for the acceptorless dehydrogenative coupling of primary alcohols to H2 and homo- and cross-coupled esters. When 1,4-butanediol and 1,5-pentanediol are employed as substrates, lactones and hydroxyaldehydes are produced as the major dehydrogenation products, while secondary alcohols afforded ketones in excellent yields. The mechanism for the dehydrogenation of benzyl alcohol to benzyl benzoate and H2 using cis-Ru[κ2-N,N-DAB-H]2Cl2 (cis-1) as a catalyst precursor was investigated by DFT calculations. The data support a catalytic cycle that involves the four-coordinate species Ru[κ2-N,N-DAB-H][κ1-N-DAB-H](κ1-OCH2Ph) whose protonated κ1-diazabutadiene moiety functions as a chemically non-innocent ligand that facilitates a β-hydrogen elimination from the κ1-O-benzoxide ligand to give the corresponding hydride HRu[κ2-N,N-DAB-H][κ1-N-DAB-H](κ2-O,C-benzaldehyde). H2 production follows a Noyori-type elimination to give (H2)Ru[κ2-N,N-DAB-H][κ1-N-DAB-H](κ1-O-benzaldehyde) as an intermediate in the catalytic cycle.
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Affiliation(s)
- Aparajita Mukherjee
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University Kolkata 700 032 India
| | - Sayanti Datta
- Department of Chemistry, Brainware University Kolkata 700 125 India
| | | | - Samaresh Bhattacharya
- Department of Chemistry, Inorganic Chemistry Section, Jadavpur University Kolkata 700 032 India
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44
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Wang C, Zhang S, Yuan T, Jimoh AA, Abreu M, Shan C, Wojtas L, Xing Y, Hong X, Shi X. Triazole-modified Ru-carbene complexes: A valid olefin metathesis pre-catalyst for dynamic covalent chemistry via C=C bond formation. CHEM CATALYSIS 2023; 3:100678. [PMID: 37873035 PMCID: PMC10588561 DOI: 10.1016/j.checat.2023.100678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
The 1,2,3-triazole coordinated ruthenium carbene complexes (TA-Ru) were reported for the first time as a new class of modified Grubbs catalyst to achieve challenging olefin metathesis at higher temperatures without catalyst decomposition. Previously reported N-tethered Ru-carbene complexes all suffered from rapid cis/trans isomerization, causing significantly reduced catalyst reactivity. These new TA-Ru complexes hold the active trans-dichloro conformation even at 80 °C, allowing effective olefin metathesis for challenging substrates. With this new TA-Ru catalyst, cross-metathesis (CM), ring-closing metathesis (RCM) and dynamic covalent chemistry (DCvC) were achieved. Excitingly, the reactivity of TA-Ru prevails all previously reported N-coordinated Ru-carbene precatalysts, Grubbs II, and Hoveyda-Grubbs, making the TA-Ru a transformative catalytic system in olefin catalysis.
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Affiliation(s)
- Chenhuan Wang
- Department of Chemistry, University of South Florida, Tampa, FL, USA
| | - Shuyao Zhang
- Department of Chemistry, University of South Florida, Tampa, FL, USA
| | - Teng Yuan
- Department of Chemistry, University of South Florida, Tampa, FL, USA
| | - Abiola Azee Jimoh
- Department of Chemistry, University of South Florida, Tampa, FL, USA
| | - Maxwell Abreu
- Department of Chemistry, University of South Florida, Tampa, FL, USA
| | - Chuan Shan
- Department of Chemistry, University of South Florida, Tampa, FL, USA
| | - Lukasz Wojtas
- Department of Chemistry, University of South Florida, Tampa, FL, USA
| | | | - Xin Hong
- Department of Chemistry, Zhejiang University, China
| | - Xiaodong Shi
- Department of Chemistry, University of South Florida, Tampa, FL, USA
- Lead contact
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45
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Sui X, Wang C, Gutekunst WR. Sequestration of Ruthenium Residues via Efficient Fluorous-enyne Termination. Polym Chem 2023; 14:3160-3165. [PMID: 38269330 PMCID: PMC10805442 DOI: 10.1039/d3py00456b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
The creation of polymers without metal contamination remains a significant challenge for metathesis-based polymerization techniques and has complicated applications in biomedical and electronic applications. This communication reports a new approach for the removal of ruthenium byproducts through the design of an enyne terminator for metathesis polymerization that contains a fluorous tag. Upon reaction of a living polymer chain with the enyne, the ruthenium center is captured as a stable sulfur-chelated complex that can be efficiently removed after a single filtration through a fluorous cartridge. Levels of ruthenium residues as determined by ICP-MS were found to depend on the monomer structure, eluting solvent, and the degree of polymerization targeted. Ruthenium residues were minimized to low ppm levels (4-75 ppm) for most samples examined and also led to the improved thermal stability of the final materials. This represents the most efficient single method for removal of ruthenium residues from metathesis polymerization products.
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Affiliation(s)
- Xuelin Sui
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlanta Drive NW, Atlanta, Georgia 30332, United States
| | - Chenxiao Wang
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlanta Drive NW, Atlanta, Georgia 30332, United States
| | - Will R Gutekunst
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlanta Drive NW, Atlanta, Georgia 30332, United States
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46
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Huang W, Jackstell R, Franke R, Beller M. Towards "homeopathic" palladium-catalysed alkoxycarbonylation of aliphatic and aromatic olefins. Chem Commun (Camb) 2023. [PMID: 37449386 DOI: 10.1039/d3cc02277c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
Palladium-catalysed alkoxycarbonylation of alkenes allows for atom-efficient synthesis of esters from easily available alkenes in an industrially viable manner. One of the major costs associated with this process is the consumption of the catalyst system. Hence, for economic and ecologic reasons it is desirable to minimize the amount of metal and ligands wherever possible. Herein, we report "a homeopathic" palladium-catalysed alkoxycarbonylation of olefins under comparably mild conditions. The key to success is the homemade ligand LIKATphos providing good to excellent yields of ester products with catalyst turnover numbers in the range of 106.
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Affiliation(s)
- Weiheng Huang
- Leibniz-Institut für Katalyse e. V., Albert-Einstein-Straße 29a, Rostock 18059, Germany.
| | - Ralf Jackstell
- Leibniz-Institut für Katalyse e. V., Albert-Einstein-Straße 29a, Rostock 18059, Germany.
| | - Robert Franke
- Evonik Industries AG, Paul-Baumann-Strase. 1, 45772 Marl, Germany
- Lehrstuhl für Theoretische Chemie, Bochum 44780, Germany
| | - Matthias Beller
- Leibniz-Institut für Katalyse e. V., Albert-Einstein-Straße 29a, Rostock 18059, Germany.
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47
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Hanzl L, Vinklárek J, Dostál L, Císařová I, Litecká M, Honzíček J. Stabilization of propene molybdenum and tungsten half-sandwich complexes by intramolecular coordination of a thioether function. RSC Adv 2023; 13:19746-19756. [PMID: 37396830 PMCID: PMC10311468 DOI: 10.1039/d3ra03383j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Accepted: 06/22/2023] [Indexed: 07/04/2023] Open
Abstract
This study reports the stabilizing effect of an intramolecularly coordinated thioether function in propene complexes of the general formula [{η5:κS-C5H4(CH2)2SR}M(CO)2(η2-C2H3Me)][BF4] (M = Mo, W; R = Et, Ph). They are formed by protonation of allyl analogues [{η5-C5H4(CH2)2SR}M(CO)2(η3-C3H5)] by tetrafluoroboric acid in non-coordinating solvents. In contrast to analogues with unsubstituted Cp ligands, these propene complexes are isolable in a pure form and characterized by NMR spectroscopy. The molybdenum compounds are stable at low temperature and the propene ligand can easily be exchanged by thioethers or acetonitrile. Several representatives of the reaction products were characterized by X-ray structure analysis. The stabilization effect in tungsten complexes [{η5:κS-C5H4(CH2)2SR}W(CO)2(η2-C2H3Me)][BF4] (R = Et, Ph) was unusually high. The compounds are long-term stable at room temperature and do not undergo ligand exchange reactions even with strong chelators such as 1,10-phenanthroline. The molecular structure of the tungsten propene complex was confirmed by X-ray diffraction analysis on a single crystal.
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Affiliation(s)
- Lukáš Hanzl
- Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice Studentská 573 532 10 Pardubice Czech Republic
| | - Jaromír Vinklárek
- Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice Studentská 573 532 10 Pardubice Czech Republic
| | - Libor Dostál
- Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice Studentská 573 532 10 Pardubice Czech Republic
| | - Ivana Císařová
- Department of Inorganic Chemistry, Faculty of Science, Charles University in Prague Hlavova 2030/8 128 43 Prague 2 Czech Republic
| | - Miroslava Litecká
- Department of Materials Chemistry, Institute of Inorganic Chemistry of the CAS Husinec-Řež 1001 25068 Řež Czech Republic
| | - Jan Honzíček
- Institute of Chemistry and Technology of Macromolecular Materials, Faculty of Chemical Technology, University of Pardubice Studentská 573 532 10 Pardubice Czech Republic
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48
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Kempel S, Hsu TW, Nicholson JL, Michaudel Q. cis-Selective Acyclic Diene Metathesis Polymerization of α, ω-Dienes. J Am Chem Soc 2023; 145:12459-12464. [PMID: 37255463 PMCID: PMC10330887 DOI: 10.1021/jacs.3c03978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Indexed: 06/01/2023]
Abstract
The cis/trans stereochemistry of repeating alkenes in polymers provides a powerful handle to modulate the thermal and mechanical properties of these soft materials, but synthetic methods to precisely dictate this parameter remain scarce. We report herein a cis-selective acyclic diene metathesis (ADMET) polymerization of readily available α,ω-diene monomers with high functional group tolerance. Identification of a highly stereoselective cyclometalated Ru catalyst allowed the synthesis of a broad array of polymers with cis contents up to 99%. This platform was leveraged to study the impact of the cis geometry on the thermal and mechanical properties of polyalkenamers, including an ABA triblock copolymer synthesized via extension of a cis-rich telechelic polyoctenamer with d,l-lactide. These results suggest that cis-selective ADMET affords an efficient strategy to tune the properties of a variety of polymers.
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Affiliation(s)
- Samuel
J. Kempel
- Department
of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Ting-Wei Hsu
- Department
of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Jake L. Nicholson
- Department
of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Quentin Michaudel
- Department
of Chemistry, Texas A&M University, College Station, Texas 77843, United States
- Department
of Materials Science & Engineering, Texas A&M University, College Station, Texas 77843, United States
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49
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Mandal A, Kilbinger AFM. Catalytic living ROMP: block copolymers from macro-chain transfer agents. Polym Chem 2023; 14:2797-2802. [PMID: 37325179 PMCID: PMC10262279 DOI: 10.1039/d3py00387f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 05/16/2023] [Indexed: 06/17/2023]
Abstract
Vinyl ether based macro-chain transfer agents (m-CTAs) are used to produce different di or tri-block copolymers under catalytic living ROMP conditions. Polystyrene (PS) vinyl ether m-CTA and polycaprolactone (PCL) or polylactide vinyl ether (PLA) m-CTAs are synthesized straightforwardly via ATRP and ROP respectively. Regioselectivity as well as the high metathesis activity of these m-CTAs enabled us to synthesise a range of metathesis-based A-B diblock copolymers with controlled dispersities (Đ < 1.4). In this manner, PS-ROMP (here, ROMP refers to a poly(MNI-co-DHF) block), PCL-ROMP and PLA-ROMP were synthesized using substoichiometric amounts of ruthenium complex in a living fashion. Also, a more complex PEG-PCL-ROMP tri-block terpolymer was obtained catalytically. All block copolymers were characterized by SEC and DOSY NMR spectroscopy. We believe that this methodology of using macro-chain transfer agents to prepare degradable ROMP polymers under catalytic living ROMP conditions will find applications in biomedicine.
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Affiliation(s)
- Ankita Mandal
- Department of chemistry, University of Fribourg Chemin du Musée 9 1700 Fribourg Switzerland
| | - Andreas F M Kilbinger
- Department of chemistry, University of Fribourg Chemin du Musée 9 1700 Fribourg Switzerland
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50
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Liang Y, Sullivan HL, Carrow K, Mesfin JM, Korpanty J, Worthington K, Luo C, Christman KL, Gianneschi NC. Inflammation-Responsive Micellar Nanoparticles from Degradable Polyphosphoramidates for Targeted Delivery to Myocardial Infarction. J Am Chem Soc 2023; 145:11185-11194. [PMID: 37184379 DOI: 10.1021/jacs.3c01054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Nanoparticles that undergo a localized morphology change to target areas of inflammation have been previously developed but are limited by their lack of biodegradability. In this paper, we describe a low-ring-strain cyclic olefin monomer, 1,3-dimethyl-2-phenoxy-1,3,4,7-tetrahydro-1,3,2-diazaphosphepine 2-oxide (MePTDO), that rapidly polymerizes via ring-opening metathesis polymerization at room temperature to generate well-defined degradable polyphosphoramidates with high monomer conversion (>84%). Efficient MePTDO copolymerizations with norbornene-based monomers are demonstrated, including a norbornenyl monomer functionalized with a peptide substrate for inflammation-associated matrix metalloproteinases (MMPs). The resulting amphiphilic peptide brush copolymers self-assembled in aqueous solution to generate micellar nanoparticles (30 nm in diameter) which exhibit excellent cyto- and hemocompatibility and undergo MMP-induced assembly into micron-scale aggregates. As MMPs are upregulated in the heart postmyocardial infarction (MI), the MMP-responsive micelles were applied to target and accumulate in the infarcted heart following intravenous administration in a rat model of MI. These particles displayed a distinct biodistribution and clearance pattern in comparison to nondegradable analogues. Specifically, accumulation at the site of MI competed with elimination predominantly through the kidney rather than the liver. Together, these results suggest this as a promising new biodegradable platform for inflammation targeted delivery.
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Affiliation(s)
- Yifei Liang
- Department of Chemistry, International Institute for Nanotechnology, Simpson-Querrey Institute, Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
| | - Holly L Sullivan
- Shu Chien-Gene Lay Department of Bioengineering and the Sanford Consortium for Regenerative Medicine, University of California San Diego, La Jolla, California 92037, United States
| | - Kendal Carrow
- Medical Scientist Training Program, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611, United States
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Joshua M Mesfin
- Shu Chien-Gene Lay Department of Bioengineering and the Sanford Consortium for Regenerative Medicine, University of California San Diego, La Jolla, California 92037, United States
| | - Joanna Korpanty
- Department of Chemistry, International Institute for Nanotechnology, Simpson-Querrey Institute, Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
| | - Kendra Worthington
- Shu Chien-Gene Lay Department of Bioengineering and the Sanford Consortium for Regenerative Medicine, University of California San Diego, La Jolla, California 92037, United States
| | - Colin Luo
- Shu Chien-Gene Lay Department of Bioengineering and the Sanford Consortium for Regenerative Medicine, University of California San Diego, La Jolla, California 92037, United States
| | - Karen L Christman
- Shu Chien-Gene Lay Department of Bioengineering and the Sanford Consortium for Regenerative Medicine, University of California San Diego, La Jolla, California 92037, United States
| | - Nathan C Gianneschi
- Department of Chemistry, International Institute for Nanotechnology, Simpson-Querrey Institute, Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Department of Materials Science & Engineering, Department of Pharmacology, Northwestern University, Evanston, Illinois 60208, United States
- Department of Chemistry & Biochemistry, University of California San Diego, La Jolla, California 92037, United States
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