1
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Ham JS, Son M, Na CG, Park B, Baik MH, Sarpong R. Construction of Seven-Membered Oxacycles Using a Rh(I)-Catalyzed Cascade C-C Formation/Cleavage of Cyclobutenol Derivatives. J Org Chem 2024; 89:4647-4656. [PMID: 38497619 DOI: 10.1021/acs.joc.3c02914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Herein, we describe the synthesis of substituted oxepane derivatives through the skeletal remodeling of 4-hydroxy-2-cyclobutenones, which are readily prepared from commercially available dialkyl squarates upon their reaction with acrylonitrile. Mechanistically, a Rh(I)-catalyzed C-C bond formation and cleavage cascade is proposed. Specifically, a fused [3.2.0] bicycle is proposed to form from dialkyl squarate-derived cyclobutenols via an unusual Rh(I)-catalyzed intermolecular oxa-Michael addition of a tertiary alcohol with acrylonitrile, followed by an intramolecular conjugate addition/migratory insertion. Subsequent C(sp3)-C(sp3) bond cleavage through a Rh-catalyzed β-carbon elimination is then theorized to furnish the oxepane scaffold. Computational studies support the formation of an intermediate [3.2.0] bicycle but also point to an alternative pathway for the formation of the oxepane products involving a Rh(III) intermediate. Additional studies have shown the overall process to be stereoretentive. The functional groups that are introduced in this process can be leveraged to form fused or bridged ring systems.
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Affiliation(s)
- Jin Su Ham
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Mina Son
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea
| | - Christina G Na
- Department of Chemistry, University of California, Berkeley, California 94720, United States
| | - Bohyun Park
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea
| | - Mu-Hyun Baik
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea
| | - Richmond Sarpong
- Department of Chemistry, University of California, Berkeley, California 94720, United States
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2
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Tsuda T, Sheng M, Ishikawa H, Yamazoe S, Yamasaki J, Hirayama M, Yamaguchi S, Mizugaki T, Mitsudome T. Iron phosphide nanocrystals as an air-stable heterogeneous catalyst for liquid-phase nitrile hydrogenation. Nat Commun 2023; 14:5959. [PMID: 37770434 PMCID: PMC10539298 DOI: 10.1038/s41467-023-41627-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 09/12/2023] [Indexed: 09/30/2023] Open
Abstract
Iron-based heterogeneous catalysts are ideal metal catalysts owing to their abundance and low-toxicity. However, conventional iron nanoparticle catalysts exhibit extremely low activity in liquid-phase reactions and lack air stability. Previous attempts to encapsulate iron nanoparticles in shell materials toward air stability improvement were offset by the low activity of the iron nanoparticles. To overcome the trade-off between activity and stability in conventional iron nanoparticle catalysts, we developed air-stable iron phosphide nanocrystal catalysts. The iron phosphide nanocrystal exhibits high activity for liquid-phase nitrile hydrogenation, whereas the conventional iron nanoparticles demonstrate no activity. Furthermore, the air stability of the iron phosphide nanocrystal allows facile immobilization on appropriate supports, wherein TiO2 enhances the activity. The resulting TiO2-supported iron phosphide nanocrystal successfully converts various nitriles to primary amines and demonstrates high reusability. The development of air-stable and active iron phosphide nanocrystal catalysts significantly expands the application scope of iron catalysts.
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Affiliation(s)
- Tomohiro Tsuda
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
| | - Min Sheng
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
| | - Hiroya Ishikawa
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
| | - Seiji Yamazoe
- Department of Chemistry, Tokyo Metropolitan University, 1-1 Minami Osawa, Hachioji, Tokyo, 192-0397, Japan
| | - Jun Yamasaki
- Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, 7-1 Mihogaoka, Ibaraki, Osaka, 567-0047, Japan
| | - Motoaki Hirayama
- Department of Applied Physics, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
- RIKEN Center for Emergent Matter Science (CEMS), 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
- PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama, 333-0012, Japan
| | - Sho Yamaguchi
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
| | - Tomoo Mizugaki
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
- Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka, 565-0871, Japan
| | - Takato Mitsudome
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan.
- PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama, 333-0012, Japan.
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3
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Das P, Devi N, Gaur N, Goswami S, Dutta D, Dubey R, Puzari A. Acrylonitrile adducts: design, synthesis and biological evaluation as antimicrobial, haemolytic and thrombolytic agent. Sci Rep 2023; 13:6209. [PMID: 37069316 PMCID: PMC10110592 DOI: 10.1038/s41598-023-33605-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 04/15/2023] [Indexed: 04/19/2023] Open
Abstract
In this work, five acrylonitrile adducts were screened for antibacterial activity against Gram-positive Bacillus subtilis, Microbial Type Culture Collection and Gene Bank (MTCC 1305) and Gram-negative Escherichia coli (MTCC 443). Synthesis was followed by aza-Michael addition reaction, where the acrylonitrile accepts an electron pair from the respective amines and results in the formation of n-alkyliminobis-propionitrile and n-alkyliminopropionitrile under microwave irradiation. Characterization of the compounds were performed using Fourier Transform Infrared (FTIR), Proton Nuclear Magnetic Resonance (1H NMR) and Electrospray Ionisation Mass Spectrometry (ESI-MS). The particle size characterization was done by Dynamic Light Scattering (DLS) technique. The antibacterial study showed higher inhibition rate for both Gram-positive and Gram-negative bacteria. The antibacterial ability was found to be dose dependent. The minimum inhibitory concentration against both bacteria were found to be 1, 3, 0.4, 1, 3 µl/ml for E. coli and 6, 6, 0.9, 0.5, 5 µl/ml for B. subtilis. Time-kill kinetics evaluation showed that the adducts possess bacteriostatic action. Further it was evaluated for high-throughput in vitro assays to determine the compatibility of the adducts for drug delivery. The haemolytic and thrombolytic activity was analysed against normal mouse erythrocytes. The haemolytic activity showed prominent results, and thereby projecting this acrylonitrile adducts as potent antimicrobial and haemolytic agent.
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Affiliation(s)
- Parineeta Das
- Department of Chemistry, National Institute of Technology Nagaland, Chumoukedima, Nagaland, 797103, India
| | - Nirmala Devi
- Chulalongkorn University, Bangkok, 10330, Thailand
| | - Nisha Gaur
- Defence Research Laboratory, Post Bag No. 2, Tezpur, Assam, 784001, India
| | - Swagata Goswami
- Defence Research Laboratory, Post Bag No. 2, Tezpur, Assam, 784001, India
| | - Dhiraj Dutta
- Defence Research Laboratory, Post Bag No. 2, Tezpur, Assam, 784001, India
| | - Rama Dubey
- Defence Research Laboratory, Post Bag No. 2, Tezpur, Assam, 784001, India
| | - Amrit Puzari
- Department of Chemistry, National Institute of Technology Nagaland, Chumoukedima, Nagaland, 797103, India.
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4
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Ratzenböck K, Fischer SM, Slugovc C. Poly(ether)s derived from oxa-Michael polymerization: a comprehensive review. MONATSHEFTE FUR CHEMIE 2023. [DOI: 10.1007/s00706-023-03049-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
AbstractPoly(ether)s represent an important class of polymers and are typically formed by ring-opening polymerization, Williamson ether synthesis, or self-condensation of alcohols. The oxa-Michael reaction presents another method to form poly(ether)s with additional functional groups in the polymer backbone starting from di- or triols and electron deficient olefins such as acrylates, sulfones, or acrylamides. However, research on oxa-Michael polymerization is still limited. Herein, we outline the principles of the oxa-Michael polymerization and focus on the synthesis and preparation of poly(ether-sulfone)s, poly(ether-ester)s, poly(ether)s, and poly(ether-amide)s. Further, challenges as well as future perspectives of the oxa-Michael polymerization are discussed.
Graphical abstract
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5
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Chen BL, Jing S, Zhu XQ. Thermodynamics Evaluation of Selective Hydride Reduction for α,β-Unsaturated Carbonyl Compounds. Molecules 2023; 28:molecules28062862. [PMID: 36985834 PMCID: PMC10051270 DOI: 10.3390/molecules28062862] [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: 02/20/2023] [Revised: 03/14/2023] [Accepted: 03/17/2023] [Indexed: 03/30/2023] Open
Abstract
The selective reduction of α,β-unsaturated carbonyl compounds is one of the core reactions and also a difficult task for organic synthesis. We have been attempting to study the thermodynamic data of these compounds to create a theoretical basis for organic synthesis and computational chemistry. By electrochemical measurement method and titration calorimetry, in acetonitrile at 298 K, the hydride affinity of two types of unsaturated bonds in α,β-unsaturated carbonyl compounds, their single-electron reduction potential, and the single-electron reduction potential of the corresponding radical intermediate are determined. Their hydrogen atom affinity, along with the hydrogen atom affinity and proton affinity of the corresponding radical anion, is also derived separately based on thermodynamic cycles. The above data are used to establish the corresponding "Molecule ID Card" (Molecule identity card) and analyze the reduction mechanism of unsaturated carbonyl compounds. Primarily, the mixture of any carbonyl hydride ions and Ac-tempo+ will stimulate hydride transfer process and create corresponding α,β-unsaturated carbonyl compounds and Ac-tempoH from a thermodynamic point of view.
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Affiliation(s)
- Bao-Long Chen
- The State Key Laboratory of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Sha Jing
- The State Key Laboratory of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xiao-Qing Zhu
- The State Key Laboratory of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering, College of Chemistry, Nankai University, Tianjin 300071, China
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6
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Thia-Michael Reaction under Heterogeneous Catalysis. ORGANICS 2023. [DOI: 10.3390/org4010007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023] Open
Abstract
Thia-Michael reactions between aliphatic and aromatic thiols and various Michael acceptors were performed under environmentally-friendly solvent-free conditions using Amberlyst® A21 as a recyclable heterogeneous catalyst to efficiently obtain the corresponding adducts in high yields. Ethyl acrylate was the main acceptor used, although others such as acrylamide, linear, and cyclic enones were also utilized successfully. Bifunctional Michael donor, 3-mercaptopropanoic acid, positively furnished the product, albeit in a lower yield and after leaving the reaction to take place for a longer time. The catalyst was easy and safe to handle and successfully recycled for five consecutive cycles.
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7
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Luo C, Alegre-Requena JV, Sujansky SJ, Pajk SP, Gallegos LC, Paton RS, Bandar JS. Mechanistic Studies Yield Improved Protocols for Base-Catalyzed Anti-Markovnikov Alcohol Addition Reactions. J Am Chem Soc 2022; 144:9586-9596. [PMID: 35605253 DOI: 10.1021/jacs.1c13397] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The catalytic anti-Markovnikov addition of alcohols to simple alkenes is a longstanding synthetic challenge. We recently disclosed the use of organic superbase catalysis for the nucleophilic addition of alcohols to activated styrene derivatives. This article describes mechanistic studies on this reversible reaction, including thermodynamic and kinetic profiling as well as computational modeling. Our findings show the negative entropy of addition is counterbalanced by an enthalpy that is most favored in nonpolar solvents. However, a large negative alcohol rate order under these conditions indicates excess alcohol sequesters the active alkoxide ion pairs, slowing the reaction rate. These observations led to an unexpected solution to a thermodynamically challenging reaction: use of less alcohol enables faster addition, which in turn allows for lower reaction temperatures to counteract Le Chatelier's principle. Thus, our original method has been improved with new protocols that do not require excess alcohol stoichiometry, enable an expanded alkene substrate scope, and allow for the use of more practical catalyst systems. The generality of this insight for other challenging hydroetherification reactions is also demonstrated through new alkenol cyclization and oxa-Michael addition reactions.
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Affiliation(s)
- Chaosheng Luo
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Juan V Alegre-Requena
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Stephen J Sujansky
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Spencer P Pajk
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Liliana C Gallegos
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Robert S Paton
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Jeffrey S Bandar
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
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8
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Das P, Devi N, Puzari A. One-pot solvent-free microwave-assisted aza-Michael addition reaction of acrylonitrile. J INDIAN CHEM SOC 2022. [DOI: 10.1016/j.jics.2022.100411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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9
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Pramanik M, Mathuri A, Mal P. t BuOLi-promoted terminal alkyne functionalizations by aliphatic thiols and alcohols. Org Biomol Chem 2022; 20:2671-2680. [PMID: 35293412 DOI: 10.1039/d2ob00079b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Selective radical addition to terminal alkynes is always a difficult task to achieve because it gives a mixture of stereo- and regioisomers. Herein we describe the selective addition of aliphatic thiols or alcohols to N-phenylpropiolamides (terminal alkynes) using lithium tert-butoxide (tBuOLi) in ethanol as a promoter. Mechanistically, it has been shown that the reaction proceeded through the generation of a thiyl radical intermediate, and the amide group in N-phenylpropiolamide could help in the activation of the alkyne, which led to thioacetalization via the formation of a (Z)-selective anti-Markovnikov vinyl sulfide. The (Z)-selectivity during the formation of vinyl sulfides was controlled by an intramolecular sulfur⋯oxygen interaction.
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Affiliation(s)
- Milan Pramanik
- School of Chemical Sciences, National Institute of Science Education and Research (NISER) Bhubaneswar, An OCC of Homi Bhabha National Institute, PO Bhimpur-Padanpur, Via Jatni, District Khurda, Odisha 752050, India.
| | - Ashis Mathuri
- School of Chemical Sciences, National Institute of Science Education and Research (NISER) Bhubaneswar, An OCC of Homi Bhabha National Institute, PO Bhimpur-Padanpur, Via Jatni, District Khurda, Odisha 752050, India.
| | - Prasenjit Mal
- School of Chemical Sciences, National Institute of Science Education and Research (NISER) Bhubaneswar, An OCC of Homi Bhabha National Institute, PO Bhimpur-Padanpur, Via Jatni, District Khurda, Odisha 752050, India.
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10
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Thiyagarajan S, Sankar RV, Anjalikrishna PK, Suresh CH, Gunanathan C. Catalytic Formal Conjugate Addition: Direct Synthesis of δ-Hydroxynitriles from Nitriles and Allylic Alcohols. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05271] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Subramanian Thiyagarajan
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), HBNI, Bhubaneswar 752050, India
| | - Raman Vijaya Sankar
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), HBNI, Bhubaneswar 752050, India
| | - Puthannur K. Anjalikrishna
- Chemical Sciences and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Cherumuttathu H. Suresh
- Chemical Sciences and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Chidambaram Gunanathan
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), HBNI, Bhubaneswar 752050, India
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11
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Yoon S, Lee S, Nam SH, Lee H, Lee Y. Synthesis of N-substituted quaternary carbon centers through KO t-Bu-catalyzed aza-Michael addition of pyrazoles to cyclic enones. Org Biomol Chem 2022; 20:8313-8322. [DOI: 10.1039/d2ob01634f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This study reports an effective and mild protocol for the construction of N-substituted quaternary carbon centers via the KOt-Bu-catalyzed aza-Michael addition of pyrazoles with β-substituted cyclic enones.
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Affiliation(s)
- Subin Yoon
- Department of Chemistry, Kwangwoon University, Seoul 01897, Republic of Korea
| | - Sungbin Lee
- Department of Chemistry, Kwangwoon University, Seoul 01897, Republic of Korea
| | - Seung Hyun Nam
- Department of Chemistry, Kwangwoon University, Seoul 01897, Republic of Korea
| | - Hyejeong Lee
- College of Pharmacy, Duksung Women's University, Seoul 01369, Republic of Korea
| | - Yunmi Lee
- Department of Chemistry, Kwangwoon University, Seoul 01897, Republic of Korea
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12
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Tanemura K. Large acceleration under highly concentrated conditions: Synthesis of chalcones using a small amount of DMF or [emim]N(CN)2. RESULTS IN CHEMISTRY 2022. [DOI: 10.1016/j.rechem.2022.100316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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13
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Fischer SM, Kaschnitz P, Slugovc C. Tris(2,4,6-trimethoxyphenyl)phosphine – a Lewis base able to compete with phosphazene bases in catalysing oxa-Michael reactions. Catal Sci Technol 2022. [DOI: 10.1039/d2cy01335e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The performance of the fairly airstable and commercially available “Lewis base beast” TTMPP in catalysing oxa-Michael reactions and the control of its activity by dilution and solvent choice are disclosed.
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Affiliation(s)
- Susanne M. Fischer
- Christian Doppler Laboratory for Organocatalysis in Polymerization, Stremayrgasse 9, 8010 Graz, Austria
- Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
| | - Petra Kaschnitz
- Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
| | - Christian Slugovc
- Christian Doppler Laboratory for Organocatalysis in Polymerization, Stremayrgasse 9, 8010 Graz, Austria
- Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
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14
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Tanemura K. Reduction of aldehydes and ketones by a stoichiometric amount of NaBH4 using a small amount of MeOH or EtOH. RESULTS IN CHEMISTRY 2022. [DOI: 10.1016/j.rechem.2022.100486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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15
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Tanemura K. Acceleration under solvent-drop grinding: Synthesis of bis(indolyl)methanes using small amounts of organic solvents or ionic liquids. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.153391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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16
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Shigeno M, Shishido Y, Hayashi K, Nozawa‐Kumada K, Kondo Y. KO‐
t
‐Bu Catalyzed Thiolation of
β
‐(Hetero)arylethyl Ethers via MeOH Elimination/hydrothiolation. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100597] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Masanori Shigeno
- Department of Biophysical Chemistry Graduate School of Pharmaceutical Science Tohoku University 6–3 Aoba Sendai 980-8578 Japan
| | - Yoshiteru Shishido
- Department of Biophysical Chemistry Graduate School of Pharmaceutical Science Tohoku University 6–3 Aoba Sendai 980-8578 Japan
| | - Kazutoshi Hayashi
- Department of Biophysical Chemistry Graduate School of Pharmaceutical Science Tohoku University 6–3 Aoba Sendai 980-8578 Japan
| | - Kanako Nozawa‐Kumada
- Department of Biophysical Chemistry Graduate School of Pharmaceutical Science Tohoku University 6–3 Aoba Sendai 980-8578 Japan
| | - Yoshinori Kondo
- Department of Biophysical Chemistry Graduate School of Pharmaceutical Science Tohoku University 6–3 Aoba Sendai 980-8578 Japan
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17
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Fischer SM, Renner S, Boese AD, Slugovc C. Electron-rich triarylphosphines as nucleophilic catalysts for oxa-Michael reactions. Beilstein J Org Chem 2021; 17:1689-1697. [PMID: 34367347 PMCID: PMC8313974 DOI: 10.3762/bjoc.17.117] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 07/07/2021] [Indexed: 11/29/2022] Open
Abstract
Electron-rich triarylphosphines, namely 4-(methoxyphenyl)diphenylphosphine (MMTPP) and tris(4-trimethoxyphenyl)phosphine (TMTPP), outperform commonly used triphenylphosphine (TPP) in catalyzing oxa-Michael additions. A matrix consisting of three differently strong Michael acceptors and four alcohols of varying acidity was used to assess the activity of the three catalysts. All test reactions were performed with 1 mol % catalyst loading, under solvent-free conditions and at room temperature. The results reveal a decisive superiority of TMTPP for converting poor and intermediate Michael acceptors such as acrylamide and acrylonitrile and for converting less acidic alcohols like isopropanol. With stronger Michael acceptors and more acidic alcohols, the impact of the more electron-rich catalysts is less pronounced. The experimental activity trend was rationalized by calculating the Michael acceptor affinities of all phosphine-Michael acceptor combinations. Besides this parameter, the acidity of the alcohol has a strong impact on the reaction speed. The oxidation stability of the phosphines was also evaluated and the most electron-rich TMTPP was found to be only slightly more sensitive to oxidation than TPP. Finally, the catalysts were employed in the oxa-Michael polymerization of 2-hydroxyethyl acrylate. With TMTPP polymers characterized by number average molar masses of about 1200 g/mol at room temperature are accessible. Polymerizations carried out at 80 °C resulted in macromolecules containing a considerable share of Rauhut-Currier-type repeat units and consequently lower molar masses were obtained.
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Affiliation(s)
- Susanne M Fischer
- Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
- Christian Doppler Laboratory for Organocatalysis in Polymerization, Stremayrgasse 9, 8010 Graz, Austria
| | - Simon Renner
- Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
| | - A Daniel Boese
- Physical and Theoretical Chemistry, Institute of Chemistry, University of Graz, Heinrichstrasse 28/IV, 8010 Graz, Austria
| | - Christian Slugovc
- Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
- Christian Doppler Laboratory for Organocatalysis in Polymerization, Stremayrgasse 9, 8010 Graz, Austria
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18
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Ahmad T, Ullah N. The oxa-Michael reaction in the synthesis of 5- and 6-membered oxygen-containing heterocycles. Org Chem Front 2021. [DOI: 10.1039/d0qo01312a] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
In this review, we provide an updated account on the recent advances and applications of oxa-Michael reaction in the synthesis 5- and 6-membered monocyclic oxygen-containing heterocyclic compounds published in the literature since 2013 to date.
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Affiliation(s)
- Tauqir Ahmad
- Chemistry Department
- King Fahd University of Petroleum and Minerals
- Dhahran 31261
- Saudi Arabia
| | - Nisar Ullah
- Chemistry Department
- King Fahd University of Petroleum and Minerals
- Dhahran 31261
- Saudi Arabia
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19
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Kim K, Park S, Lee Y. KO
t
‐Bu‐Catalyzed Chemo‐ and Regioselective Hydroamination of Allylic Sulfones with Indoles. European J Org Chem 2020. [DOI: 10.1002/ejoc.202001394] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Kundo Kim
- Department of Chemistry Kwangwoon University Seoul 01897, Republic of Korea
| | - Subin Park
- Department of Chemistry Kwangwoon University Seoul 01897, Republic of Korea
| | - Yunmi Lee
- Department of Chemistry Kwangwoon University Seoul 01897, Republic of Korea
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Madasu J, Shinde S, Das R, Patel S, Shard A. Potassium tert-butoxide mediated C-C, C-N, C-O and C-S bond forming reactions. Org Biomol Chem 2020; 18:8346-8365. [PMID: 33020791 DOI: 10.1039/d0ob01382j] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Potassium tertiary butoxide (KOtBu) mediated constructions of C-C, C-O, C-N, and C-S bonds are reviewed with special emphasis on their synthetic applications. KOtBu can be used to perform reactions already known to be carried out using transition metals, but it has advantages in terms of environmental congruence and economic cost. KOtBu is widely employed in organic synthesis to mediate the construction of C-C, C-O, C-N, C-S and miscellaneous bonds in good to excellent yields. Synthetic uses of KOtBu in coupling, alkylation, arylation, α-phenylation, cyclization, Heck-type, annulation, photo-arylation, aromatic-substitution, amidation, and silylation reactions are summarized and discussed. The mechanisms through which KOtBu carries out a specific reaction are also discussed. One of the goals of this review is to attract the attention of chemists as to the benefits of using KOtBu as an environmentally benign alternative to transition metals and its applications in the construction of chemical bonds with predominant importance in organic synthesis. This review completely covers the synthetic protocols that have been performed using KOtBu in the last two decades.
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Affiliation(s)
- Jayashree Madasu
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gujarat 380054, India.
| | - Shital Shinde
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gujarat 380054, India.
| | - Rudradip Das
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gujarat 380054, India.
| | - Sagarkumar Patel
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gujarat 380054, India.
| | - Amit Shard
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, Gujarat 380054, India.
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Zhang XW, Zhang H, Wang HC, Zhu MH, Cong H, Liu WB. Pd-catalyzed arylation/aza-Michael addition cascade to C2-spiroindolines and azabicyclo[3.2.2]nonanones. Chem Commun (Camb) 2020; 56:12013-12016. [PMID: 32901620 DOI: 10.1039/d0cc04935b] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
A palladium-catalyzed arylation/aza-Michael addition cascade reaction of β-substituted cyclic enones and 2-haloanilines has been reported. Using 1 mol% Pd(PPh3)4 as a catalyst, C2-spiroindolines are accessed via an intermolecular vinylogous arylation of β-alkyl cyclic enones and 2-haloanilines followed by an intramolecular aza-Michael addition. The functional group tolerance of this transformation is examined by 18 examples in up to 93% yield. In the second part, we developed an α'-arylation/aza-Michael addition cascade strategy to construct azabicyclo[3.2.2]nonanones catalyzed by Pd(MeCN)2Cl2·PPh3. This study provides a quick route to complex and useful spiro- and bridged-heterocycles from readily available starting materials in good yields with high regioselectivity.
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Affiliation(s)
- Xiao-Wen Zhang
- Sauvage Center for Molecular Sciences, Engineering Research Center of Organosilicon Compounds & Materials (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Hubei 430072, China.
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