1
|
Chen J, Wei WT, Li Z, Lu Z. Metal-catalyzed Markovnikov-type selective hydrofunctionalization of terminal alkynes. Chem Soc Rev 2024; 53:7566-7589. [PMID: 38904176 DOI: 10.1039/d4cs00167b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
Metal-catalyzed highly Markovnikov-type selective hydrofunctionalization of terminal alkynes provides a straightforward and atom-economical route to access 1,1-disubstituted alkenes, which have a wide range of applications in organic synthesis. However, the highly Markovnikov-type selective transformations are challenging due to the electronic and steric effects during the addition process. With the development of metal-catalyzed organic synthesis, different metal catalysts have been developed to solve this challenge, especially for platinum group metal catalysts. In this perspective, we review homogeneous metal-catalyzed Markovnikov-type selective hydrofunctionalization of terminal alkynes according to the classified element types as well as reaction mechanisms. Future avenues for investigation are also presented to help expand this exciting field.
Collapse
Affiliation(s)
- Jieping Chen
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310058, China.
| | - Wen-Ting Wei
- School of Materials Science and Chemical Engineering, Ningbo University, Zhejiang, 315211, China
| | - Zhuocheng Li
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310058, China.
| | - Zhan Lu
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310058, China.
| |
Collapse
|
2
|
Centeno-Vega I, Megías-Sayago C, Ivanova S. New insights for valorization of polyolefins/light alkanes: catalytic dehydrogenation of n-alkanes by immobilized pincer-iridium complexes. Dalton Trans 2024; 53:11216-11227. [PMID: 38887859 DOI: 10.1039/d4dt00847b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
This scientific review delves into the innovative realm of polyolefins/light alkanes valorization through their catalytic dehydrogenation employing pincer-ligated iridium organometallic complexes. These widely studied catalysts exhibit outstanding properties, although the intrinsic characteristics of homogeneous catalysis (such as challenging product-catalyst separation, poor applicability to continuous-flow processes and low recyclability) limit their activity and industrial application, as well as their thermal stability. Through the immobilization of complexes on inorganic supports, these downsides have been bypassed, harnessing the true potential of these catalysts, affording more selective and stable catalysts in addition to facilitating their implementation in industrial processes. The findings described herein contribute to the advancement in the understanding of catalytic processes in hydrocarbon transformations, offering promising avenues for sustainable and selective production of valuable chemical intermediates from readily available feedstocks.
Collapse
Affiliation(s)
- Ignacio Centeno-Vega
- Departamento de Química Inorgánica, Instituto de Investigaciones Químicas and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Centro Mixto CSIC-Universidad de Sevilla, 41092 Sevilla, Spain.
| | - Cristina Megías-Sayago
- Departamento de Química Inorgánica, Instituto de Investigaciones Químicas and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Centro Mixto CSIC-Universidad de Sevilla, 41092 Sevilla, Spain.
| | - Svetlana Ivanova
- Departamento de Química Inorgánica e Instituto de Ciencia de Materiales de Sevilla, Centro Mixto CSIC-Universidad de Sevilla, 41092 Sevilla, Spain
| |
Collapse
|
3
|
Li H, Zhang B, Feng R, Guo S. An N-heterocyclic carbene-based pincer system of palladium and its versatile reactivity under oxidizing conditions. Dalton Trans 2024; 53:11470-11480. [PMID: 38912609 DOI: 10.1039/d4dt00980k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/25/2024]
Abstract
NHC-based pincers (NHC = N-heterocyclic carbene) have been broadly employed as supporting platforms, and their palladium complexes have found many synthetic applications. However, previous studies mainly focused on the NHC pincers of palladium featuring an oxidation number of +II. In contrast, oxidation of these well-defined Pd(II) species and the study of their fundamental high-valent Pd chemistry remain largely undeveloped. In addition, from a perspective of PdII/PdIV catalysis, the reactivity and degradation of NHC pincers in catalytically relevant reactions have not been well understood. In this work, a series of Pd(II) complexes supported by a well-known NHC^Aryl^NHC pincer platform have been prepared. Their reactivity towards various oxidizing reagents, including halogen surrogates, electrophilic fluorine reagents, and alkyl/aryl halides, has been examined. In some cases, ambient-characterizable high-valent Pd NHCs, which have been scarcely reported, were obtained. The carbenes incorporated into the pincer framework proved to be effective spectator donors. In contrast, the central aryl moiety exhibits versatile reactivity and collapse pathways, allowing it to function either as a spectator or a non-innocent actor.
Collapse
Affiliation(s)
- Haobin Li
- Department of Chemistry, Capital Normal University, Beijing 100048, China.
| | - Bo Zhang
- Department of Chemistry, Capital Normal University, Beijing 100048, China.
| | - Rui Feng
- Department of Chemistry, Capital Normal University, Beijing 100048, China.
| | - Shuai Guo
- Department of Chemistry, Capital Normal University, Beijing 100048, China.
| |
Collapse
|
4
|
Predarska I, Körber W, Lönnecke P, Gelman D, Hey-Hawkins E. Synthesis and catalytic activity of heterobimetallic Au/M (M = Rh III, Ir III) complexes with ditopic mono- and triphosphane ligands. Dalton Trans 2024. [PMID: 38953230 DOI: 10.1039/d4dt01247j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/03/2024]
Abstract
A series of heterobimetallic complexes Au/M (M = RhIII, IrIII) were prepared on the basis of two ditopic ligands: a monophosphane ligand L1H and a triphosphane ligand L2H. The complexes were fully characterised, including single-crystal X-ray diffraction studies. Catalytic activity of cationic L1/AuI/IrIII and L2/AuI/IrIII bis(trifluoromethane)sulfonimide was analysed through their capacity to induce allenyl ether rearrangement and cycloisomerisation of N-propargyl benzamide. While cationic L1/AuI/IrIII showed some ability to induce allenyl ether rearrangement, no conversion was observed for cationic L2/AuI/IrIII. Similarly, N-propargyl benzamide could undergo cycloisomerisation in the presence of cationic L1/AuI/IrIII, whereas cationic L2/AuI/IrIII was again inactive. These findings highlight how crucial the surroundings of the metal centre are to the catalytic activity. Catalytic activity is only possible when Au has a free coordination site; the gold complex becomes inactive when the tridentate ligand is present.
Collapse
Affiliation(s)
- Ivana Predarska
- Leipzig University, Faculty of Chemistry and Mineralogy, Institute of Inorganic Chemistry, Johannisallee 29, 04103 Leipzig, Germany.
| | - Wieland Körber
- Leipzig University, Faculty of Chemistry and Mineralogy, Institute of Inorganic Chemistry, Johannisallee 29, 04103 Leipzig, Germany.
| | - Peter Lönnecke
- Leipzig University, Faculty of Chemistry and Mineralogy, Institute of Inorganic Chemistry, Johannisallee 29, 04103 Leipzig, Germany.
| | - Dmitri Gelman
- The Hebrew University, Institute of Chemistry, Edmond Safra Campus, 9190401 Jerusalem, Israel.
| | - Evamarie Hey-Hawkins
- Leipzig University, Faculty of Chemistry and Mineralogy, Institute of Inorganic Chemistry, Johannisallee 29, 04103 Leipzig, Germany.
| |
Collapse
|
5
|
Demchuk MJ, Zurakowski JA, Drover MW. Tridentate κ 3- P, P, C iridium complexes: influence of ligand saturation on intramolecular C-H bond activation. Chem Commun (Camb) 2024. [PMID: 38888889 DOI: 10.1039/d4cc01435a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
Whereas κ3-P,C,P-based donor ligands are ubiquitous across synthetic chemistry, related unsymmetric systems having κ3-P,P,C-coordination are comparatively rare. In this contribution, we expose a new κ3-P,P,C ligand system, bearing a C3-anionic linker and its coordination chemistry with iridium. The title ligand has been coordinated in saturated and unsaturated forms. The degree of ligand saturation affected an onward (and unusual) oxidative rearrangement reaction.
Collapse
Affiliation(s)
- Mitchell J Demchuk
- Department of Chemistry, Western University, 1151 Richmond Street, London, ON, N8K 3G6, Canada.
| | - Joseph A Zurakowski
- Department of Chemistry, Western University, 1151 Richmond Street, London, ON, N8K 3G6, Canada.
- Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Avenue, ON, N9B 3P4, Canada
| | - Marcus W Drover
- Department of Chemistry, Western University, 1151 Richmond Street, London, ON, N8K 3G6, Canada.
| |
Collapse
|
6
|
Neshat A, Mousavizadeh Mobarakeh A, Yousefshahi MR, Varmaghani F, Dusek M, Eigner V, Kucerakova M. Introducing Novel Redox-Active Bis(phenolate) N-Heterocyclic Carbene Proligands: Investigation of Their Coordination to Fe(II)/Fe(III) and Their Catalytic Activity in Transfer Hydrogenation of Carbonyl Compounds. ACS OMEGA 2024; 9:25135-25145. [PMID: 38882110 PMCID: PMC11170717 DOI: 10.1021/acsomega.4c02602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 05/19/2024] [Accepted: 05/23/2024] [Indexed: 06/18/2024]
Abstract
A simple and efficient procedure for synthesizing novel pincer-type tridentate N-heterocyclic carbene bisphenolate ligands is reported. The synthesis of pincer proligands with N,N'-disubstituted imidazoline core, 5 and 6, was carried out via triethylorthoformate-promoted cyclization of either N,N'-bis(2-hydroxy-3,5-di-tert-butylphenyl)cyclohexanediamine, 3, or N,N'-bis(2-hydroxyphenyl)cyclohexanediamine, 4, in the presence of concentrated hydrochloric acid. Cyclic voltammograms of the ligands revealed ligand-centered redox activity, indicating the noninnocent nature of the ligands. The voltammograms of the ligands exhibit two successive one-electron oxidations and two consecutive one-electron reductions. In contrast to previous reports, the redox-active ligands in this study exhibit one-electron oxidation and reduction processes. All products were thoroughly characterized by using 1H and 13C NMR spectroscopy. The base-promoted deprotonation of the proligands and subsequent reaction with iron(II) and iron(III) chlorides yielded compounds 7 and 8. These compounds are binuclear and tetranuclear iron(III) complexes that do not contain carbene functional groups. Complexes 7 and 8 were characterized by using elemental analysis and single-crystal X-ray crystallography. At low catalyst loadings, both 7 and 8 exhibited high catalytic activity in the transfer hydrogenation of selected aldehydes and ketones.
Collapse
Affiliation(s)
- Abdollah Neshat
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), 444 Prof. Sobouti Blvd., Gava Zang, Zanjan 45137-66731, Iran
| | - Ali Mousavizadeh Mobarakeh
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), 444 Prof. Sobouti Blvd., Gava Zang, Zanjan 45137-66731, Iran
| | - Mohammad Reza Yousefshahi
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), 444 Prof. Sobouti Blvd., Gava Zang, Zanjan 45137-66731, Iran
| | - Fahimeh Varmaghani
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), 444 Prof. Sobouti Blvd., Gava Zang, Zanjan 45137-66731, Iran
| | - Michal Dusek
- Institute of Physics of the Czech Academy of Sciences, Na Slovance 2, 18221 Prague 8, The Czech Republic
| | - Vaclav Eigner
- Institute of Physics of the Czech Academy of Sciences, Na Slovance 2, 18221 Prague 8, The Czech Republic
| | - Monika Kucerakova
- Institute of Physics of the Czech Academy of Sciences, Na Slovance 2, 18221 Prague 8, The Czech Republic
| |
Collapse
|
7
|
Mast M, Schubert H, Mayer HA, Wesemann L. Trianionic Carbocyclic NCN Pincer Ligand: Coordination Chemistry and Reactivity Studies. Inorg Chem 2024; 63:10860-10870. [PMID: 38804041 DOI: 10.1021/acs.inorgchem.4c01602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
(BCHT-NCN)H3 (1) [1,6-bis(methylene(bis-2,6-diisopropylaniline)(benzo)cycloheptatriene)] was synthesized by nucleophilic substitution treating 1,6-bis(methylenebromide)(benzo)cycloheptatriene with 2 equiv of Li[2,6-iPr2C6H3NH], Li[Dipp-NH]. Triple deprotonation of (BCHT-NCN)H3 (1) using n-BuLi yields the deprotonation product [(BCHT-NCN)Li3] (2), which crystallizes as a dimer [{[BCHT-NCN]Li3(Et2O)2}2] (2)2. Coordination compounds of the trianionic pincer ligand were obtained with SnCl2, YCl3(THF)3.5, and HfCl4(THF)2: [(BCHT-NCN)SnLi] (3), [(BCHT-NCN)Y(THF)2] (4), [(BCHT-NCN)HfCl2][Li(THF)4] (5), respectively. A hafnium hydride complex [(BCHT-NCN)HfH(HBEt3)][K(Et2O)2] (6) was isolated after reaction of 5 with K[HBEt3]. A MeNHC substitution product [(BCHT-NCN)HfCl(MeNHC)] (7) was synthesized treating compound 5 with MeNHC at rt. Following an n-BuLi reaction of 7 gives an alkyl complex [(BCHT-NCN)Hf(n-Bu)(MeNHC)] (8). Thermolysis of 7 yields the isomerization product [(BCHT-NCN#)HfCl(MeNHC)] (9), which was transferred into a methyl complex [(BCHT-NCN#)HfMe(MeNHC)] (10) upon treatment with MeMgBr. Hydride abstraction from complex 9 leads to a cationic complex [(BCHT-NCN+)HfCl(MeNHC)][Al(OtBuF)4] (11).
Collapse
Affiliation(s)
- Maximilian Mast
- Institut für Anorganische Chemie, Eberhard Karls Universität, Tübingen, Auf der Morgenstelle 18, Tübingen 72076, Germany
| | - Hartmut Schubert
- Institut für Anorganische Chemie, Eberhard Karls Universität, Tübingen, Auf der Morgenstelle 18, Tübingen 72076, Germany
| | - Hermann A Mayer
- Institut für Anorganische Chemie, Eberhard Karls Universität, Tübingen, Auf der Morgenstelle 18, Tübingen 72076, Germany
| | - Lars Wesemann
- Institut für Anorganische Chemie, Eberhard Karls Universität, Tübingen, Auf der Morgenstelle 18, Tübingen 72076, Germany
| |
Collapse
|
8
|
Huang FR, Yao QJ, Zhang P, Teng MY, Chen JH, Jiang LC, Shi BF. Cobalt-Catalyzed Domino Transformations via Enantioselective C-H Activation/Nucleophilic [3 + 2] Annulation toward Chiral Bridged Bicycles. J Am Chem Soc 2024; 146:15576-15586. [PMID: 38753821 DOI: 10.1021/jacs.4c04623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
Abstract
Selective synthesis of chiral bridged (hetero)bicyclic scaffolds via asymmetric C-H activation constitutes substantial challenges due to the multiple reactivities of strained bicyclic structures. Herein, we develop the domino transformations through an unprecedented cobalt-catalyzed enantioselective C-H activation/nucleophilic [3 + 2] annulation with symmetrical bicyclic alkenes. The methods offer straightforward access to a wide range of chiral molecules bearing [2.2.1]-bridged bicyclic cores with four and five consecutive stereocenters in a single step. Two elaborate salicyloxazoline (Salox) ligands were synthesized based on the rational design and mechanistic understanding. The well-defined chiral pockets generated from asymmetric coordination around the trivalent cobalt catalyst direct the orientation of bicyclic alkenes, leading to excellent enantioselectivity.
Collapse
Affiliation(s)
- Fan-Rui Huang
- Center of Chemistry for Frontier Technologies, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Qi-Jun Yao
- Center of Chemistry for Frontier Technologies, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Peng Zhang
- Center of Chemistry for Frontier Technologies, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Ming-Ya Teng
- Center of Chemistry for Frontier Technologies, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Jia-Hao Chen
- Center of Chemistry for Frontier Technologies, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Lu-Chen Jiang
- Center of Chemistry for Frontier Technologies, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Bing-Feng Shi
- Center of Chemistry for Frontier Technologies, Department of Chemistry, Zhejiang University, Hangzhou 310027, China
- College of Material Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou, Zhejiang 311121, China
- College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, Zhejiang 314001, China
| |
Collapse
|
9
|
Cosio M, Lee SR, Lai Q, Bhuvanesh N, Zhou J, Ozerov OV. Dimeric Rh Complexes Supported by a Bridging Phosphido/Bis(Phosphine) PPP Ligand. Organometallics 2024; 43:947-953. [PMID: 38756991 PMCID: PMC11094786 DOI: 10.1021/acs.organomet.3c00492] [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: 11/29/2023] [Revised: 04/05/2024] [Accepted: 04/05/2024] [Indexed: 05/18/2024]
Abstract
Rh complexes of a tridentate PPP ligand bearing 1,2-pyrrolediyl linkers have been prepared, including examples with the central P donor being either a phosphine or a phosphide. Three bimetallic Rh complexes containing the diamandoid Rh2P2 core (P = phosphido) have been structurally and spectroscopically characterized. The Rh-Rh interaction in these three dimers was examined by way of structural comparisons and DFT investigations.
Collapse
Affiliation(s)
- Mario
N. Cosio
- Department
of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Samuel R. Lee
- Department
of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Qingheng Lai
- Department
of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Nattamai Bhuvanesh
- Department
of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| | - Jia Zhou
- State
Key Laboratory of Urban Water Resource and Environment, School of
Science, Harbin Institute of Technology, Shenzhen 518055, China
| | - Oleg V. Ozerov
- Department
of Chemistry, Texas A&M University, College Station, Texas 77842, United States
| |
Collapse
|
10
|
Xu S, Mi R, Zheng G, Li X. Cobalt- or rhodium-catalyzed synthesis of 1,2-dihydrophosphete oxides via C-H activation and formal phosphoryl migration. Chem Sci 2024; 15:6012-6021. [PMID: 38665527 PMCID: PMC11040647 DOI: 10.1039/d4sc00649f] [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: 01/28/2024] [Accepted: 03/11/2024] [Indexed: 04/28/2024] Open
Abstract
A highly stereo- and chemoselective intermolecular coupling of diverse heterocycles with dialkynylphosphine oxides has been realized via cobalt/rhodium-catalyzed C-H bond activation. This protocol provides an efficient synthetic entry to functionalized 1,2-dihydrophosphete oxides in excellent yields via the merger of C-H bond activation and formal 1,2-migration of the phosphoryl group. Compared with traditional methods of synthesis of 1,2-dihydrophosphetes that predominantly relied on stoichiometric metal reagents, this catalytic system features high efficiency, a relatively short reaction time, atom-economy, and operational simplicity. Photophysical properties of selected 1,2-dihydrophosphete oxides are also disclosed.
Collapse
Affiliation(s)
- Shengbo Xu
- School of Chemistry and Chemical Engineering, Shaanxi Normal University (SNNU) Xi'an 710062 P. R. China
| | - Ruijie Mi
- Institute of Molecular Science and Engineering, Institute of Frontier and Interdisciplinary Sciences, Shandong University Qingdao 266237 P. R. China
| | - Guangfan Zheng
- Department of Chemistry, Northeast Normal University Changchun 130024 P. R. China
| | - Xingwei Li
- School of Chemistry and Chemical Engineering, Shaanxi Normal University (SNNU) Xi'an 710062 P. R. China
- Institute of Molecular Science and Engineering, Institute of Frontier and Interdisciplinary Sciences, Shandong University Qingdao 266237 P. R. China
| |
Collapse
|
11
|
Coburger P, Buzanich AG, Emmerling F, Abbenseth J. Combining geometric constraint and redox non-innocence within an ambiphilic PBiP pincer ligand. Chem Sci 2024; 15:6036-6043. [PMID: 38665539 PMCID: PMC11040644 DOI: 10.1039/d4sc00197d] [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: 01/09/2024] [Accepted: 03/16/2024] [Indexed: 04/28/2024] Open
Abstract
The synthesis of the first pincer ligand featuring a strictly T-shaped group 15 element and its coordination behaviour towards transition metals is described. The platform is itself derived from a trianionic redox non-innocent NNN scaffold. In addition to providing a rigid coordination environment to constrain a Bi centre in a T-shaped geometry to manipulate its frontier molecular orbital constitution, the NNN chelate displays highly covalent bonding towards the geometrically constrained Bi centre. The formation of intriguing ambiphilic Bi-M bonding interactions is demonstrated upon formation of a pincer complex as well as a multimetallic cluster. All compounds are comprehensively characterised by spectroscopic methods including X-ray Absorption Near Edge Structure (XANES) spectroscopy and complemented by DFT calculations.
Collapse
Affiliation(s)
- Peter Coburger
- Department of Inorganic Chemistry, Technische Universität München Lichtenbergstr. 4 85747 Garching Germany
| | - Ana Guilherme Buzanich
- Department of Materials Chemistry, Federal Institute for Materials Research and Testing Richard-Willstätter-Str. 11 12489 Berlin Germany
| | - Franziska Emmerling
- Department of Materials Chemistry, Federal Institute for Materials Research and Testing Richard-Willstätter-Str. 11 12489 Berlin Germany
- Institut für Chemie, Humboldt-Universität zu Berlin Brook-Taylor-Str. 2 12489 Berlin Germany
| | - Josh Abbenseth
- Institut für Chemie, Humboldt-Universität zu Berlin Brook-Taylor-Str. 2 12489 Berlin Germany
| |
Collapse
|
12
|
Leong DW, Shao Y, Ni Z, Bhuvanesh N, Ozerov OV. A bis(PCN) palladium pincer complex with a remarkably planar 2,5-diarylpyrazine core. Dalton Trans 2024; 53:6520-6523. [PMID: 38563468 DOI: 10.1039/d3dt04248k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
A bimetallic Pd complex of a bis(pincer) with a diarylpyrazine core has been prepared. The complex demonstrates near-perfect coplanarity of the aromatic core, is fluorescent under UV irradiation, and displays two quasi-reversible reduction events.
Collapse
Affiliation(s)
- Derek W Leong
- Department of Chemistry, Texas A&M University, College Station, TX 77842, USA.
| | - Yanwu Shao
- Department of Chemistry, Texas A&M University, College Station, TX 77842, USA.
| | - Zhen Ni
- Department of Chemistry, Texas A&M University, College Station, TX 77842, USA.
| | - Nattamai Bhuvanesh
- Department of Chemistry, Texas A&M University, College Station, TX 77842, USA.
| | - Oleg V Ozerov
- Department of Chemistry, Texas A&M University, College Station, TX 77842, USA.
| |
Collapse
|
13
|
Ramspoth TF, Kootstra J, Harutyunyan SR. Unlocking the potential of metal ligand cooperation for enantioselective transformations. Chem Soc Rev 2024; 53:3216-3223. [PMID: 38381077 PMCID: PMC10985679 DOI: 10.1039/d3cs00998j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Indexed: 02/22/2024]
Abstract
Metal-ligand cooperation, in which both the metal and the ligand of a transition metal complex actively participate in chemical transformations leading to enhanced reactivity or selectivity in chemical reactions, has emerged as a powerful and versatile concept in catalysis. This Viewpoint discusses the development trajectory of transition metal-based complexes as catalysts in (de)hydrogenative processes, in particular those cases where metal-ligand cooperation has been invoked to rationalise the observed high reactivities and excellent selectivities. The historical context, mechanistic aspects and current applications are discussed with the suggestion to explore the potential of the MLC mode of action of such catalysts in enantioselective transformations beyond (de)hydrogenative processes.
Collapse
Affiliation(s)
- Tizian-Frank Ramspoth
- Institute for Chemistry, University of Groningen Institution Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
| | - Johanan Kootstra
- Institute for Chemistry, University of Groningen Institution Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
| | - Syuzanna R Harutyunyan
- Institute for Chemistry, University of Groningen Institution Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
| |
Collapse
|
14
|
Pecak J, Talmazan RA, Svatunek D, Kirchner K, Podewitz M. Is Mn(I) More Promising Than Fe(II)-A Comparison of Mn vs Fe Complexes for Olefin Metathesis. Organometallics 2024; 43:457-466. [PMID: 38425381 PMCID: PMC10900517 DOI: 10.1021/acs.organomet.3c00398] [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: 09/15/2023] [Revised: 01/05/2024] [Accepted: 01/11/2024] [Indexed: 03/02/2024]
Abstract
Olefin metathesis is one of the most significant transformations in organic chemistry and is an excellent example for efficient homogeneous catalysis. Although most currently used catalysts are primarily based on 4d and 5d metals, cycloaddition and cycloreversion reactions can also be attributed to first-row transition metals, such as Fe. Surprisingly, the potential of Mn(I)-based catalysts for olefin metathesis has been unexplored despite their prominence in homogeneous catalysis and their diagonal relationship to Ru(II). In the present study, we have investigated the prospective capabilities of Mn complexes for cycloaddition and reversion reactions using density functional theory. Therefore, we have initially compared the literature known iron model systems and their isoelectronic Mn counterparts regarding their reactivity and electronic structure. Next, we constructed potential Mn complexes derived from synthetically accessible species, including carbonyl ligands and obeying octahedral geometry. Based on thermodynamic parameters and the calculation of electronic descriptors, we were able to validate the isodiagonal relationship. Our study serves as guidance for the experimental chemist.
Collapse
Affiliation(s)
- Jan Pecak
- Institute
of Materials Chemistry, TU Wien, Getreidemarkt 9, Vienna 1060, Austria
| | - Radu A. Talmazan
- Institute
of Materials Chemistry, TU Wien, Getreidemarkt 9, Vienna 1060, Austria
| | - Dennis Svatunek
- Institute
of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9, Vienna 1060, Austria
| | - Karl Kirchner
- Institute
of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9, Vienna 1060, Austria
| | - Maren Podewitz
- Institute
of Materials Chemistry, TU Wien, Getreidemarkt 9, Vienna 1060, Austria
| |
Collapse
|
15
|
Pennamuthiriyan A, Rengan R. Nickel Pincer Complexes Catalyzed Sustainable Synthesis of 3,4-Dihydro-2 H-1,2,4-benzothiadiazine-1,1-dioxides via Acceptorless Dehydrogenative Coupling of Primary Alcohols. J Org Chem 2024; 89:2494-2504. [PMID: 38326039 DOI: 10.1021/acs.joc.3c02508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
We report the atom-economic and sustainable synthesis of biologically important 3,4-dihydro-2H-1,2,4-benzothiadiazine-1,1-dioxide (DHBD) derivatives from readily available aromatic primary alcohols and 2-aminobenzenesulfonamide catalyzed by nickel(II)-N∧N∧S pincer-type complexes. The synthesized nickel complexes have been well-studied by elemental and spectroscopic (FT-IR, NMR, and HRMS) analyses. The solid-state molecular structure of complex 2 has been authenticated by a single-crystal X-ray diffraction study. Furthermore, a series of 3,4-dihydro-2H-1,2,4-benzothiadiazine-1,1-dioxide derivatives have been synthesized (24 examples) utilizing a 3 mol % Ni(II) catalyst through acceptorless dehydrogenative coupling of benzyl alcohols with benzenesulfonamide. Gratifyingly, the catalytic protocol is highly selective with the yield up to 93% and produces eco-friendly water/hydrogen gas as byproducts. The control experiments and plausible mechanistic investigations indicate that the coupling of the in situ generated aldehyde with benzenesulfonamide leads to the desired product. In addition, a large-scale synthesis of one of the thiadiazine derivatives unveils the synthetic usefulness of the current methodology.
Collapse
Affiliation(s)
- Anandaraj Pennamuthiriyan
- Centre for Organometallic Chemistry, School of Chemistry, Bharathidasan University, Tiruchirappalli 620024, Tamilnadu, India
| | - Ramesh Rengan
- Centre for Organometallic Chemistry, School of Chemistry, Bharathidasan University, Tiruchirappalli 620024, Tamilnadu, India
| |
Collapse
|
16
|
Donnelly LJ, Lin JB, Gelfand BS, Chang CY, Piers WE. Ruthenium polyhydrides supported by rigid PCP pincer ligands: dynamic behaviour and reactions with CO 2. Dalton Trans 2024; 53:1862-1869. [PMID: 38179611 DOI: 10.1039/d3dt04014c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2024]
Abstract
Two rigid β-elimination immune PCcarbeneP pincer ligands, differing in their electron donor properties by variation of the substitution pattern on the aromatic linker arms, were complexed to ruthenium to form the dichlorides LRRuCl2 (R = H or NMe2). These compounds were converted to hydrido chlorides by treatment with dihydrogen (H2) and a base. By converting to tert-butoxide derivatives in situ under an atmosphere of H2, the poly hydride PCalkylP complexes LHRRu(H)3 compounds were generated. In these complexes, H2 has added across the RuC bond in the PCcarbeneP starting materials. The polyhydrides are dynamic in solution and extensive NMR studies helped to elucidate the speciation and fluxional processes operative in this dynamic system. The polyhydride complexes react rapidly with CO2 to give the PCcarbeneP formato hydride complexes LRRu(H)-κ2-O2CH. For R = H, the 1,2-hydride shift from the anchoring alkyl of the PCalkylP carbon to the metal is reversible, but for R = NMe2 it is irreversible. The CO2 incorporated into the formato ligand of these compounds exchanges with free CO2via a bimolecular mechanism that is more rapid for R = NMe2 than for R = H; plausible explanations for this observation are proffered. Experiments designed to evaluate the efficacy of the R = NMe2 formato hydride complex as a catalyst precursor for CO2 hydrogenation to formate salts reveal poor performance in comparison to state-of-the-art ruthenium-based catalysts. This is due primarily to the precipitation of a dimeric μ-κ2-κ1-CO3 carbonate complex that is not an active catalyst for the reaction.
Collapse
Affiliation(s)
- Laurie J Donnelly
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada.
| | - Jian-Bin Lin
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada.
| | - Benjamin S Gelfand
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada.
| | - Chia Yun Chang
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada.
| | - Warren E Piers
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada.
| |
Collapse
|
17
|
Besmer ML, Schwitter F, Battistin F, Braband H, Fox T, Spingler B, Alberto R. Induced fac- mer rearrangements in {M(CO) 3} + complexes (M = Re, 99(m)Tc) by a PNP ligand. Dalton Trans 2024; 53:1434-1438. [PMID: 38189151 DOI: 10.1039/d3dt03992g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
The fac-mer rearrangements in [MX3(CO)3]2- (M = Re, 99Tc) induced by a pincer-type ligand (PNP) and a "halide scavenger" are reported. The reactions of fac-[99mTc(CO)3(OH2)3]+ or [99mTcO4]- in saline both yield mer-[99mTc(PNP)(CO)3]+, the first example of a mer-{99mTc(CO)3}+ type complex. In contrast, reactions with terpyridine (terpy) only gave the facial κ2-terpy complexes with Re and 99Tc.
Collapse
Affiliation(s)
- Manuel Luca Besmer
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
| | - Flurina Schwitter
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
| | - Federica Battistin
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
| | - Henrik Braband
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
| | - Thomas Fox
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
| | - Bernhard Spingler
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
| | - Roger Alberto
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
| |
Collapse
|
18
|
Huang J, Gao Q, Zhong T, Chen S, Lin W, Han J, Xie J. Photoinduced copper-catalyzed C-N coupling with trifluoromethylated arenes. Nat Commun 2023; 14:8292. [PMID: 38092783 PMCID: PMC10719352 DOI: 10.1038/s41467-023-44097-y] [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: 08/29/2023] [Accepted: 11/30/2023] [Indexed: 12/17/2023] Open
Abstract
Selective defluorinative functionalization of trifluoromethyl group (-CF3) is an attractive synthetic route to the pharmaceutically privileged fluorine-containing moiety. Herein, we report a strategy based on photoexcited copper catalysis to activate the C-F bond of di- or trifluoromethylated arenes for divergent radical C-N coupling with carbazoles and aromatic amines. The use of different ligands can tune the reaction products diversity. A range of substituted, structurally diverse α,α-difluoromethylamines can be obtained from trifluoromethylated arenes via defluorinative C-N coupling with carbazoles, while an interesting double defluorinative C-N coupling is ready for difluoromethylated arenes. Based on this success, a carbazole-centered PNP ligand is designed to be an optimal ligand, enabling a copper-catalyzed C-N coupling for the construction of imidoyl fluorides from aromatic amines through double C-F bond functionalization. Interestingly, a 1,2-difluoroalkylamination strategy of styrenes is also developed, delivering γ,γ-difluoroalkylamines, a bioisostere to β-aminoketones, in synthetically useful yields. The DFT studies reveal an inner-sphere electron transfer mechanism for Cu-catalyzed selective activation of C(sp3)-F bonds.
Collapse
Affiliation(s)
- Jun Huang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Qi Gao
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Tao Zhong
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Shuai Chen
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Wei Lin
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
- School of Chemistry and Environmental Engineering, Jiangsu University of Technology, Changzhou, 213001, China
| | - Jie Han
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China.
| | - Jin Xie
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China.
| |
Collapse
|
19
|
Culver DB, Boncella JM. Double Intramolecular 1,2 C-H Addition of o-Methyl Groups To Form Ruthenium Pincer Double Tuck-In Complexes. Inorg Chem 2023; 62:19383-19388. [PMID: 37971401 DOI: 10.1021/acs.inorgchem.3c02499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
Ruthenium pincer complexes have a rich history of coordination and reaction chemistries. In this work, we report our discoveries of previously unreported Ru pincer coordination geometries. We found that mono tuck-in κ4-ArPNHPRuLCl complexes react with NaN(SiMe3)2 producing double tuck-in mer-κ5-ArPNHPRuL complexes. Interestingly, when κ4-MesPNHPRuCl is dehydrohalogenated, the resulting double tuck-in complex binds N2, forming the nitrogen complex κ5-MesPNHPRuN2. The mer-κ5-ArPNHPRuL complexes thermally isomerize to the fac-κ5-ArPNHPRuL isomers, which is an uncommon reaction for pincer complexes. The mer-κ5-ArPNHPRuL complexes react with CO and CO2 to form amide κ4-ArPNHPRu(CO)L or carbamate κ5-ArPN(CO2)PRuL complexes, respectively, supporting the hypothesis that the κ4-ArPNPRuL amide intermediates are accessible and reactive.
Collapse
Affiliation(s)
- Damien B Culver
- Washington State University, Pullman, Washington 99164, United States
| | - James M Boncella
- Washington State University, Pullman, Washington 99164, United States
- Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| |
Collapse
|
20
|
Mao JX, Chang J, Zhang J, Chen X. Structures of nickel chloride and thiolate complexes supported by PCN and POCOP pincer ligands and catalytic reactivity of the chloride complexes. Dalton Trans 2023; 52:17485-17492. [PMID: 37955433 DOI: 10.1039/d3dt03109h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2023]
Abstract
Nickel chloride and thiolate complexes supported by benzene-pyridine-based nonsymmetrical PCN pincer ligands, [2-(tBu2PO)-6-(2-pyrindinyl-4-R)-C6H3]NiX (R = H, CH3, CF3; X = Cl, SH, SPh), were synthesized and fully characterized. The structures of these complexes and the catalytic reactivity of the chloride complexes were investigated along with the related POCOP counterparts [2,6-(tBu2PO)2C6H3]NiX (X = Cl, SH). It was found that the composition and substitution of the pincer backbone evidently influence the structures and catalytic reactivity. The Ni-P and Ni-Cipso bond lengths in the PCN complexes are significantly shorter than those in the POCOP complex. The Ni-Cl and Ni-S bond lengths in the PCN complexes are longer than those in the POCOP complexes. An electron rich pyrindinyl ring in the PCN complexes makes the Ni-Cl bond longer. The Ni-N bond length is more sensitive to the auxiliary ligand compared with the Ni-P bond length in the PCN complexes. The PCN chloride complexes were found to be active catalysts for selective hydration of nitriles to primary amides in the presence of NaOH at 80 °C and the catalytic activity increases with the increase of electron richness of the pyridinyl ring. However, the corresponding POCOP counterpart is inactive under the same conditions.
Collapse
Affiliation(s)
- Jia-Xue Mao
- Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China.
| | - Jiarui Chang
- Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China.
| | - Jie Zhang
- Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China.
| | - Xuenian Chen
- Henan Key Laboratory of Boron Chemistry and Advanced Energy Materials, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Centre of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China.
- College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou, Henan 450001, China
| |
Collapse
|
21
|
Martínez-Vivas S, Gusev DG, Poyatos M, Peris E. Tuning the Catalytic Activity of a Pincer Complex of Rhodium(I) by Supramolecular and Redox Stimuli. Angew Chem Int Ed Engl 2023; 62:e202313899. [PMID: 37792812 DOI: 10.1002/anie.202313899] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 10/02/2023] [Accepted: 10/03/2023] [Indexed: 10/06/2023]
Abstract
We report the rhodium(I) complex [Rh(CNC-NDI)(CO)]+ , in which CNC-NDI refers to a pincer-CNC ligand decorated with a naphthalenediimide moiety. Due to the presence of the planar CNC ligand and the naphthalenediimide moiety, the electronic nature of the complex can be modulated by means of supramolecular and redox stimuli, respectively. The metal complex shows a strong π-π-stacking interaction with coronene. This interaction has an impact on the electron-richness of the metal, as demonstrated by the shifting of the ν(CO) stretching band to a lower frequency. The addition of tetrabutylammonium fluoride facilitates the sequential one- and two-electron reduction of the NDI moiety of the ligand, thus resulting in a situation in which the ligand can increase its electron-donor strength in two levels. The nature of the interaction with the fluoride anion was studied computationally. The catalytic activity of the [Rh(CNC-NDI)(CO)]+ complex was tested in the cycloisomerization of alkynoic acids, where it is observed that the activity of the catalyst can be modulated between four levels of activity, which correspond to i) the use of the unmodified catalyst, ii) catalyst+coronene, iii) catalyst+2 equivalents of fluoride, and iv) catalyst+5 equivalents of fluoride.
Collapse
Affiliation(s)
- Sebastián Martínez-Vivas
- Institute of Advanced Materials (INAM), Universitat Jaume I, Av. Vicente Sos Baynat s/n., Castellón, E-12071, Spain
| | - Dmitry G Gusev
- Department of Chemistry and Biochemistry, Wilfrid Laurier University, 75 University Avenue West, Waterloo, Ontario, N2 L 3 C5, Canada
| | - Macarena Poyatos
- Institute of Advanced Materials (INAM), Universitat Jaume I, Av. Vicente Sos Baynat s/n., Castellón, E-12071, Spain
| | - Eduardo Peris
- Institute of Advanced Materials (INAM), Universitat Jaume I, Av. Vicente Sos Baynat s/n., Castellón, E-12071, Spain
| |
Collapse
|
22
|
Ameskal M, Taakili R, Gulyaeva ES, Duhayon C, Willot J, Lugan N, Lepetit C, Valyaev DA, Canac Y. Phosphine-NHC-Phosphonium Ylide Pincer Ligand: Complexation with Pd(II) and Unconventional P-Coordination of the Ylide Moiety. Inorg Chem 2023. [PMID: 37996076 DOI: 10.1021/acs.inorgchem.3c03025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
Abstract
An efficient synthesis of two pincer preligands [Ph2PCH(R)ImCH2CH2CH2PPh3]X2 (R = H, X = OTf; R = Ph, X = BF4) was developed. Subsequent reactions with PdCl2 and an excess of Cs2CO3 led to the formation of highly stable cationic ortho-metalated Pd(II) complexes [(P,C,C,C)Pd]X exhibiting phosphine, NHC, phosphonium ylide, and σ-aryl donor extremities. The protonation of one of the latter complexes with R = H affords the Pd(II) complex [(P,C,C)Pd(MeCN)](OTf)2 bearing an unprecedented nonsymmetrical NHC core pincer scaffold with a 5,6-chelating framework. The overall donor properties of this phosphine-NHC-phosphonium ylide ligand were estimated using the experimental νCN stretching frequency in the corresponding [(P,C,C)Pd(CNtBu](OTf)2 derivative and were shown to be competitive with the related bis(NHC)-phosphonium ylide and phenoxy-NHC-phosphonium ylide pincers. The presence of a phenyl substituent in the bridge between phosphine and NHC moieties in the ortho-metalated complex [(P,C,C,C)Pd](BF4) makes possible the deprotonation of this position using LDA to provide a persistent zwitterionic complex [(P,C,C,C)Pd] featuring a rare P-coordinated phosphonium ylide moiety in addition to a conventional C-coordinated one. The comparison of the 31P and 13C NMR data for these C- and P-bound phosphonium ylide fragments within the same molecule was performed for the first time, and the bonding situation in both cases was studied in detail by QTAIM and ELF topological analyses.
Collapse
Affiliation(s)
- Mohammad Ameskal
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Rachid Taakili
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Ekaterina S Gulyaeva
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
- A. N. Nesmeyanov Institute of Organoelement Compounds (INEOS), Russian Academy of Sciences, 28/1 Vavilov str., GSP-1, B-334, Moscow 119334, Russia
| | - Carine Duhayon
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Jérémy Willot
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Noël Lugan
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Christine Lepetit
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Dmitry A Valyaev
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| | - Yves Canac
- LCC-CNRS, Université de Toulouse, CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
| |
Collapse
|
23
|
Singh V, Jain H, Nath S, Adhikari D. Multielectron Redox Afforded by a Pincer Ligand Promoting Kumada Cross-Coupling Reactions. Chemistry 2023:e202303189. [PMID: 37988192 DOI: 10.1002/chem.202303189] [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: 09/29/2023] [Revised: 11/21/2023] [Accepted: 11/21/2023] [Indexed: 11/23/2023]
Abstract
The redox-active nature of a pincer has been exploited to conduct C-C cross-coupling reactions under mild conditions. A nickel complex with a NNN pincer was dimeric in the solid state, and the structure displayed a Ni2 N2 diamond core. In the dimeric structure, both ligand backbones house an electron, in the iminosemiquinonate form, to keep the metal's oxidation state at +2. In the presence of an aryl Grignard reagent, only 3 mol % loading the nickel complex generates a Kumada cross-coupled product in good yield from a wide variety of aryl-X (X= I, Br, Cl) substrates. That the ligand-based radical remains responsible for promoting such a coupling reaction following a radical pathway is suggested by TEMPO quenching. Furthermore, a radical-clock experiment along with tracing product distribution unambiguously supported the radical's involvement through the catalytic cycle. A series of thorough mechanistic probation, including computational DFT analysis, disclosed the cooperative action of both redox-active pincer ligand and the metal centre to drive the reaction.
Collapse
Affiliation(s)
- Vikramjeet Singh
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, SAS Nagar, 140306, India
| | - Harshit Jain
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, SAS Nagar, 140306, India
| | - Shounak Nath
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, United States
| | - Debashis Adhikari
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, SAS Nagar, 140306, India
| |
Collapse
|
24
|
Taleb B, Jahjah R, Cornu D, Bechelany M, Al Ajami M, Kataya G, Hijazi A, El-Dakdouki MH. Exploring Hydrogen Sources in Catalytic Transfer Hydrogenation: A Review of Unsaturated Compound Reduction. Molecules 2023; 28:7541. [PMID: 38005261 PMCID: PMC10673347 DOI: 10.3390/molecules28227541] [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: 10/14/2023] [Revised: 11/06/2023] [Accepted: 11/07/2023] [Indexed: 11/26/2023] Open
Abstract
Catalytic transfer hydrogenation has emerged as a pivotal chemical process with transformative potential in various industries. This review highlights the significance of catalytic transfer hydrogenation, a reaction that facilitates the transfer of hydrogen from one molecule to another, using a distinct molecule as the hydrogen source in the presence of a catalyst. Unlike conventional direct hydrogenation, catalytic transfer hydrogenation offers numerous advantages, such as enhanced safety, cost-effective hydrogen donors, byproduct recyclability, catalyst accessibility, and the potential for catalytic asymmetric transfer hydrogenation, particularly with chiral ligands. Moreover, the diverse range of hydrogen donor molecules utilized in this reaction have been explored, shedding light on their unique properties and their impact on catalytic systems and the mechanism elucidation of some reactions. Alcohols such as methanol and isopropanol are prominent hydrogen donors, demonstrating remarkable efficacy in various reductions. Formic acid offers irreversible hydrogenation, preventing the occurrence of reverse reactions, and is extensively utilized in chiral compound synthesis. Unconventional donors such as 1,4-cyclohexadiene and glycerol have shown a good efficiency in reducing unsaturated compounds, with glycerol additionally serving as a green solvent in some transformations. The compatibility of these donors with various catalysts, substrates, and reaction conditions were all discussed. Furthermore, this paper outlines future trends which include the utilization of biomass-derived hydrogen donors, the exploration of hydrogen storage materials such as metal-organic frameworks (MOFs), catalyst development for enhanced activity and recyclability, and the utilization of eco-friendly solvents such as glycerol and ionic liquids. Innovative heating methods, diverse base materials, and continued research into catalyst-hydrogen donor interactions are aimed to shape the future of catalytic transfer hydrogenation, enhancing its selectivity and efficiency across various industries and applications.
Collapse
Affiliation(s)
- Batoul Taleb
- Platform for Research and Analysis in Environmental Sciences (PRASE), Doctoral School of Science and Technology, Lebanese University, Beirut P.O. Box 6573/14, Lebanon; (B.T.); (R.J.); (M.A.A.); (G.K.); (A.H.)
- Department of Chemistry, Faculty of Science, Beirut Arab University, Debbieh P.O. Box 11-5020, Lebanon
| | - Rabih Jahjah
- Platform for Research and Analysis in Environmental Sciences (PRASE), Doctoral School of Science and Technology, Lebanese University, Beirut P.O. Box 6573/14, Lebanon; (B.T.); (R.J.); (M.A.A.); (G.K.); (A.H.)
| | - David Cornu
- Institut Européen des Membranes (IEM), UMR 5635, University of Montpellier, ENSCM, CNRS, Place Eugène Bataillon, 34095 Montpellier, France;
| | - Mikhael Bechelany
- Institut Européen des Membranes (IEM), UMR 5635, University of Montpellier, ENSCM, CNRS, Place Eugène Bataillon, 34095 Montpellier, France;
- Applied Mathematics and Bioinformatics (CAMB), Gulf University for Science and Technology (GUST), Mubarak Al-Abdullah 32093, Kuwait
| | - Mohamad Al Ajami
- Platform for Research and Analysis in Environmental Sciences (PRASE), Doctoral School of Science and Technology, Lebanese University, Beirut P.O. Box 6573/14, Lebanon; (B.T.); (R.J.); (M.A.A.); (G.K.); (A.H.)
| | - Ghenwa Kataya
- Platform for Research and Analysis in Environmental Sciences (PRASE), Doctoral School of Science and Technology, Lebanese University, Beirut P.O. Box 6573/14, Lebanon; (B.T.); (R.J.); (M.A.A.); (G.K.); (A.H.)
- Institut Européen des Membranes (IEM), UMR 5635, University of Montpellier, ENSCM, CNRS, Place Eugène Bataillon, 34095 Montpellier, France;
| | - Akram Hijazi
- Platform for Research and Analysis in Environmental Sciences (PRASE), Doctoral School of Science and Technology, Lebanese University, Beirut P.O. Box 6573/14, Lebanon; (B.T.); (R.J.); (M.A.A.); (G.K.); (A.H.)
| | - Mohammad H. El-Dakdouki
- Department of Chemistry, Faculty of Science, Beirut Arab University, Debbieh P.O. Box 11-5020, Lebanon
| |
Collapse
|
25
|
Das A, Sankaralingam M. Are Zn(II) pincer complexes efficient apoptosis inducers? a deep insight into their activity against A549 lung cancer cells. Dalton Trans 2023; 52:14465-14476. [PMID: 37772631 DOI: 10.1039/d3dt02419a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/30/2023]
Abstract
To expand the array of chemotherapeutic drugs, earth-abundant metal complexes are found to be the future direction. In this regard, new zinc(II) complexes 1-3 of 8-aminoquinoline-based pincer ligands were synthesized, characterized and tested for their anticancer activity. The IC50 values of these complexes were estimated by an MTT assay to be 16.35-17.95 μM and 33.35-40 μM against A549 lung and MCF-7 breast cancer cells respectively. Among them, 3 was slightly better than the other complexes and, thus, subjected to detailed studies. Moreover, the ligand corresponding to 3 was less active against both the cell lines than the complex. Further, 3 showed no toxicity against normal fibroblast cell line L929, which instantly elevated the drug characteristic of our complex. An AO-EB staining assay revealed that 3 can induce apoptosis in A549, and it was quantified by flow cytometry as 22.77%. Moreover, the depolarization of the mitochondrial membrane potential determined by JC-1 staining indicated excess ROS production sites in the mitochondria, which was confirmed by carboxy-H2DCFDA staining. Interestingly, the present complexes show better activity than that of the standard drug cisplatin against A549 cells. Overall, the studies provided promising results that can be extended for clinical applications.
Collapse
Affiliation(s)
- Athulya Das
- Bioinspired & Biomimetic Inorganic Chemistry Laboratory, Department of Chemistry, National Institute of Technology Calicut, Kozhikode-673601, Kerala, India.
| | - Muniyandi Sankaralingam
- Bioinspired & Biomimetic Inorganic Chemistry Laboratory, Department of Chemistry, National Institute of Technology Calicut, Kozhikode-673601, Kerala, India.
| |
Collapse
|
26
|
Parmar SV, Deshmukh P, Sankpal R, Watharkar S, Avasare V. Machine Learning-Enabled Predictions of Condensed Fukui Functions and Designing of Metal Pincer Complexes for Catalytic Hydrogenation of CO 2. J Phys Chem A 2023; 127:8338-8346. [PMID: 37756223 DOI: 10.1021/acs.jpca.3c04494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2023]
Abstract
This research showcases the machine learning (ML)-enabled homogeneous catalyst discovery to be employed in carbon dioxide hydrogenation. To achieve the desired turnover frequency (TOF), the electrophilicity of the central metal atom is a crucial factor in transition metal pincer complexes. The condensed Fukui function is a direct measure of the catalytic performance of these pincer complexes. Herein, we demonstrate that machine learning is a convenient and effiecient method to calculate condensed Fukui functions of the central metal atom. The electrophilicity values of 202 pincer complexes were calculated by using density functional theory (DFT) to train the ML model. The test data of the experimentally established pincer complexes show a direct linkage between calculated electrophilicity and experimental TOF. Further, this data was used to develop an ML protocol to screen 2,84,062 catalyst complexes to get the electrophilicity values of the Mn, Fe, Co, and Ni transition metals encompassing various permutation combinations of PNP, PNN, NNN, and PCP pincer ligands. These findings validate the efficacy of machine learning in the rapid screening of metal pincer catalysts based on condensed Fukui functions.
Collapse
Affiliation(s)
- Saurabh V Parmar
- Department of Chemistry, Ashoka University, Sonipat, Haryana 131029, India
| | - Pratham Deshmukh
- Department of Chemistry, Sir Parashurambhau College, Pune, Maharashtra 411030, India
| | - Rutuja Sankpal
- Department of Chemistry, Sir Parashurambhau College, Pune, Maharashtra 411030, India
| | - Siddhika Watharkar
- Department of Chemistry, Sir Parashurambhau College, Pune, Maharashtra 411030, India
| | - Vidya Avasare
- Department of Chemistry, Ashoka University, Sonipat, Haryana 131029, India
- Department of Chemistry, Sir Parashurambhau College, Pune, Maharashtra 411030, India
| |
Collapse
|
27
|
Hashemi A, Bougueroua S, Gaigeot MP, Pidko EA. HiREX: High-Throughput Reactivity Exploration for Extended Databases of Transition-Metal Catalysts. J Chem Inf Model 2023; 63:6081-6094. [PMID: 37738303 PMCID: PMC10565810 DOI: 10.1021/acs.jcim.3c00660] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Indexed: 09/24/2023]
Abstract
A method is introduced for the automated analysis of reactivity exploration for extended in silico databases of transition-metal catalysts. The proposed workflow is designed to tackle two key challenges for bias-free mechanistic explorations on large databases of catalysts: (1) automated exploration of the chemical space around each catalyst with unique structural and chemical features and (2) automated analysis of the resulting large chemical data sets. To address these challenges, we have extended the application of our previously developed ReNeGate method for bias-free reactivity exploration and implemented an automated analysis procedure to identify the classes of reactivity patterns within specific catalyst groups. Our procedure applied to an extended series of representative Mn(I) pincer complexes revealed correlations between structural and reactive features, pointing to new channels for catalyst transformation under the reaction conditions. Such an automated high-throughput virtual screening of systematically generated hypothetical catalyst data sets opens new opportunities for the design of high-performance catalysts as well as an accelerated method for expert bias-free high-throughput in silico reactivity exploration.
Collapse
Affiliation(s)
- Ali Hashemi
- Inorganic
Systems Engineering, Department of Chemical Engineering, Faculty of
Applied Sciences, Delft University of Technology, Van der Maasweg 9, Delft 2629 HZ, The Netherlands
| | - Sana Bougueroua
- Laboratoire
Analyse et Modélisation pour la Biologie et l’Environnement
(LAMBE) UMR8587, Paris-Saclay, Univ Evry,
CY Cergy Paris Université, CNRS, LAMBE UMR8587, Evry-Courcouronnes 91025, France
| | - Marie-Pierre Gaigeot
- Laboratoire
Analyse et Modélisation pour la Biologie et l’Environnement
(LAMBE) UMR8587, Paris-Saclay, Univ Evry,
CY Cergy Paris Université, CNRS, LAMBE UMR8587, Evry-Courcouronnes 91025, France
| | - Evgeny A. Pidko
- Inorganic
Systems Engineering, Department of Chemical Engineering, Faculty of
Applied Sciences, Delft University of Technology, Van der Maasweg 9, Delft 2629 HZ, The Netherlands
| |
Collapse
|
28
|
Singh S, Shinde VN, Kumar S, Meena N, Bhuvanesh N, Rangan K, Kumar A, Joshi H. Mono and Dinuclear Palladium Pincer Complexes of NNSe Ligand as a Catalyst for Decarboxylative Direct C-H Heteroarylation of (Hetero)arenes. Chem Asian J 2023; 18:e202300628. [PMID: 37602812 DOI: 10.1002/asia.202300628] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/18/2023] [Accepted: 08/18/2023] [Indexed: 08/22/2023]
Abstract
This report describes the synthesis of a new NNSe pincer ligand and its mono- and dinuclear palladium(II) pincer complexes. In the absence of a base, a dinuclear palladium pincer complex (C1) was isolated, while in the presence of Et3 N base a mononuclear palladium pincer complex (C2) was obtained. The new ligand and complexes were characterized using techniques like 1 H, 13 C{1 H} nuclear magnetic resonance (NMR), fourier transform infrared (FTIR), high-resolution mass spectrometry (HRMS), ultraviolet-visible (UV-Visible), and cyclic voltammetry. Both the complexes showed pincer coordination mode with a distorted square planar geometry. The complex C1 has two pincer ligands attached through a Pd-Pd bond in a dinuclear pincer fashion. The air and moisture-insensitive, thermally robust palladium pincer complexes were used as the catalyst for decarboxylative direct C-H heteroarylation of (hetero)arenes. Among the complexes, dinuclear pincer complex C1 showed better catalytic activity. A variety of (hetero)arenes were successfully activated (43-87 % yield) using only 2.5 mol % of catalyst loading under mild reaction conditions. The PPh3 and Hg poisoning experiments suggested a homogeneous nature of catalysis. A plausible reaction pathway was proposed for the dinuclear palladium pincer complex catalyzed decarboxylative C-H bond activation reaction of (hetero)arenes.
Collapse
Affiliation(s)
- Sohan Singh
- ISC Laboratory, Department of Chemistry, School of Chemical Sciences and Pharmacy, Central University of Rajasthan, NH-8, Bandarsindri, Ajmer, Rajasthan, 305817, India
| | - Vikki N Shinde
- Department of Chemistry, Birla Institute of Technology and Science, Pilani, Pilani Campus, Pilani, 333031, India
| | - Sunil Kumar
- ISC Laboratory, Department of Chemistry, School of Chemical Sciences and Pharmacy, Central University of Rajasthan, NH-8, Bandarsindri, Ajmer, Rajasthan, 305817, India
| | - Neha Meena
- Department of Chemistry, Birla Institute of Technology and Science, Pilani, Pilani Campus, Pilani, 333031, India
| | - Nattamai Bhuvanesh
- Department of Chemistry, Texas A&M University, PO Box 30012, College Station, Texas, 77842-3012, USA
| | - Krishnan Rangan
- Department of Chemistry, Birla Institute of Technology and Science Pilani, Hyderabad Campus, Telangana, 500078, India
| | - Anil Kumar
- Department of Chemistry, Birla Institute of Technology and Science, Pilani, Pilani Campus, Pilani, 333031, India
| | - Hemant Joshi
- ISC Laboratory, Department of Chemistry, School of Chemical Sciences and Pharmacy, Central University of Rajasthan, NH-8, Bandarsindri, Ajmer, Rajasthan, 305817, India
| |
Collapse
|
29
|
Baweja S, Kazimir A, Lönnecke P, Hey-Hawkins E. Modular Synthesis of Phosphino Hydrazones and Their Use as Ligands in a Palladium-Catalysed Cu-Free Sonogashira Cross-Coupling Reaction. Chempluschem 2023; 88:e202300163. [PMID: 37155325 DOI: 10.1002/cplu.202300163] [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: 03/29/2023] [Revised: 05/04/2023] [Accepted: 05/08/2023] [Indexed: 05/10/2023]
Abstract
Phosphino hydrazones represent a versatile class of nitrogen-containing phosphine ligands. Herein, we report a modular synthesis of phosphino hydrazone ligands by hydrazone condensation reaction of three different aryl hydrazines with 3-(diphenylphosphino)propanal (PCHO). Complexation reactions of these phosphino hydrazone ligands with palladium(II) and platinum(II) were investigated and the catalytic activity of the palladium(II) complexes was explored in a Cu-free Sonogashira cross-coupling reaction achieving yields up to 96 %. Additionally it was shown that the catalytically active species is homogeneous.
Collapse
Affiliation(s)
- Saral Baweja
- Faculty of Chemistry and Mineralogy Institute of Inorganic Chemistry, Leipzig University, Johannisallee 29, 04103, Leipzig, Germany
| | - Aleksandr Kazimir
- Faculty of Chemistry and Mineralogy Institute of Inorganic Chemistry, Leipzig University, Johannisallee 29, 04103, Leipzig, Germany
| | - Peter Lönnecke
- Faculty of Chemistry and Mineralogy Institute of Inorganic Chemistry, Leipzig University, Johannisallee 29, 04103, Leipzig, Germany
| | - Evamarie Hey-Hawkins
- Faculty of Chemistry and Mineralogy Institute of Inorganic Chemistry, Leipzig University, Johannisallee 29, 04103, Leipzig, Germany
| |
Collapse
|
30
|
Höhn V, Feuerstein W, Rehak FR, Kehry M, Lebedkin S, Kappes MM, Klopper W, Breher F. Non-Palindromic C∧C∧P Platinum and Palladium Pincer Complexes Showing Intense Phosphorescence via Direct Spin-Forbidden S 0 → T 1 Excitation. Inorg Chem 2023; 62:15627-15640. [PMID: 37682719 DOI: 10.1021/acs.inorgchem.3c02339] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/10/2023]
Abstract
The synthesis of C∧C∧P pre-ligands based on a dicyclohexylphosphine-substituted biphenyl framework is reported. The pre-ligands form the respective non-palindromic pincer complexes of PtII and PdII via double oxidative addition and subsequent comproportionation or C-H activation. The complexes of PtII as well as PdII emit similar green phosphorescence efficiently in the solid state, the former also in solution albeit with less intensity. The most fascinating photophysical feature, however, is a direct singlet-triplet (S0 → T1) excitation of this phosphorescence in the spectral window between the emission and the major singlet-singlet UV absorption. The S0 → T1 excitation spectra show a rich vibronic pattern, which is especially pronounced for the solid samples at cryogenic temperatures. The molar extinction of the lowest-energy singlet-triplet absorption band of the homologous Pt and Pd complexes as well as that of the Pt complex with a different (NHC) ancillary ligand were determined in tetrahydrofuran solutions. Quantum efficiencies of triplet formation (by intersystem crossing) via the "standard" excitation pathway S0 → Sn → T1 were determined for the Pt complexes and found to be different in dependence of the ancillary ligand.
Collapse
Affiliation(s)
- Verena Höhn
- Karlsruhe Institute of Technology (KIT), Institute of Inorganic Chemistry, Engesserstraße 15, 76131 Karlsruhe, Germany
| | - Wolfram Feuerstein
- Karlsruhe Institute of Technology (KIT), Institute of Inorganic Chemistry, Engesserstraße 15, 76131 Karlsruhe, Germany
| | - Florian R Rehak
- Karlsruhe Institute of Technology (KIT), Institute of Physical Chemistry, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany
| | - Max Kehry
- Karlsruhe Institute of Technology (KIT), Institute of Physical Chemistry, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany
| | - Sergei Lebedkin
- Karlsruhe Institute of Technology (KIT), Institute of Nanotechnology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Manfred M Kappes
- Karlsruhe Institute of Technology (KIT), Institute of Nanotechnology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Wim Klopper
- Karlsruhe Institute of Technology (KIT), Institute of Physical Chemistry, Fritz-Haber-Weg 2, 76131 Karlsruhe, Germany
| | - Frank Breher
- Karlsruhe Institute of Technology (KIT), Institute of Inorganic Chemistry, Engesserstraße 15, 76131 Karlsruhe, Germany
| |
Collapse
|
31
|
Esfandiari M, Mohammadnezhad G, Akintola O, Otto F, Fritz T, Plass W. Sustainable catalysts for efficient triazole synthesis: an immobilized triazine-based copper-NNN pincer complex on TiO 2. Dalton Trans 2023; 52:11875-11885. [PMID: 37560800 DOI: 10.1039/d3dt02118a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
The multistep synthesis of a hybrid material based on a TiO2 core with an immobilized triazine-based copper(II)-NNN pincer complex is reported. The formation of the material was confirmed by FT-IR spectroscopy and elemental and thermogravimetric analyses, and the loading by copper ions was quantified by ICP/OES analysis. The properties of the hybrid material were further investigated by X-ray photoelectron spectroscopy (XPS), contiuous wave electron spin resonance (CW-ESR), UV-vis spectroscopy, and argon sorption. Efficient and regioselective synthesis of 1,4-disubstituted 1,2,3-triazoles was achieved by employing the hybrid material as a catalyst in a mixture of H2O/EtOH as a green solvent with excellent catalytic activity with a TOF up to 495 h-1 at 50 °C. The reusability of the prepared hybrid material in the catalytic reaction was possible over five consecutive runs without significant loss of catalytic activity. The described method represents an effective way to ensure sustainable use of pincer complexes in catalytic systems by immobilizing them on solid supports, resulting in a hybrid organic-inorganic catalyst platform.
Collapse
Affiliation(s)
- Mitra Esfandiari
- Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111, Islamic Republic of Iran.
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstraße 8, 07743 Jena, Germany.
| | | | - Oluseun Akintola
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstraße 8, 07743 Jena, Germany.
| | - Felix Otto
- Institute of Solid State Physics, Friedrich Schiller University Jena, Helmholtzweg 5, 07743 Jena, Germany
| | - Torsten Fritz
- Institute of Solid State Physics, Friedrich Schiller University Jena, Helmholtzweg 5, 07743 Jena, Germany
| | - Winfried Plass
- Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Humboldtstraße 8, 07743 Jena, Germany.
| |
Collapse
|
32
|
Grømer B, Saito S. Hydrogenation of CO 2 to MeOH Catalyzed by Highly Robust (PNNP)Ir Complexes Activated by Alkali Bases in Alcohol. Inorg Chem 2023; 62:14116-14123. [PMID: 37589272 DOI: 10.1021/acs.inorgchem.3c02412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/18/2023]
Abstract
Despite receiving significant attention, well-defined homogeneous complexes for hydrogenation of carbon dioxide (CO2) to methanol (MeOH) are scarce and suffer issues of low catalyst turnover numbers (TONs) at high catalyst concentrations and deactivation in the presence of CO and at elevated temperatures. Herein, we disclose a system deploying sterically demanded (PNNP)Ir complexes for a sustained activity for hydrogenation of CO2 to MeOH at temperatures ∼200 °C in an alcohol solvent. Through reaction optimization, we achieved a TON of ∼9000 for MeOH formation, which exceeds most active homogeneous systems reported to date, and robustness on par with or exceeding most reactive systems utilizing amine additives was demonstrated. The key to achieving sustained catalyst turnover for the system was utilizing a catalytic amount of an alkali base additive, which serves the dual purpose of facilitating more efficient outer-sphere reduction of CO2 and HCO2Et and enhancing the selectivity of MeOH over in situ formed CO.
Collapse
Affiliation(s)
- Bendik Grømer
- Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan
| | - Susumu Saito
- Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan
- Integrated Research Consortium on Chemical Sciences (IRCCS), Nagoya University, Chikusa, Nagoya 464-8602, Japan
| |
Collapse
|
33
|
Oliemuller LK, Moore CE, Thomas CM. Synthesis, Characterization, and Reactivity of a (PPP) Pincer-Ligated Manganese Carbonyl Complex: Polarity Reversal Imparted by the Electrophilic Nature of a Planar Mn-P(NR 2) 2 Fragment. Inorg Chem 2023; 62:13997-14009. [PMID: 37585359 DOI: 10.1021/acs.inorgchem.3c01988] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/18/2023]
Abstract
The bonding interactions of a synthesized pincer-ligated manganese dicarbonyl complex featuring an N-heterocyclic phosphenium (NHP+) central moiety are explored. The pincer ligand [PPP]Cl was coordinated to a manganese center using Mn(CO)5Br and 254 nm light to afford the chlorophosphine complex (PPClP)Mn(CO)2Br (2) as a mixture of halide exchange products and stereoisomers. The target dicarbonyl species (PPP)Mn(CO)2 (3) was prepared by treatment of 2 with 2 equiv of the reductant KC8. Computational investigations and analysis of structural parameters were used to elucidate multiple bonding interactions between the Mn center and the PNHP atom in 3. The generation of a product of formal H2 addition, (PPHP)Mn(CO)2H (4), was achieved through the dehydrogenation of NH3BH3, affording a 2:1 mixture of 4syn:4anti stereoisomers. The nucleophilic nature of the Mn center and the electrophilic nature of the PNHP moiety were demonstrated through hydride addition and protonation of 3 to produce K(THF)2[(PPHP)Mn(CO)2] (6) and (PPClP)Mn(CO)2H (5), respectively. The observed reactivity suggests that 3 is best described as a Mn-I/NHP+ complex, in contrast to pincer-ligated dicarbonyl manganese analogues typically assigned as MnI species.
Collapse
Affiliation(s)
- Leah K Oliemuller
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Curtis E Moore
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Christine M Thomas
- Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| |
Collapse
|
34
|
Skavenborg ML, Møller MS, Mossin S, Waite TD, McKenzie CJ. Sulfonamido-Pincer Complexes of Cu(II) and the Electrocatalysis of O 2 Reduction. Inorg Chem 2023; 62:12741-12749. [PMID: 37535840 DOI: 10.1021/acs.inorgchem.3c01262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/05/2023]
Abstract
Heteroleptic copper complexes of an asymmetrical pincer ligand containing a central anionic sulfonamide donor (pyridine-2-yl-sulfonyl)(quinolin-8-yl)-amide (psq), which contains a central anionic sulfonamido donor have been prepared. Meridional κ3-N,N″,N‴ binding with the co-ligands acetate, chloride, or acetonitrile (MeCN), trans to the central sulfonamido N-donor, is revealed by the X-ray crystal structures of [Cu(OAc)(psq)(H2O)], [CuCl(psq)]2, and [Cu(psq)(MeCN)](PF6). Either overall distorted square pyramidal or octahedral geometries of the copper atom are satisfied by coordinated water in the case of the acetate complex or interactions with periphery sulfonamido oxygen atoms on adjacent molecules in the dimeric chloride and 1D polymeric acetonitrile complexes. The cyclic voltammogram (CV) of [Cu(OAc)(psq)(H2O)] shows a quasi-reversible CuII/CuI reduction at -0.930 V (vs Fc+/Fc0, MeCN), and an irreversible CuII/CuI reduction for [Cu(psq)(MeCN)](PF6) is seen at -0.838 V. This signal is split into two quasi-reversible redox processes on the addition of 2,2,2-trifluoroethanol (TFE). This suggests that TFE pushes a solution equilibrium toward a dimeric acetate complex analogous to [CuCl(psq)]2, which shows two quasi-reversible waves at -0.666 V and -0.904 V vs Fc+/Fc0 consistent with its dimeric solid-state structure. A comparison of the CVs of [Cu(OAc)(psq)(H2O)] under either a N2 or an O2 atmosphere revealed that this complex catalyzes turnover electro-reduction of O2 to H2O2 and H2O. The rate of reaction increases on addition of a weak organic acid, and a coulombic efficiency of 48% for H2O2 was determined by iodometric titration. We propose that a CuI complex formed on electroreduction binds O2 to yield an intermediate superoxide complex. On electron and proton transfer to this species, a bifurcated route back to the O2-activating CuI complex is feasible with either release of H2O2 or O-O cleavage resulting in the liberation of H2O. The CuI complex is regenerated by subsequent reduction and protonation to close the cycle.
Collapse
Affiliation(s)
- Mathias L Skavenborg
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
- Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Mads Sondrup Møller
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| | - Susanne Mossin
- Department of Chemistry, Technical University of Denmark, Kemitorvet, Building 207, 2800 Kgs Lyngby, Denmark
| | - T David Waite
- Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Christine J McKenzie
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, 5230 Odense M, Denmark
| |
Collapse
|
35
|
Hooper RX, Mercado BQ, Holland PL. Desulfurization and N 2 Binding at an Iron Complex Derived from the C-S Activation of Benzothiophene. Organometallics 2023; 42:2019-2027. [PMID: 38282963 PMCID: PMC10810089 DOI: 10.1021/acs.organomet.3c00220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2024]
Abstract
Metal insertion into the C-S bonds of thiophenes is a facile route to interesting polydentate ligand scaffolds with C and S donors. Here, we describe iron-mediated C-S activation of a diphenylphosphine-functionalized benzothiophene proligand. Metalation of the proligand with "tetrakis(trimethylphosphine)iron" gives an initial five-coordinate, diamagnetic iron(II) species with two PMe3 ligands and a dianionic PCS pincer ligand. Upon one-electron reduction, a reactive anionic iron(I) complex is formed. This species then undergoes deep-seated changes, notably cleavage of C-S and C-P bonds in the supporting ligand. Substantial coordination sphere alterations accompany the ligand C-S bond activation, including loss of a sulfur anion from the S-Fe-C metallacycle and reorganization of the two PMe3 ligands. The resulting desulfurized six-coordinate PCC iron complex also has an N2 ligand trans to the vinyl C. Reducing this complex then cleaves a C-P bond in the appended diphenylphosphine, giving a phosphido arm. These ligand transformations demonstrate novel approaches to pincers with thiolates and phosphides, which would be difficult to synthesize using typical methods through free ligand salts.
Collapse
Affiliation(s)
- Reagan X. Hooper
- Department of Chemistry, Yale University, New Haven, Connecticut 06520
| | | | | |
Collapse
|
36
|
Dhara A, Dmitrienko A, Hussein RN, Sotomayor A, Wilson BH, Loeb SJ. A translationally active ligand based on a [2]rotaxane molecular shuttle with a 2,2'-bipyridyl core. Chem Sci 2023; 14:7215-7220. [PMID: 37416700 PMCID: PMC10321530 DOI: 10.1039/d3sc01346d] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 06/04/2023] [Indexed: 07/08/2023] Open
Abstract
A rigid H-shaped, [2]rotaxane molecular shuttle comprised of an axle containing two benzimidazole recognition sites and a central 2,2'-bipyridyl (bipy) group interlocked with a 24-crown-8 (24C8) wheel was synthesized using a threading followed by stoppering protocol. The central bipy chelating unit was shown to act as a speed bump that raised the barrier to shuttling for the [2]rotaxane. Coordination of a PtCl2 moiety to the bipy unit in a square planar geometry created an insurmountable steric barrier to shuttling. Addition of one equivalent of NaB(3,5-(CF3)2C6H3)4 removed one of the chloride ligands allowing for translation of the crown ether along the axle into the coordination sphere of the Pt(ii) centre but full shuttling of the crown ether could not be activated. In contrast, addition of Zn(ii) ions in a coordinating solvent (DMF) allowed shuttling to occur using a ligand exchange mechanism. DFT calculations showed this likely occurs via coordination of the 24C8 macrocycle to the Zn(ii) centre bound to the bipy chelate. This interplay of the rotaxane axle and wheel components is an example of a translationally active ligand that utilises the large amplitude displacement of a macrocycle along an axle in a molecular shuttle to access ligand coordination modes not possible with conventional ligand designs.
Collapse
Affiliation(s)
- Ayan Dhara
- Department of Chemistry and Biochemistry, University of Windsor Windsor ON N9B 3P4 Canada
| | - Anton Dmitrienko
- Department of Chemistry and Biochemistry, University of Windsor Windsor ON N9B 3P4 Canada
| | - Rahaf N Hussein
- Department of Chemistry and Biochemistry, University of Windsor Windsor ON N9B 3P4 Canada
| | - Ariel Sotomayor
- Department of Chemistry and Biochemistry, University of Windsor Windsor ON N9B 3P4 Canada
| | - Benjamin H Wilson
- Department of Chemistry and Biochemistry, University of Windsor Windsor ON N9B 3P4 Canada
| | - Stephen J Loeb
- Department of Chemistry and Biochemistry, University of Windsor Windsor ON N9B 3P4 Canada
| |
Collapse
|
37
|
Esteruelas MA, Moreno-Blázquez S, Oliván M, Oñate E. Competition between N, C, N-Pincer and N, N-Chelate Ligands in Platinum(II). Inorg Chem 2023; 62:10152-10170. [PMID: 37343120 PMCID: PMC11003652 DOI: 10.1021/acs.inorgchem.3c00694] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Indexed: 06/23/2023]
Abstract
Replacement of the chloride ligand of PtCl{κ3-N,C,N-[py-C6HR2-py]} (R = H (1), Me (2)) and PtCl{κ3-N,C,N-[py-O-C6H3-O-py]} (3) by hydroxido gives Pt(OH){κ3-N,C,N-[py-C6HR2-py]} (R = H (4), Me (5)) and Pt(OH){κ3-N,C,N-[py-O-C6H3-O-py]} (6). These compounds promote deprotonation of 3-(2-pyridyl)pyrazole, 3-(2-pyridyl)-5-methylpyrazole, 3-(2-pyridyl)-5-trifluoromethylpyrazole, and 2-(2-pyridyl)-3,5-bis(trifluoromethyl)pyrrole. The coordination of the anions generates square-planar derivatives, which in solution exist as a unique species or equilibria between isomers. Reactions of 4 and 5 with 3-(2-pyridyl)pyrazole and 3-(2-pyridyl)-5-methylpyrazole provide Pt{κ3-N,C,N-[py-C6HR2-py]}{κ1-N1-[R'pz-py]} (R = H; R' = H (7), Me (8). R = Me; R' = H (9), Me (10)), displaying κ1-N1-pyridylpyrazolate coordination. A 5-trifluoromethyl substituent causes N1-to-N2 slide. Thus, 3-(2-pyridyl)-5-trifluoromethylpyrazole affords equilibria between Pt{κ3-N,C,N-[py-C6HR2-py]}{κ1-N1-[CF3pz-py]} (R = H (11a), Me (12a)) and Pt{κ3-N,C,N-[py-C6HR2-py]}{κ1-N2-[CF3pz-py]} (R = H (11b), Me (12b)). 1,3-Bis(2-pyridyloxy)phenyl allows the chelating coordination of the incoming anions. Deprotonations of 3-(2-pyridyl)pyrazole and its substituted 5-methyl counterpart promoted by 6 lead to equilibria between Pt{κ3-N,C,N-[pyO-C6H3-Opy]}{κ1-N1-[R'pz-py]} (R' = H (13a), Me (14a)) with a κ-N1-pyridylpyrazolate anion, keeping the pincer coordination of the di(pyridyloxy)aryl ligand, and Pt{κ2-N,C-[pyO-C6H3(Opy)]}{κ2-N,N-[R'pz-py]} (R' = H (13c), Me (14c)) with two chelates. Under the same conditions, 3-(2-pyridyl)-5-trifluoromethylpyrazole generates the three possible isomers: Pt{κ3-N,C,N-[pyO-C6H3-Opy]}{κ1-N1-[CF3pz-py]} (15a), Pt{κ3-N,C,N-[pyO-C6H3-Opy]}{κ1-N2-[CF3pz-py]} (15b), and Pt{κ2-N,C-[pyO-C6H3(Opy)]}{κ2-N,N-[CF3pz-py]} (15c). The N1-pyrazolate atom produces a remote stabilizing effect on the chelating form, pyridylpyrazolates being better chelate ligands than pyridylpyrrolates. Accordingly, reactions of 4-6 with 2-(2-pyridyl)-3,5-bis(trifluoromethyl)pyrrole yield Pt{κ3-N,C,N-[py-C6HR2-py]}{κ1-N1-[(CF3)2C4(py)HN]} (R = H (16), Me (17)) or Pt{κ3-N,C,N-[pyO-C6H3-Opy]}{κ1-N1-[(CF3)2C4(py)HN]} (18), displaying κ1-N1-pyrrolate coordination. Complexes 7-10 are efficient green phosphorescent emitters (488-576 nm). In poly(methyl methacrylate) (PMMA) films and in dichloromethane, they experience self-quenching, due to molecular stacking. Aggregation occurs through aromatic π-π interactions, reinforced by weak platinum-platinum interactions.
Collapse
Affiliation(s)
- Miguel A. Esteruelas
- Departamento de Química
Inorgánica, Instituto de Síntesis Química y Catálisis
Homogénea (ISQCH), Centro de Innovación en Química
Avanzada (ORFEO-CINQA), Universidad de Zaragoza—CSIC, 50009 Zaragoza, Spain
| | - Sonia Moreno-Blázquez
- Departamento de Química
Inorgánica, Instituto de Síntesis Química y Catálisis
Homogénea (ISQCH), Centro de Innovación en Química
Avanzada (ORFEO-CINQA), Universidad de Zaragoza—CSIC, 50009 Zaragoza, Spain
| | - Montserrat Oliván
- Departamento de Química
Inorgánica, Instituto de Síntesis Química y Catálisis
Homogénea (ISQCH), Centro de Innovación en Química
Avanzada (ORFEO-CINQA), Universidad de Zaragoza—CSIC, 50009 Zaragoza, Spain
| | - Enrique Oñate
- Departamento de Química
Inorgánica, Instituto de Síntesis Química y Catálisis
Homogénea (ISQCH), Centro de Innovación en Química
Avanzada (ORFEO-CINQA), Universidad de Zaragoza—CSIC, 50009 Zaragoza, Spain
| |
Collapse
|
38
|
Keskin E, Arslan H. Palladium complexes containing NNN pincer type ligands and their activities in Suzuki-Miyaura cross coupling reaction. Heliyon 2023; 9:e17608. [PMID: 37519671 PMCID: PMC10372205 DOI: 10.1016/j.heliyon.2023.e17608] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 06/22/2023] [Accepted: 06/22/2023] [Indexed: 08/01/2023] Open
Abstract
Five new NNN pincer-type ligands and their palladium complexes were successfully synthesised and characterised by FT-IR, 1H NMR, 13C NMR, and UV-vis analyses. TEM analysis was used to observe the morphological character of the black residues obtained from the fourth cycle of the reusability test. Furthermore, suitable crystals of the N2,N6-bis(2-tert-butylphenyl)pyridine-2,6-dicarboxamide and its palladium complex were elucidated with the X-ray single crystal diffraction method. Both the ligand and its palladium complex crystallise in a monoclinic system with space group P21/c for the H2L4 and C2/c for the palladium complex. The structure of the pincer ligand and its palladium complex were stabilised by intramolecular and intermolecular C-H⋅⋅⋅O, C-H⋅⋅⋅N, and N-H⋅⋅⋅N contacts. A Suzuki-Miyaura cross-coupling reaction between aryl halides and phenylboronic acid was used to assess the catalytic abilities of the palladium pincer complexes. All of the prepared complexes exhibited considerable catalytic activity. However, complexes 4 (Acetonitrile-N2,N6-bis(2-tert-butylphenyl)pyridine-2,6-dicarboxamidopalladium(II)) and 5 (Acetonitrile-N2,N6-bis(2-nitrophenyl)pyridine-2,6-dicarboxamidopalladium(II)) provided almost 100% conversion with nearly 100% yield in the reaction between 4-bromotoluene and phenylboronic acid. Furthermore, these active complexes catalysed the reaction of the sterically hindered and deactivated substrates (1-Bromo-4-izobutylbenzene and 2-bromo-6-methoxynaphthalene) with phenylboronic acid, and complete conversion and yields up to 100% were achieved in a short time with the 2-bromo-6-methoxynaphthalene.
Collapse
|
39
|
Poschmann MPM, Alan Ö, Ito S, Näther C, Friedrichs G, Stock N. Systematic Study on Zirconium Chelidamates: From a Molecular Complex to a M-HOF and a MOF. Inorg Chem 2023. [PMID: 37384893 DOI: 10.1021/acs.inorgchem.3c01079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/01/2023]
Abstract
We report the synthesis and in-depth characterization of three zirconium chelidamates, a molecular complex (H8C2N)2[Zr(HL)3] (1), a porous metal-containing hydrogen-bonded organic framework (M-HOF) [Zr(H2O)2(HL)2]·xH2O (2), and a metal-organic framework (MOF) (H8C2N)2-2n[Zr(HnL)2]·x solvent (0 ≤ n ≤ 1) (3) using chelidamic acid (H3L, H5C7NO5, 4-hydroxypyridine-2,6-dicarboxylic acid) as the ligand (H8C2N+ = dimethylammonium). High-throughput investigations of the system Zr4+/H3L/HCl/DMF/H2O were carried out, which resulted in highly crystalline compounds. The crystal structures of 1 and 2 were determined by single-crystal X-ray diffraction. Single-crystal three-dimensional (3D) electron diffraction and Rietveld refinements of powder X-ray diffraction (PXRD) data had to be used to elucidate the crystal structure of 3 since only very small single crystals of about 500 nm in diameter could be obtained. In all structures, chelidamate ions act as anionic palindromic pincer ligands, and in 3, a coordinative bond is additionally formed by the aryloxy group. While dense packing of the molecular complexes is found in 1, hydrogen bonding of the molecular complexes in 2 leads to a porous network that shows flexibility depending on the water content. The three-dimensional framework structure of the Zr-MOF 3 contains a mononuclear inorganic building unit (IBU), which is very uncommon in Zr-MOF chemistry. The three compounds are stable in several organic solvents, and thermal decomposition starts above 280 °C. While the hydrogen-bonded framework 2 is only porous toward water with a water uptake of almost 3.75 mol mol-1 at p/p0 = 0.9, 3 is porous against N2, CO2, methanol, ethanol, and water with a specific Brunauer-Emmett-Teller (BET) surface area of aS,BET = 410 m2 g-1 derived from the N2 adsorption isotherm. Stability upon water adsorption covering 10 cycles between 0.5% < p/p0 < 90% for 3 is also demonstrated.
Collapse
Affiliation(s)
- Mirjam P M Poschmann
- Institute of Inorganic Chemistry, Christian-Albrechts-University Kiel, Max-Eyth-Street 2, 24118 Kiel, Germany
| | - Özge Alan
- Institute of Inorganic Chemistry, Christian-Albrechts-University Kiel, Max-Eyth-Street 2, 24118 Kiel, Germany
| | - Sho Ito
- Rigaku Corporation, 3-9-12 Matsubara-cho, Akishima 196-8666, Tokyo, Japan
| | - Christian Näther
- Institute of Inorganic Chemistry, Christian-Albrechts-University Kiel, Max-Eyth-Street 2, 24118 Kiel, Germany
| | - Gernot Friedrichs
- Institute of Physical Chemistry, Christian-Albrechts-University Kiel, Max-Eyth-Street 1, 24118 Kiel, Germany
| | - Norbert Stock
- Institute of Inorganic Chemistry, Christian-Albrechts-University Kiel, Max-Eyth-Street 2, 24118 Kiel, Germany
| |
Collapse
|
40
|
Singh V, Singh R, Hazari AS, Adhikari D. Unexplored Facet of Pincer Ligands: Super-Reductant Behavior Applied to Transition-Metal-Free Catalysis. JACS AU 2023; 3:1213-1220. [PMID: 37124293 PMCID: PMC10131200 DOI: 10.1021/jacsau.3c00077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/27/2023] [Accepted: 03/28/2023] [Indexed: 05/03/2023]
Abstract
Pincer ligands are well-established supporting ancillaries to afford robust coordination to metals across the periodic table. Despite their widespread use in developing homogeneous catalysts, the redox noninnocence of the ligand backbone is less utilized in steering catalytic transformations. This report showcases a trianionic, symmetric NNN-pincer to drive C-C cross-coupling reactions and heterocycle formation via C-H functionalization, without any coordination to transition metals. The starting substrates are aryl chlorides that can tease the limit of a catalyst's ability to promote a reductive cleavage at a much demanding potential of -2.90 V vs SCE. The reducing power of the simple trianionic ligand backbone has been tremendously amplified by shining visible light on it. The catalyst's success relies on its easy access to the one-electron oxidized iminosemiquinonate form that has been thoroughly characterized by X-band electron paramagnetic resonance spectroscopy through spectroelectrochemical experiments. The moderately long-lived excited-state lifetime (10.2 ns) and such a super-reductive ability dependent on the one-electron redox shuttle between the bisamido and iminosemiquinonato forms make this catalysis effective.
Collapse
Affiliation(s)
- Vikramjeet Singh
- Department
of Chemical Sciences, Indian Institute of
Science Education and Research Mohali, SAS Nagar 140306, India
| | - Rahul Singh
- Department
of Chemical Sciences, Indian Institute of
Science Education and Research Mohali, SAS Nagar 140306, India
| | | | - Debashis Adhikari
- Department
of Chemical Sciences, Indian Institute of
Science Education and Research Mohali, SAS Nagar 140306, India
| |
Collapse
|
41
|
Lee B, Pabst TP, Hierlmeier G, Chirik PJ. Exploring the Effect of Pincer Rigidity on Oxidative Addition Reactions with Cobalt(I) Complexes. Organometallics 2023; 42:708-718. [PMID: 37223209 PMCID: PMC10201995 DOI: 10.1021/acs.organomet.3c00079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Abstract
Cobalt complexes containing the 2,6-diaminopyridine-substituted PNP pincer (iPrPNMeNP = 2,6-(iPr2PNMe)2(C5H3N)) were synthesized. A combination of solid-state structures and investigation of the cobalt(I)/(II) redox potential established a relatively rigid and electron-donating chelating ligand as compared to iPrPNP (iPrPNP = 2,6-(iPr2PCH2)2(C5H3N)). Based on a buried volume analysis, the two pincer ligands are sterically indistinguishable. Nearly planar, diamagnetic, four-coordinate complexes were observed independent of the field strength (chloride, alkyl, aryl) of the fourth ligand completing the coordination sphere of the metal. Computational studies supported a higher barrier for C-H oxidative addition, largely a result of the increased rigidity of the pincer. The increased oxidative addition barrier resulted in stabilization of (iPrPNMeNP)Co(I) complexes, enabling the characterization of the cobalt boryl and the cobalt hydride dimer by X-ray crystallography. Moreover, (iPrPNMeNP)CoMe served as an efficient precatalyst for alkene hydroboration likely because of the reduced propensity to undergo oxidative addition, demonstrating that reactivity and catalytic performance can be tuned by rigidity of pincer ligands.
Collapse
Affiliation(s)
- Boran Lee
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Tyler P Pabst
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Gabriele Hierlmeier
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Paul J Chirik
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| |
Collapse
|
42
|
Chu CH, Wang XR, Huang JS, Huang ZM, Li QH, Wang FH. Rare-earth metal complexes supported by indolyl-based NCN-pincer ligand and their efficient catalysis for isoprene polymerization. J Mol Struct 2023. [DOI: 10.1016/j.molstruc.2023.135498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2023]
|
43
|
Hegde V, O SC, Kulkarni NV, Mathew J. Synthesis and Characterization of Cobalt (II) Pincer Complexes and their Application as Dyes in Dye-Sensitized Solar Cells. J Mol Struct 2023. [DOI: 10.1016/j.molstruc.2023.135508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2023]
|
44
|
Cramer HH, Das S, Wodrich MD, Corminboeuf C, Werlé C, Leitner W. Theory-guided development of homogeneous catalysts for the reduction of CO 2 to formate, formaldehyde, and methanol derivatives. Chem Sci 2023; 14:2799-2807. [PMID: 36937594 PMCID: PMC10016328 DOI: 10.1039/d2sc06793e] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 02/09/2023] [Indexed: 02/11/2023] Open
Abstract
The stepwise catalytic reduction of carbon dioxide (CO2) to formic acid, formaldehyde, and methanol opens non-fossil pathways to important platform chemicals. The present article aims at identifying molecular control parameters to steer the selectivity to the three distinct reduction levels using organometallic catalysts of earth-abundant first-row metals. A linear scaling relationship was developed to map the intrinsic reactivity of 3d transition metal pincer complexes to their activity and selectivity in CO2 hydrosilylation. The hydride affinity of the catalysts was used as a descriptor to predict activity/selectivity trends in a composite volcano picture, and the outstanding properties of cobalt complexes bearing bis(phosphino)triazine PNP-type pincer ligands to reach the three reduction levels selectively under different reaction conditions could thus be rationalized. The implications of the composite volcano picture were successfully experimentally validated with selected catalysts, and the challenging intermediate level of formaldehyde could be accessed in over 80% yield with the cobalt complex 6. The results underpin the potential of tandem computational-experimental approaches to propel catalyst design for CO2-based chemical transformations.
Collapse
Affiliation(s)
- Hanna H Cramer
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34-36, 45470 Mülheim an der Ruhr Germany
| | - Shubhajit Das
- Laboratory for Computational Molecular Design Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Matthew D Wodrich
- Laboratory for Computational Molecular Design Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- National Centre for Competence in Research - Catalysis (NCCR-Catalysis), École Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Clémence Corminboeuf
- Laboratory for Computational Molecular Design Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- National Centre for Competence in Research - Catalysis (NCCR-Catalysis), École Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- National Centre for Computational Design and Discovery of Novel Materials (MARVEL), Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
| | - Christophe Werlé
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34-36, 45470 Mülheim an der Ruhr Germany
- Ruhr University Bochum, Universitätsstr. 150 44801 Bochum Germany
| | - Walter Leitner
- Max Planck Institute for Chemical Energy Conversion Stiftstr. 34-36, 45470 Mülheim an der Ruhr Germany
- Institut für Technische und Makromolekulare Chemie (ITMC), RWTH Aachen University Worringer Weg 2 52074 Aachen Germany
| |
Collapse
|
45
|
Elsby MR, Baker RT. Through the Looking Glass: Using the Lens of [SNS]-Pincer Ligands to Examine First-Row Metal Bifunctional Catalysts. Acc Chem Res 2023; 56:798-809. [PMID: 36921212 DOI: 10.1021/acs.accounts.2c00798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
Abstract
ConspectusHomogeneous catalysis is at the forefront of global efforts to innovate the synthesis of fine chemicals and achieve carbon-neutrality in energy applications. For decades, the push toward sustainable catalysis has focused on the development of first-row transition metal catalysts to supplant widespread use of precious metals. Metal-ligand cooperativity is an effective strategy to yield high-performing first-row metal molecular catalysts. Despite remarkable progress, state of the art catalysts often employ phosphorus-based ligands which are air-sensitive, potentially toxic, and on occasion offset the cost-savings of the metal. Thus, the development of simple and economical ligands composed of biomimetic donors should be a key focus that cannot be overlooked in the pursuit of sustainable catalyst candidates. This is an Account of our group's efforts to develop first-row transition metal complexes which use [SNS]-pincer ligands for bifunctional catalysis. We have synthesized two potentially tridentate ligands, one bearing an amido and two thioether donors [(SMeNSMe), L1] and one which includes thiolate, imine, and thioether donors [(SNSMe), L2], and used them as platforms upon which to explore the reaction pathways of first-row metals. The [SNS] ligand, L1, leads to formation of high-spin paramagnetic metal complexes of the type M(L1)2 in which the 6-membered ring thioether donor is hemilabile (M = Mn, Fe, Co). This allows Mn(L1)2 to function as a carbonyl hydroboration catalyst that operates by a novel hydride-free, inner-sphere reaction pathway. Exploring the reactivity of L2 with Fe and Ni revealed unique coordination chemistry and a variety of mono-, di-, tri-, and tetranuclear complexes enabled by bridging thiolates. Further studies showed L2 undergoes selective Caryl-S bond cleavage upon coordination to a metal with electron-rich phosphine donors, yielding a new (CNS)2- pincer ligand. The analogous reaction with L1 afforded a new (CNSMe)- pincer ligand via both Caryl-S and benzylic C-H bond cleavage. In an attempt to prepare Fe(L2)2, we obtained instead an Fe(N2S3) complex in which imine C-C bond formation affords a potentially hexadentate redox-active ligand. The Fe(N2S3) complex is a selective catalyst for hydroboration of aldehydes and appears to operate through a complicated mechanism. In contrast, a mechanistic study of Mn(L2)(CO)3-photocatalyzed dihydroboration of nitriles indicated that both the flexibility of the κ3-SNSMe ligand (fac- vs mer-coordination) and ability of Mn to undergo a spin-state change are required to access low energy barriers for this transformation. To effectively compare the reactivity of the thiolate vs amido donor, we prepared two Cu complexes, Cu(L1)(IPr) and Cu(L2)(IPr) [IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene], showing that, while both served as carbonyl hydroboration catalysts, only the amido complex was an effective catalyst for carbonyl hydrosilylation. In addition, complexes of the type Zn(L1)2, Zn(L2)2, and Zn(L1)(L2), were also effective for catalytic carbonyl hydroboration. While Zn(L1)(L2) was most active, catalyst speciation studies showed that each undergoes bifunctional catalyst activation to form a Zn bis(alkoxide) catalyst. Overall, our observations using [SNS] ligands with first-row transition metals show how the absence of traditional phosphine donors leads to different fundamental reactivity. Furthermore, this Account demonstrates the gap of knowledge which exists in understanding the reactivity of sulfur-based ligands to promote more widespread adoption of sustainable ligands.
Collapse
Affiliation(s)
- Matthew R Elsby
- Department of Chemistry, Yale University, 225 Prospect St, New Haven, Connecticut 06520 United States
| | - R Tom Baker
- Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, 30 Marie Curie, University of Ottawa, Ottawa, ON K1N 6N5 Canada
| |
Collapse
|
46
|
Stadler B, Meng HHY, Belazregue S, Webster L, Collauto A, Byrne KM, Krämer T, Chadwick FM. PCP Pincer Complexes of Titanium in the +3 and +4 Oxidation States. Organometallics 2023. [DOI: 10.1021/acs.organomet.2c00662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2023]
Affiliation(s)
- Benedek Stadler
- Molecular Sciences Research Hub, Department of Chemistry, Imperial College London, 82 Wood Lane, London W12 0BZ, United Kingdom
| | - Hilary H. Y. Meng
- Molecular Sciences Research Hub, Department of Chemistry, Imperial College London, 82 Wood Lane, London W12 0BZ, United Kingdom
| | - Sara Belazregue
- Molecular Sciences Research Hub, Department of Chemistry, Imperial College London, 82 Wood Lane, London W12 0BZ, United Kingdom
| | - Leah Webster
- Molecular Sciences Research Hub, Department of Chemistry, Imperial College London, 82 Wood Lane, London W12 0BZ, United Kingdom
| | - Alberto Collauto
- Molecular Sciences Research Hub, Department of Chemistry, Imperial College London, 82 Wood Lane, London W12 0BZ, United Kingdom
| | - Keelan M. Byrne
- Department of Chemistry, Maynooth University, Maynooth, Co. Kildare W23 F2H6, Ireland
| | - Tobias Krämer
- Department of Chemistry, Maynooth University, Maynooth, Co. Kildare W23 F2H6, Ireland
| | - F. Mark Chadwick
- Molecular Sciences Research Hub, Department of Chemistry, Imperial College London, 82 Wood Lane, London W12 0BZ, United Kingdom
| |
Collapse
|
47
|
Designing a new ligand based on pyridine for immobilization of gold nanoparticles on reduced magnetic graphene oxide: a new catalyst for the reduction of nitro compounds. JOURNAL OF THE IRANIAN CHEMICAL SOCIETY 2023. [DOI: 10.1007/s13738-022-02673-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
48
|
A Brief Review: Advancement in the Synthesis of Amine through the Leuckart Reaction. REACTIONS 2023. [DOI: 10.3390/reactions4010007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
This review presents a summary of reactions that take place during the “Leuckart-type reaction”. The significance of, as well as recent advancements in, the synthesis of amines through simple and inexpensive methods using readily available raw materials is discussed. This review includes all catalytic and noncatalytic reactions that involve the Leuckart method. Recent studies have shown that at least a quarter of C–N bond-forming reactions in the pharmaceutical industry are occur with the support of reductive amination. Recently, experimental conditions have achieved excellent yields. The “Leuckart-type reaction” is technically associated with Eschweiler–Clarke methylation. Compounds are grouped in accordance with the precept of action. This includes drugs affecting the central nervous system, cardiovascular system and gastrointestinal tract; anticancer drugs, antibiotics, antiviral and antifungal drugs; drugs affecting anxiety; convulsant, biotic, and HIV drugs; and antidiabetic drugs. Therefore, this review supports the development of the Leuckart-type preparation of nitrogenous compounds, as well as their advancement in other areas of human development.
Collapse
|
49
|
Ma Y, Hussein AA. Partner effect in accelerating pincer-co catalyzed nitrile hydroboration reactions. Phys Chem Chem Phys 2023; 25:3110-3120. [PMID: 36621824 DOI: 10.1039/d2cp03217a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The pincer-Co catalyzed nitrile hydroboration of nitrile has been presented as an elegant strategy to afford amine synthesis; however, ligand engineering is required. We show here a strategy to tune the catalytic behavior of the organometallic catalyst, as an alternative approach to ligand engineering, by means of computational investigations to understand the effect of partners such as (18-crown-6)K+, W(CO)3 and W(PMe3)3 on the reactivity of the pincer-Co catalyzed nitrile hydroboration reaction through π-coordination to the ligand aromatic ring. The extra additives bind the central phenyl ring of the ligand by either dispersion or chemical bonding. The electron-richness of the cobalt center is tuned by the partner, and follows the order (18-crown-6)K+ > W(PMe3)3 > no partner > W(CO)3. While the influence of the covalent W-containing partners parallels the electron-richness of the W, the non-covalent partner, (18-crown-6)K+, surprisingly increases the donor ability of the pincer ligand through the polarization effect. All the elementary steps involved in the nitrile hydroboration reaction are influenced by the partner, and the overall barrier is lowered by a surprisingly large amount of 4.9 kcal mol-1 in the presence of (18-crown-6)K+, suggesting a notable partner effect to be explored by experimentalists so that the reactivity of a catalyst can be tuned without ligand modification.
Collapse
Affiliation(s)
- Yumiao Ma
- BSJ Institute, Haidian, Beijing, 100084, People's Republic of China.,Hangzhou Yanqu Information Technology Co., Ltd. Xihu District, Hangzhou City, Zhejiang Province, 310003, People's Republic of China.
| | - Aqeel A Hussein
- Department of Medical Laboratory Science, College of Science, Komar University of Science and Technology, 46001 Sulaymaniyah, Kurdistan Region, Iraq.
| |
Collapse
|
50
|
Zhang TS, Fei W, Li N, Zhang Y, Xu C, Luo Q, Li MB. Open Nitrogen Site-Induced Kinetic Resolution and Catalysis of a Gold Nanocluster. NANO LETTERS 2023; 23:235-242. [PMID: 36574348 DOI: 10.1021/acs.nanolett.2c04163] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The emerging metal nanocluster provides a platform for the investigation of structural features, unique properties, and structure-property correlation of nanomaterials at the atomic level. Construction of open sites on the surface of the metal nanocluster is a long-pursued but challenging goal. Herein, we realized the construction of "open organic sites" in a metal nanocluster for the first time. Specifically, we introduce the PNP (2,6-bis(diphenylphosphinomethyl)pyridine) pincer ligand in the synthesis of the gold nanocluster, enabling the construction of a structurally precise Au8(PNP)4 nanocluster. The rigidity and the unique bonding mode of PNP lead to open nitrogen sites on the surface of the Au8(PNP)4 nanocluster, which have been utilized as multifunctional sites in this work for efficient kinetic resolution and catalysis. The gold pincer nanocluster and the open nitrogen site-induced performance will be enlightening for the construction of multifunctional metal nanoclusters.
Collapse
Affiliation(s)
- Tai-Song Zhang
- Institute of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei 230601, P. R. China
| | - Wenwen Fei
- Institute of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei 230601, P. R. China
| | - Na Li
- Institute of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei 230601, P. R. China
| | - Ying Zhang
- Institute of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei 230601, P. R. China
| | - Chang Xu
- School of Chemistry and Chemical Engineering, Anhui University, Hefei 230601, P. R. China
| | - Qiquan Luo
- Institute of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei 230601, P. R. China
| | - Man-Bo Li
- Institute of Physical Science and Information Technology, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Anhui University, Hefei 230601, P. R. China
| |
Collapse
|