1
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Barriendos I, Almárcegui Í, Carmona M, Tejero AG, Soriano-Jarabo A, Blas C, Aguado Z, Carmona D, Lahoz FJ, García-Orduña P, Viguri F, Rodríguez R. Stereocontrol of Metal-Centred Chirality in Rhodium(III) and Ruthenium(II) Complexes with N 2N'P Ligand. Chempluschem 2024:e202400410. [PMID: 38950125 DOI: 10.1002/cplu.202400410] [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: 06/11/2024] [Revised: 06/28/2024] [Accepted: 07/01/2024] [Indexed: 07/03/2024]
Abstract
Rh(III) and Ru(II) complexes, [RhCl2(κ4-N2N'P-L)][SbF6] (1) and [RuCl2(κ4-N2N'P-L)] (2), were synthesised using the tetradentate ligand L (L=N,N-bis[(pyridin-2-yl)methyl]-[2-(diphenylphosphino)phenyl]methanamine). In each case only one diastereomer is detected, featuring cis-disposed pyridine groups. The chloride ligand trans to pyridine can be selectively abstracted by AgSbF6, with the ruthenium complex (2) reacting more readily at room temperature compared to the rhodium complex (1) which requires elevated temperatures. Rhodium complexes avoid the second chloride abstraction, whereas ruthenium complexes can form the chiral bisacetonitrile complex [Ru(κ4-N2N'P-L)(NCMe)2][SbF6]2 (5) upon corresponding treatment with AgSbF6. The complex [RhCl2(κ4-N2N'P-L)][SbF6] (1) has also been used to synthesise polymetallic species, such as the tetrametallic complex [{RhCl2(κ4-N2N'P-L)}2(μ-Ag)2][SbF6]4 (6) which was formed with complete diastereoselectivity and chiral molecular self-recognition. In addition, a stable bimetallic mixed-valence complex [{Rh(κ4-N2N'P-L)}{Rh(COD)}(μ-Cl)2][SbF6]2 (7) (COD=cyclooctadiene) was synthesised. These results highlight the significant differences in chloride lability between Rh3+ and Ru2+ complexes and demonstrate the potential for complexes to act as catalyst precursors and ligands in further chemistry applications.
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Affiliation(s)
- Irati Barriendos
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Íber Almárcegui
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - María Carmona
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Alvaro G Tejero
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Alejandro Soriano-Jarabo
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Carlota Blas
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Zulima Aguado
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009, Zaragoza, Spain
- Universidad San Jorge, Department of Pharmacy, Faculty of Health Sciences, 50830, Villanueva de Gállego (Zaragoza), Spain
| | - Daniel Carmona
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Fernando J Lahoz
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Pilar García-Orduña
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Fernando Viguri
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Ricardo Rodríguez
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009, Zaragoza, Spain
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2
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Tejero AG, Castillo J, Viguri F, Carmona D, Passarelli V, Lahoz FJ, García-Orduña P, Rodríguez R. Dynamic Configuration on a Chiral-at-Rhodium Catalyst Featuring a Flexible Tetradentate Ligand. Chemistry 2024; 30:e202303935. [PMID: 38031971 DOI: 10.1002/chem.202303935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 11/30/2023] [Indexed: 12/01/2023]
Abstract
The unique dynamic configuration of an enantioselective chiral-at-metal catalyst based on Rh(III) and a non-chiral tetradentate ligand is described and resolved. At room temperature, the catalyst undergoes a dynamic configuration process leading to the formation of two interconvertible metal-stereoisomers, remarkably without racemization. Density functional theory (DFT) calculations indicate that this metal-isomerization proceeds via a concerted transition state, which features a trigonal bipyramidal geometry stabilized by the tetradentate ligand. Furthermore, the resolved enantiopure complex shows high catalytic enantioinduction in the Friedel-Crafts reaction, achieving enantiomeric ratios as high as 99 : 1.
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Affiliation(s)
- Alvaro G Tejero
- Departamento de Catálisis y Procesos Catalíticos, Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Javier Castillo
- Departamento de Catálisis y Procesos Catalíticos, Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Fernando Viguri
- Departamento de Catálisis y Procesos Catalíticos, Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Daniel Carmona
- Departamento de Catálisis y Procesos Catalíticos, Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Vincenzo Passarelli
- Departamento de Catálisis y Procesos Catalíticos, Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Fernando J Lahoz
- Departamento de Catálisis y Procesos Catalíticos, Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Pilar García-Orduña
- Departamento de Catálisis y Procesos Catalíticos, Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
| | - Ricardo Rodríguez
- Departamento de Catálisis y Procesos Catalíticos, Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Pedro Cerbuna 12, 50009, Zaragoza, Spain
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3
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Dhimba G, Muller A, Lammertsma K. Chiral-at-Metal Racemization Unraveled for MX 2 (a-chel) 2 by means of a Computational Analysis of MoO 2 (acnac) 2. Chemistry 2023; 29:e202302516. [PMID: 37730887 DOI: 10.1002/chem.202302516] [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: 08/02/2023] [Revised: 09/13/2023] [Accepted: 09/14/2023] [Indexed: 09/22/2023]
Abstract
Octahedral chiral-at-metal complexes MX2 (a-chel)2 (a-chel=asymmetric chelate) can rearrange their ligands by four mechanisms known as the Bailar (B), Ray-Dutt (RD), Conte-Hippler (CH), and Dhimba-Muller-Lammertsma (DML) twists. Racemization involves their interconnections, which were computed for MoO2 (acnac)2 (acnac=β-ketoiminate) using density functional theory at ωB97x-D with the 6-31G(d,p) and 6-311G(2d,p) basis sets and LANL2DZ for molybdenum. Racemizing the cis(NN) isomer, being the global energy minimum with trans oriented imine groups, is a three step process (DML-CH-DML) that requires 17.4 kcal/mol, while all three cis isomers (cis(NN), cis(NO), and cis(OO)) interconvert at ≤17.9 kcal/mol. The B and RD twists are energetically not competitive and neither are the trans isomers. The interconnection of all enantiomeric minima and transition structures is summarized in a graph that also visualizes valley ridge inflection points for two of the three CH twists. Geometrical features of the minima and twists are given. Lastly, the influence of N-substitution on the favored racemization pathway is evaluated. The present comprehensive study serves as a template for designing chiral-at-metal MX2 (a-chel)2 catalysts that may retain their chiral integrity.
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Affiliation(s)
- George Dhimba
- Department of Chemical Sciences, University of Johannesburg, Auckland Park, Johannesburg, 2006, South Africa
| | - Alfred Muller
- Department of Chemical Sciences, University of Johannesburg, Auckland Park, Johannesburg, 2006, South Africa
| | - Koop Lammertsma
- Department of Chemical Sciences, University of Johannesburg, Auckland Park, Johannesburg, 2006, South Africa
- Department of Chemistry and Pharmaceutical Sciences, Faculty of Sciences Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ, Amsterdam, The Netherlands
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4
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Sohtome Y, Komagawa S, Nakamura A, Hashizume D, Lectard S, Akakabe M, Hamashima Y, Uchiyama M, Sodeoka M. Experimental and Computational Investigation of Facial Selectivity Switching in Nickel-Diamine-Acetate-Catalyzed Michael Reactions. J Org Chem 2023. [PMID: 36813263 DOI: 10.1021/acs.joc.2c02732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Chiral Ni complexes have revolutionized both asymmetric acid-base and redox catalysis. However, the coordination isomerism of Ni complexes and their open-shell property still often hinder the elucidation of the origin of their observed stereoselectivity. Here, we report our experimental and computational investigations to clarify the mechanism of β-nitrostyrene facial selectivity switching in Ni(II)-diamine-(OAc)2-catalyzed asymmetric Michael reactions. In the reaction with a dimethyl malonate, the Evans transition state (TS), in which the enolate binds in the same plane with the diamine ligand, is identified as the lowest-energy TS to promote C-C bond formation from the Si face in β-nitrostyrene. In contrast, a detailed survey of the multiple potential pathways in the reaction with α-keto esters points to a clear preference for our proposed C-C bond-forming TS, in which the enolate coordinates to the Ni(II) center in apical-equatorial positions relative to the diamine ligand, thereby promoting Re face addition in β-nitrostyrene. The N-H group plays a key orientational role in minimizing steric repulsion.
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Affiliation(s)
- Yoshihiro Sohtome
- Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.,RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Shinsuke Komagawa
- Elements Chemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Ayako Nakamura
- Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Daisuke Hashizume
- RIKEN Center for Emergent Matter Science, Wako, Saitama 351-0198, Japan
| | - Sylvain Lectard
- Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Mai Akakabe
- Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.,RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Yoshitaka Hamashima
- Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Masanobu Uchiyama
- RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.,Elements Chemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Saitama 351-0198, Japan
| | - Mikiko Sodeoka
- Synthetic Organic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.,RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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5
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Khromova OV, Emelyanov MA, Stoletova NV, Bodunova EE, Prima DO, Smol’yakov AF, Eremenko IL, Maleev VI, Larionov VA. Post-Modification of Octahedral Chiral-at-Metal Cobalt(III) Complexes by Suzuki–Miyaura Cross-Coupling and Evaluation of Their Catalytic Activity. Organometallics 2023. [DOI: 10.1021/acs.organomet.2c00590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Olga V. Khromova
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), Vavilov Str. 28, 119991 Moscow, Russian Federation
| | - Mikhail A. Emelyanov
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), Vavilov Str. 28, 119991 Moscow, Russian Federation
| | - Nadezhda V. Stoletova
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), Vavilov Str. 28, 119991 Moscow, Russian Federation
| | - Ekaterina E. Bodunova
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), Vavilov Str. 28, 119991 Moscow, Russian Federation
- Higher Chemical College of the Russian Academy of Sciences, Miusskaya sq. 9, 125047 Moscow, Russian Federation
| | - Darya O. Prima
- Zelinsky Institute of Organic Chemistry of Russian Academy of Sciences, Leninsky prosp. 47, 119991 Moscow, Russian Federation
| | - Alexander F. Smol’yakov
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), Vavilov Str. 28, 119991 Moscow, Russian Federation
| | - Igor L. Eremenko
- N. S. Kurnakov Institute of General and Inorganic Chemistry of the Russian Academy of Sciences, Leninsky prosp. 31, 119991 Moscow, Russian Federation
| | - Victor I. Maleev
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), Vavilov Str. 28, 119991 Moscow, Russian Federation
| | - Vladimir A. Larionov
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), Vavilov Str. 28, 119991 Moscow, Russian Federation
- Peoples’ Friendship University of Russia (RUDN University), Miklukho-Maklaya Str. 6, 117198 Moscow, Russian Federation
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6
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Tejero AG, Carmona M, Rodríguez R, Viguri F, Lahoz FJ, García-Orduña P, Carmona D. Synthesis of chiral-at-metal rhodium complexes from achiral tripodal tetradentate ligands: resolution and application to enantioselective Diels-Alder and 1,3-dipolar cycloadditions. RSC Adv 2022; 12:34704-34714. [PMID: 36545596 PMCID: PMC9717581 DOI: 10.1039/d2ra06982b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 11/23/2022] [Indexed: 12/04/2022] Open
Abstract
An improved synthesis of the racemic rhodium compound [RhCl2(κ4 C,N,N',P-L1)] (1) containing an achiral tripodal tetradentate ligand is reported. Their derived solvate complexes [Rh(κ4 C,N,N',P-L1)(Solv)2][SbF6]2 (Solv = NCMe, 2; H2O, 3) are resolved into their two enantiomers. Complexes 2 and 3 catalyze the Diels-Alder (DA) reaction between methacrolein and cyclopentadiene and the 1,3-dipolar cycloaddition reaction between methacrolein and the nitrone N-benzylidenphenylamine-N-oxide. When enantiopure (A Rh,R N)-2 was employed as the catalyst, enantiomeric ratios >99/1, in the R at C2 adduct, and up to 94/6, in the 3,5-endo isomer, were achieved in the DA reaction and in the 1,3-dipolar cycloaddition reaction, respectively. A plausible catalytic cycle that accounts for the origin of the observed enantioselectivity is proposed.
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Affiliation(s)
- Alvaro G Tejero
- Departamento de Catálisis y Procesos Catalíticos, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza Pedro Cerbuna 12 50009 Zaragoza Spain
| | - María Carmona
- Departamento de Catálisis y Procesos Catalíticos, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Ricardo Rodríguez
- Departamento de Catálisis y Procesos Catalíticos, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Fernando Viguri
- Departamento de Catálisis y Procesos Catalíticos, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Fernando J Lahoz
- Departamento de Catálisis y Procesos Catalíticos, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Pilar García-Orduña
- Departamento de Catálisis y Procesos Catalíticos, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Daniel Carmona
- Departamento de Catálisis y Procesos Catalíticos, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza Pedro Cerbuna 12 50009 Zaragoza Spain
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7
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Sors-Vendrell A, Ortiz A, Meneses D, Alfonso I, Solà J, Jimeno C. A Degenerate Metal-Templated Catalytic System with Redundant Functional Groups for the Asymmetric Aldol Reaction. J Org Chem 2022; 87:7509-7513. [PMID: 35583468 PMCID: PMC9171831 DOI: 10.1021/acs.joc.2c00414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
![]()
A degenerate zinc-templated
catalytic system containing two bipyridine
ligands with redundant functional groups for either enamine or hydrogen
bond formation was applied to the asymmetric aldol reaction. This
concept led to both a higher probability of reaction and rate acceleration.
Thus, the catalyst loading could be decreased to a remarkable 2 mol
% in what we think is a general approach.
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Affiliation(s)
- Alba Sors-Vendrell
- Department of Biological Chemistry, Institute of Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, Barcelona, Barcelona E08034, Spain
| | - Albert Ortiz
- Department of Biological Chemistry, Institute of Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, Barcelona, Barcelona E08034, Spain
| | - Diego Meneses
- Department of Biological Chemistry, Institute of Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, Barcelona, Barcelona E08034, Spain
| | - Ignacio Alfonso
- Department of Biological Chemistry, Institute of Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, Barcelona, Barcelona E08034, Spain
| | - Jordi Solà
- Department of Biological Chemistry, Institute of Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, Barcelona, Barcelona E08034, Spain
| | - Ciril Jimeno
- Department of Biological Chemistry, Institute of Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, Barcelona, Barcelona E08034, Spain
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8
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Khromova OV, Emelyanov MA, Smol'yakov AF, Fedyanin IV, Maleev VI, Larionov VA. Family of Well-Defined Chiral-at-Cobalt(III) Complexes as Metal-Templated Hydrogen-Bond-Donor Catalysts: Effect of Chirality at the Metal Center on the Stereochemical Outcome of the Reaction. Inorg Chem 2022; 61:5512-5523. [PMID: 35357165 DOI: 10.1021/acs.inorgchem.1c03927] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A family of well-defined Λ- and Δ-diastereomeric octahedral cationic chiral-at-cobalt complexes were obtained by a simple two-step reaction of (R,R)-1,2-diaminocyclohexane, (R,R)-1,2-diphenylethylenediamine, or (S)-2-(aminomethyl)pyrrolidine and substituted salicylaldehydes with a cobalt(III) salt. It was observed for the first time that the use of an excess of cobalt(III) salt provides both the enantiopure Λ and Δ forms of the corresponding cobalt(III) complexes 1 and 2 in a ratio of diastereomers ranging from 1:1.6 to >20:1 (Λ/Δ) and in 31-95% combined yields. The obtained complexes were robust, air- and bench-stable, soluble in most of organic solvents, and insoluble in water. Through variation of the substituents in the phenyl ring of the salicylaldehyde moiety, it was shown that both steric and electronic effects of substituents have a significant impact on the formation of Λ and Δ isomers. Next, the efficacies of the enantiopure metal-templated complexes 1-3 were investigated in three benchmark asymmetric reactions in order to compare their catalytic activity. The chiral cobalt(III) complexes 1-3 were tested as enantioselective hydrogen-bond-donor catalysts in such important reactions as the Michael addition of the O'Donnell substrate to methyl acrylate, epoxidation of chalcone, and trimethylsilylcyanation of benzaldehyde. It was clearly demonstrated that the chirality at the cobalt center has an impact on the stereochemical outcome of the reactions. In particular, the Λ(R,R)-1 and Δ(R,R)-1 complexes acted as "pseudoenantiomeric" catalysts in the epoxidation and trimethylsilylcyanoation reactions, providing both enantiomers of the products with up to 57% enantiomeric excess.
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Affiliation(s)
- Olga V Khromova
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), Vavilov Str. 28, Moscow 119991, Russian Federation
| | - Mikhail A Emelyanov
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), Vavilov Str. 28, Moscow 119991, Russian Federation
| | - Alexander F Smol'yakov
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), Vavilov Str. 28, Moscow 119991, Russian Federation.,Plekhanov Russian University of Economics, Stremyanny per. 36, Moscow 117997, Russian Federation
| | - Ivan V Fedyanin
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), Vavilov Str. 28, Moscow 119991, Russian Federation.,Plekhanov Russian University of Economics, Stremyanny per. 36, Moscow 117997, Russian Federation
| | - Victor I Maleev
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), Vavilov Str. 28, Moscow 119991, Russian Federation
| | - Vladimir A Larionov
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), Vavilov Str. 28, Moscow 119991, Russian Federation.,Peoples' Friendship University of Russia (RUDN University), Miklukho-Maklaya Str. 6, Moscow 117198, Russian Federation
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9
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Wegener AR, Ghosh SK, Bhuvanesh N, Reibenspies J, Gladysz JA. Rhodium(III) Werner Complexes with 1,2‐Diphenylethylenediamine Ligands: Syntheses, Structures, and Applications as Chiral Hydrogen Bond Donor Catalysts and Agents for Enantiomer Purity Determinations. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202200066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Aaron R Wegener
- Texas A&M University Chemistry P.O. Box 30012 77843 College Station UNITED STATES
| | - Subrata K. Ghosh
- Texas A&M University Chemistry P.O. Box 30012 77843 College Station UNITED STATES
| | - Nattamai Bhuvanesh
- Texas A&M University Chemistry P.O. Box 30012 77843 College Station UNITED STATES
| | - Joseph Reibenspies
- Texas A&M University Chemistry P.O. Box 30012 77843 College Station UNITED STATES
| | - John A. Gladysz
- Texas A&M University Department of Chemistry PO Box 30012 77842-3012 College Station UNITED STATES
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10
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Emelyanov MA, Lisov AA, Medvedev MG, Maleev VI, Larionov VA. Cobalt(III) Complexes as Bifunctional Hydrogen Bond Donor Catalysts Featuring Halide Anions for Cyclic Carbonate Synthesis at Ambient Temperature and Pressure: Mechanistic Insight. ASIAN J ORG CHEM 2022. [DOI: 10.1002/ajoc.202100811] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Mikhail A. Emelyanov
- A N Nesmeyanov Institute of Organoelement Compounds RAS: Institut elementoorganiceskih soedinenij imeni A N Nesmeanova RAN LAC Vavilov Str. 28 119991 Moscow RUSSIAN FEDERATION
| | - Alexey A. Lisov
- Lomonosov Moscow State University: Moskovskij gosudarstvennyj universitet imeni M V Lomonosova Chemistry Leninskie Gory 1/3 119991 Moscow RUSSIAN FEDERATION
| | - Michael G. Medvedev
- Zelinsky Institute of Organic Chemistry RAS: Institut organiceskoj himii imeni N D Zelinskogo RAN Chemistry Leninsky prospect 47 119991 Moscow RUSSIAN FEDERATION
| | - Victor I. Maleev
- A N Nesmeyanov Institute of Organoelement Compounds RAS: Institut elementoorganiceskih soedinenij imeni A N Nesmeanova RAN LAC Vavilov Str. 28 119991 Moscow RUSSIAN FEDERATION
| | - Vladimir A. Larionov
- Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences Laboratory of Asymmetric Catalysis Vavilov Street 28 119991 Moscow RUSSIAN FEDERATION
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11
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Dey P, Rai P, Maji B. Recent Development of Bis-Cyclometalated Chiral-at-Iridium and Rhodium Complexes for Asymmetric Catalysis. ACS ORGANIC & INORGANIC AU 2021; 2:99-125. [PMID: 36855455 PMCID: PMC9954445 DOI: 10.1021/acsorginorgau.1c00032] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The field of asymmetric catalysis has been developing to access synthetically efficacious chiral molecules from the last century. Although there are many sustainable ways to produce nonracemic molecules, simplified and unique methodologies are always appreciated. In the recent developments of asymmetric catalysis, chiral-at-metal Lewis acid catalysis has been recognized as an attractive strategy. The catalysts coordinatively activate a substrate while serving the sole source of chirality by virtue of its helical environment. These configurationally stable complexes were utilized in a large number of asymmetric transformations, ranging from asymmetric Lewis acid catalysis to photoredox and electrocatalysis. Here we provide a comprehensive review of the current advancements in asymmetric catalysis utilizing iridium and rhodium-based chiral-at-metal complexes as catalysts. First, the asymmetric transformations via LUMO and HOMO activation assisted by a chiral Lewis acid catalyst are reviewed. In the second part, visible-light-induced asymmetric catalysis is summarized. The asymmetric transformation via the electricity-driven method is discussed in the final section.
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12
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Emelyanov MA, Stoletova NV, Smol'yakov AF, Il'in MM, Maleev VI, Larionov VA. Synthesis and a Catalytic Study of Diastereomeric Cationic Chiral-at-Cobalt Complexes Based on ( R, R)-1,2-Diphenylethylenediamine. Inorg Chem 2021; 60:13960-13967. [PMID: 34449202 DOI: 10.1021/acs.inorgchem.1c00855] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Here we report the first synthesis of two diastereomeric cationic octahedral Co(III) complexes based on commercially available (R,R)-1,2-diphenylethylenediamine and salicylaldehyde. Both diastereoisomers with opposite chiralities at the metal center (Λ and Δ configurations) were prepared. The new Co(III) complexes possessed both acidic hydrogen-bond donating (HBD) NH moieties and nucleophilic counteranions and operate as bifunctional chiral catalysts for the challenging kinetic resolution of terminal and disubstituted epoxides by the reaction with CO2 under mild conditions. The highest selectivity factor (s) of 2.8 for the trans-chalcone epoxide was achieved at low catalyst loading (2 mol %) in chlorobenzene, which is the best achieved result currently for this type of substrate.
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Affiliation(s)
- Mikhail A Emelyanov
- A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Str. 28, 119991 Moscow, Russian Federation
| | - Nadezhda V Stoletova
- A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Str. 28, 119991 Moscow, Russian Federation
| | - Alexander F Smol'yakov
- A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Str. 28, 119991 Moscow, Russian Federation
| | - Mikhail M Il'in
- A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Str. 28, 119991 Moscow, Russian Federation
| | - Victor I Maleev
- A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Str. 28, 119991 Moscow, Russian Federation
| | - Vladimir A Larionov
- A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov Str. 28, 119991 Moscow, Russian Federation.,Peoples' Friendship University of Russia (RUDN University), Miklukho-Maklaya Str. 6, 117198 Moscow, Russian Federation
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13
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Larionov VA, Feringa BL, Belokon YN. Enantioselective "organocatalysis in disguise" by the ligand sphere of chiral metal-templated complexes. Chem Soc Rev 2021; 50:9715-9740. [PMID: 34259242 DOI: 10.1039/d0cs00806k] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Asymmetric catalysis holds a prominent position among the important developments in chemistry during the 20th century. This was acknowledged by the 2001 Nobel Prize in chemistry awarded to Knowles, Noyori, and Sharpless for their development of chiral metal catalysts for organic transformations. The key feature of the catalysts was the crucial role of the chiral ligand and the nature of the metal ions, which promoted the catalytic conversions of the substrates via direct coordination. Subsequently the development of asymmetric organic catalysis opened new avenues to the synthesis of enantiopure compounds, avoiding any use of metal ions. Recently, an alternative approach to asymmetric catalysis emerged that relied on the catalytic functions of the ligands themselves boosted by coordination to metal ions. In other words, in these hybrid chiral catalysts the substrates are activated not by the metal ions but by the ligands. The activation and enantioselective control occurred via well-orchestrated and custom-tailored non-covalent interactions of the substrates with the ligand sphere of chiral metal complexes. In these metal-templated catalysts, the metal served either as a template (a purely structural role), or it constituted the exclusive source of chirality (metal-centred chirality due to the spatial arrangement of achiral or chiral bi-/tridentate ligands around an octahedral metal centre), and/or it increased the Brønsted acidity of the ligands. Although the field is still in its infancy, it represents an inspiring combination of both metal and organic catalysis and holds major unexplored potential to push the frontiers of asymmetric catalysis. Here we present an overview of this emerging field discussing the principles, applications and perspectives on the catalytic use of chiral metal complexes that operate as "organocatalysts in disguise". It has been demonstrated that these chiral metal complexes are efficient and provide high stereoselective control in asymmetric hydrogen bonding catalysis, phase-transfer catalysis, Brønsted acid/base catalysis, enamine catalysis, nucleophilic catalysis, and photocatalysis as well as bifunctional catalysis. Also, many of the catalysts have been identified as highly effective catalysts at remarkably low catalyst loadings. These hybrid systems offer many opportunities in the synthesis of chiral compounds and represent promising alternatives to metal-based and organocatalytic asymmetric transformations.
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Affiliation(s)
- Vladimir A Larionov
- A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, Vavilov Street 28, 119991 Moscow, Russian Federation.
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14
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Kabes CQ, Lucas RF, Gunn JH, Gladysz JA. Chiral Cobalt(III) Tris(1,2-diamine) Catalysts That Incorporate Nitrogenous Base Containing Anions for the Bifunctional Activation of Nucleophiles and Electrophiles in Enantioselective Addition Reactions. ACS Catal 2021. [DOI: 10.1021/acscatal.1c01883] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Connor Q. Kabes
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - Reagan F. Lucas
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - Jack H. Gunn
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - John A. Gladysz
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
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15
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Expanding the Family of Octahedral Chiral-at-Metal Cobalt(III) Catalysts by Introducing Tertiary Amine Moiety into the Ligand. Catalysts 2021. [DOI: 10.3390/catal11020152] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Chiral metal-templated complexes are attractive catalysts for organic synthetic transformations. Herein, we introduce a novel chiral cobalt(III)-templated complex based on chiral trans-3,4-diamino-1-benzylpyrrolidine and 3,5-di-tert-butyl-salicylaldehyde which features both hydrogen bond donor and Brønsted base functionalities. The obtained complexes were fully characterized by 1H, 13C NMR, IR-, UV-vis, CD-spectroscopy and by a single X-ray diffraction analysis. It was shown that chlorine anion is connected with amino groups of the complex via a hydrogen bonding. DFT calculations of charges and molecular electrostatic potential of the cobalt(III) complex showed that the basicity of the complex is certainly diminished as compared with the routine tertiary amines but the acidity of the conjugated acid of the complex should be increased. Thus, the catalytic potential of the complex may be much greater as a chiral acid than a chiral base. We believe that this work opens a new way in chiral bifunctional catalyst design.
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16
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Emelyanov MA, Stoletova NV, Lisov AA, Medvedev MG, Smol'yakov AF, Maleev VI, Larionov VA. An octahedral cobalt(iii) complex based on cheap 1,2-phenylenediamine as a bifunctional metal-templated hydrogen bond donor catalyst for fixation of CO2 with epoxides under ambient conditions. Inorg Chem Front 2021. [DOI: 10.1039/d1qi00464f] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
An octahedral cobalt(iii) complex based on cheap 1,2-phenylenediamine operates as an efficient bifunctional hydrogen bond donor catalyst in cycloaddition of epoxides with CO2 under ambient conditions and solvent- and co-catalyst-free conditions.
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Affiliation(s)
- Mikhail A. Emelyanov
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS)
- 119991 Moscow
- Russian Federation
| | - Nadezhda V. Stoletova
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS)
- 119991 Moscow
- Russian Federation
| | - Alexey A. Lisov
- Department of Chemistry
- Lomonosov Moscow State University
- 119991 Moscow
- Russian Federation
- N.D. Zelinsky Institute of Organic Chemistry of Russian Academy of Sciences
| | - Michael G. Medvedev
- N.D. Zelinsky Institute of Organic Chemistry of Russian Academy of Sciences
- 119991 Moscow
- Russian Federation
| | - Alexander F. Smol'yakov
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS)
- 119991 Moscow
- Russian Federation
| | - Victor I. Maleev
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS)
- 119991 Moscow
- Russian Federation
| | - Vladimir A. Larionov
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS)
- 119991 Moscow
- Russian Federation
- Peoples’ Friendship University of Russia (RUDN University)
- 117198 Moscow
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17
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Asymmetric construction of tetrahedral chiral zinc with high configurational stability and catalytic activity. Nat Commun 2020; 11:6263. [PMID: 33298960 PMCID: PMC7726038 DOI: 10.1038/s41467-020-20074-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 11/12/2020] [Indexed: 12/13/2022] Open
Abstract
Chiral metal complexes show promise as asymmetric catalysts and optical materials. Chiral-at-metal complexes composed of achiral ligands have expanded the versatility and applicability of chiral metal complexes, especially for octahedral and half-sandwich complexes. However, Werner-type tetrahedral complexes with a stereogenic metal centre are rarely used as chiral-at-metal complexes because they are too labile to ensure the absolute configuration of the metal centre. Here we report the asymmetric construction of a tetrahedral chiral-at-zinc complex with high configurational stability, using an unsymmetric tridentate ligand. Coordination/substitution of a chiral auxiliary ligand on zinc followed by crystallisation yields an enantiopure chiral-only-at-zinc complex (> 99% ee). The enantiomer excess remains very high at 99% ee even after heating at 70 °C in benzene for one week. With this configurationally stable zinc complex of the tridentate ligand, the remaining one labile site on the zinc can be used for a highly selective asymmetric oxa-Diels-Alder reaction (98% yield, 87% ee) without substantial racemisation.
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18
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Wegener AR, Kabes CQ, Gladysz JA. Launching Werner Complexes into the Modern Era of Catalytic Enantioselective Organic Synthesis. Acc Chem Res 2020; 53:2299-2313. [PMID: 32886471 DOI: 10.1021/acs.accounts.0c00410] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Reactions catalyzed by transition metal complexes almost always entail binding of one or more reactants to the metal center, and nearly every corner of the "chiral pool" has been picked over in efforts to develop enantioselective catalysts. As reported by Alfred Werner in 1911-1912, salts of the formally D3-symmetric [Co(en)3]3+ trication (en = ethylenediamine) were among the first chiral inorganic compounds to be resolved into enantiomers. These air- and water-stable complexes are substitution-inert, so for 100 years they languished without application in organic synthesis. We then showed that when they are rendered soluble in organic media by lipophilic anions such as fluorinated tetraarylborates BArf-, they become potent catalysts for a variety of carbon-carbon and carbon-heteroatom bond forming reactions.These involve substrate activation by hydrogen bonding to the coordinated NH2 units (pKa ca. 15), a "second coordination sphere" mechanism. Only modest enantioselectivities are obtained with [Co(en)3]3+ 3BArf- or related chromium, rhodium, iridium, and platinum salts. However, high enantioselectivities are achieved when the three en ligands are replaced by the 1,2-diphenyl analogues (S,S)- or (R,R)-H2NCHPhCHPhNH2. Here only one BArf- anion is required to solubilize the trication, so a number of mixed-salt catalysts (2X-BArf-) have been evaluated. Alternatively, a dimethylamino group can be tethered to the backbone of one en ligand, providing bifunctional catalysts that obviate any need for an external base. Interestingly, the counteranions modulate the enantioselectivities somewhat. However, catalysts with chiral anions do not significantly outperform benchmark catalysts with achiral anions. Cagelike chiral hexaaminecobalt(III) complexes known as sepulchrates and sarcophagines, which feature secondary NH donor atoms, can also serve as catalysts, but the enantioselectivities are very low.In a spinoff application, certain salts are found to be superb "chiral solvating agents", leading to distinct sets of NMR signals for enantiomers of chiral analytes with Lewis basic functional groups. Loadings of 10-25 mol % generally suffice, providing the best way of assaying the enantiomeric purities of a host of compounds. Also, mixtures of several chiral compounds can be simultaneously analyzed. It is not surprising that complexes that perform well in chiral recognition phenomena also excel as enantioselective catalysts.In this Account, the stereochemical properties of the preceding complexes are treated, as well as arcana generally known only to specialists in the field. These include the use of charcoal for equilibrating configurations of the cobalt stereocenter and Sephadex for separating enantiomers and diastereomers. Other types of metal-containing hydrogen-bond-donor catalysts are briefly surveyed (noncoordinating NH units can also be effective), including several developed by other groups. However, the mechanisms of enantioselection in all of these transformations remain obscure. The optimum diastereomer and anion set varies from reaction to reaction, suggesting a "phenotypic plasticity" that allows adaption to a variety of processes.
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Affiliation(s)
- Aaron R. Wegener
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - Connor Q. Kabes
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - John A. Gladysz
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
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19
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Fanourakis A, Docherty PJ, Chuentragool P, Phipps RJ. Recent Developments in Enantioselective Transition Metal Catalysis Featuring Attractive Noncovalent Interactions between Ligand and Substrate. ACS Catal 2020; 10:10672-10714. [PMID: 32983588 PMCID: PMC7507755 DOI: 10.1021/acscatal.0c02957] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 08/14/2020] [Indexed: 12/11/2022]
Abstract
Enantioselective transition metal catalysis is an area very much at the forefront of contemporary synthetic research. The development of processes that enable the efficient synthesis of enantiopure compounds is of unquestionable importance to chemists working within the many diverse fields of the central science. Traditional approaches to solving this challenge have typically relied on leveraging repulsive steric interactions between chiral ligands and substrates in order to raise the energy of one of the diastereomeric transition states over the other. By contrast, this Review examines an alternative tactic in which a set of attractive noncovalent interactions operating between transition metal ligands and substrates are used to control enantioselectivity. Examples where this creative approach has been successfully applied to render fundamental synthetic processes enantioselective are presented and discussed. In many of the cases examined, the ligand scaffold has been carefully designed to accommodate these attractive interactions, while in others, the importance of the critical interactions was only elucidated in subsequent computational and mechanistic studies. Through an exploration and discussion of recent reports encompassing a wide range of reaction classes, we hope to inspire synthetic chemists to continue to develop asymmetric transformations based on this powerful concept.
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Affiliation(s)
- Alexander Fanourakis
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Philip J. Docherty
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Padon Chuentragool
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Robert J. Phipps
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
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20
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Luu QH, Gladysz JA. An Air‐ and Water‐Stable Hydrogen‐Bond‐Donor Catalyst for the Enantioselective Generation of Quaternary Carbon Stereocenters by Additions of Substituted Cyanoacetate Esters to Acetylenic Esters. Chemistry 2020; 26:10230-10239. [DOI: 10.1002/chem.202001639] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 05/12/2020] [Indexed: 11/05/2022]
Affiliation(s)
- Quang H. Luu
- Department of Chemistry Texas A&M University P.O. Box 30012 College Station Texas 77842-3012 USA
| | - John A. Gladysz
- Department of Chemistry Texas A&M University P.O. Box 30012 College Station Texas 77842-3012 USA
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21
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Mukherjee T, Ghosh SK, Wititsuwannakul T, Bhuvanesh N, Gladysz JA. Chiral-at-Metal Ruthenium Complexes with Guanidinobenzimidazole and Pentaphenylcyclopentadienyl Ligands: Synthesis, Resolution, and Preliminary Screening as Enantioselective Second Coordination Sphere Hydrogen Bond Donor Catalysts. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00073] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Tathagata Mukherjee
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77843-3012, United States
| | - Subrata K. Ghosh
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77843-3012, United States
| | - Taveechai Wititsuwannakul
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77843-3012, United States
| | - Nattamai Bhuvanesh
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77843-3012, United States
| | - John A. Gladysz
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77843-3012, United States
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22
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Wititsuwannakul T, Mukherjee T, Hall MB, Gladysz JA. Computational Investigations of Enantioselection in Carbon–Carbon Bond Forming Reactions of Ruthenium Guanidinobenzimidazole Second Coordination Sphere Hydrogen Bond Donor Catalysts. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00072] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Taveechai Wititsuwannakul
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77843-3012, United States
| | - Tathagata Mukherjee
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77843-3012, United States
| | - Michael B. Hall
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77843-3012, United States
| | - John A. Gladysz
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77843-3012, United States
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23
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Maximuck WJ, Ganzmann C, Alvi S, Hooda KR, Gladysz JA. Rendering classical hydrophilic enantiopure Werner salts [M(en) 3] n+nX - lipophilic (M/n = Cr/3, Co/3, Rh/3, Ir/3, Pt/4); new chiral hydrogen bond donor catalysts and enantioselectivities as a function of metal and charge. Dalton Trans 2020; 49:3680-3691. [PMID: 32124905 DOI: 10.1039/d0dt00523a] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Known hydrophilic halide salts of the title compounds are converted to new lipophilic BArf- (B(3,5-C6H3(CF3)2)4-) salts. These are isolated as hydrates (Λ- or Δ-[M(en)3]n+nBArf-·zH2O; z = 17-9) and characterized by NMR (acetone-d6) and microanalyses. Thermal stabilities are probed by capillary thermolyses and TGA and DSC measurements (onset of dehydration 71-151 °C). In the presence of tertiary amines, they are effective catalysts for enantioselective Michael type carbon-carbon or carbon-nitrogen bond forming additions of 1,3-dicarbonyl compounds (acceptors: trans-β-nitrostyrene, di-tert-butylazodicarboxylate, 2-cyclopenten-1-one; average ee = 33%, 52%, 17%). Effects of the metal and charge upon enantioselectivities are analyzed. A number of properties appear to correlate to the NH Brønsted acidity order ([Pt(en)3]4+ > [Cr(en)3]3+ > [Co(en)3]3+ > [Rh(en)3]3+ > [Ir(en)3]3+).
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Affiliation(s)
- William J Maximuck
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, USA.
| | - Carola Ganzmann
- Institut für Organische Chemie and Interdisciplinary Center for Molecular Materials Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestraße 42, 91054 Erlangen, Germany
| | - Scheherzad Alvi
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, USA.
| | - Karan R Hooda
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, USA.
| | - John A Gladysz
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, USA.
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24
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Kabes CQ, Maximuck WJ, Ghosh SK, Kumar A, Bhuvanesh N, Gladysz JA. Chiral Tricationic Tris(1,2-diphenylethylenediamine) Cobalt(III) Hydrogen Bond Donor Catalysts with Defined Carbon/Metal Configurations; Matched/Mismatched Effects upon Enantioselectivities with Enantiomeric Chiral Counter Anions. ACS Catal 2020. [DOI: 10.1021/acscatal.9b05496] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Connor Q. Kabes
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - William J. Maximuck
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - Subrata K. Ghosh
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - Anil Kumar
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - Nattamai Bhuvanesh
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - John A. Gladysz
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
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25
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Gimeno MC, Herrera RP. Hydrogen Bonding and Internal or External Lewis or Brønsted Acid Assisted (Thio)urea Catalysts. European J Org Chem 2019. [DOI: 10.1002/ejoc.201901344] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- M. Concepción Gimeno
- Departamento de Química Inorgánica; Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) CSIC-Universidad de Zaragoza; C/ Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Raquel P. Herrera
- Departamento de Química Orgánica. Laboratorio de Organocatálisis Asimétrica; Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) CSIC-Universidad de Zaragoza; C/ Pedro Cerbuna 12 50009 Zaragoza Spain
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26
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Maximuck WJ, Gladysz JA. Lipophilic chiral cobalt (III) complexes of hexaamine ligands: Efficacies as enantioselective hydrogen bond donor catalysts. MOLECULAR CATALYSIS 2019. [DOI: 10.1016/j.mcat.2019.03.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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27
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De los Santos ZA, Lynch CC, Wolf C. Optische Chiralitätssensorik mit ligandenfreien, weit verbreiteten Cobaltsalzen. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201811761] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Zeus A. De los Santos
- Department of Chemistry Georgetown University 37th and O Streets Washington DC 20057 USA
| | - Ciarán C. Lynch
- Department of Chemistry Georgetown University 37th and O Streets Washington DC 20057 USA
| | - Christian Wolf
- Department of Chemistry Georgetown University 37th and O Streets Washington DC 20057 USA
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28
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De los Santos ZA, Lynch CC, Wolf C. Optical Chirality Sensing with an Auxiliary‐Free Earth‐Abundant Cobalt Probe. Angew Chem Int Ed Engl 2018; 58:1198-1202. [DOI: 10.1002/anie.201811761] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 11/20/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Zeus A. De los Santos
- Department of Chemistry Georgetown University 37th and O Streets Washington DC 20057 USA
| | - Ciarán C. Lynch
- Department of Chemistry Georgetown University 37th and O Streets Washington DC 20057 USA
| | - Christian Wolf
- Department of Chemistry Georgetown University 37th and O Streets Washington DC 20057 USA
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29
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Cruchter T, Larionov VA. Asymmetric catalysis with octahedral stereogenic-at-metal complexes featuring chiral ligands. Coord Chem Rev 2018. [DOI: 10.1016/j.ccr.2018.08.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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30
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Grommet AB, Hoffman JB, Percástegui EG, Mosquera J, Howe DJ, Bolliger JL, Nitschke JR. Anion Exchange Drives Reversible Phase Transfer of Coordination Cages and Their Cargoes. J Am Chem Soc 2018; 140:14770-14776. [DOI: 10.1021/jacs.8b07900] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Angela B. Grommet
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Jack B. Hoffman
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Edmundo G. Percástegui
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Jesús Mosquera
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Duncan J. Howe
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Jeanne L. Bolliger
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
| | - Jonathan R. Nitschke
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
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31
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Zheng K, Liu X, Feng X. Recent Advances in Metal-Catalyzed Asymmetric 1,4-Conjugate Addition (ACA) of Nonorganometallic Nucleophiles. Chem Rev 2018; 118:7586-7656. [PMID: 30047721 DOI: 10.1021/acs.chemrev.7b00692] [Citation(s) in RCA: 191] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The metal-catalyzed asymmetric conjugate addition (ACA) reaction has emerged as a general and powerful approach for the construction of optically active compounds and is among the most significant and useful reactions in synthetic organic chemistry. In recent years, great progress has been made in this area with the use of various chiral metal complexes based on different chiral ligands. This review provides comprehensive and critical information on the enantioselective 1,4-conjugate addition of nonorganometallic (soft) nucleophiles and their importance in synthetic applications. The literature is covered from the last 10 years, and a number of examples from before 2007 are included as background information. The review is divided into multiple parts according to the type of nucleophile involved in the reaction (such as C-, B-, O-, N-, S-, P-, and Si-centered nucleophiles) and metal catalyst systems used.
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Affiliation(s)
- Ke Zheng
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry , Sichuan University , Chengdu 610064 , P. R. China
| | - Xiaohua Liu
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry , Sichuan University , Chengdu 610064 , P. R. China
| | - Xiaoming Feng
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry , Sichuan University , Chengdu 610064 , P. R. China
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32
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Luu QH, Lewis KG, Banerjee A, Bhuvanesh N, Gladysz JA. The robust, readily available cobalt(iii) trication [Co(NH 2CHPhCHPhNH 2) 3] 3+ is a progenitor of broadly applicable chirality and prochirality sensing agents. Chem Sci 2018; 9:5087-5099. [PMID: 29938040 PMCID: PMC5994889 DOI: 10.1039/c8sc01510d] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 05/09/2018] [Indexed: 12/16/2022] Open
Abstract
When NMR spectra of chiral racemic organic molecules containing a Lewis basic functional group are recorded in the presence of air and water stable salts of the cobalt(iii) trication [Co((S,S)-NH2CHPhCHPhNH2)3]3+ (23+), separate signals are usually observed for the enantiomers (28 diverse examples, >12 functional groups). Several chiral molecules can be simultaneously analyzed, and enantiotopic groups in prochiral molecules differentiated (16 examples). Particularly effective are the mixed bis(halide)/tetraarylborate salts Λ-23+ 2X-BArf- (X = Cl, I; BArf = B(3,5-C6H3(CF3)2)4), which are applied in CD2Cl2 or CDCl3 at 1-100 mol% (avg 34 and 14 mol%). Job plots establish 1 : 1 binding for Λ-23+ 2Cl-BArf- and 1-phenylethyl acetate (4) or 1-phenylethanol (10), and ca. 1 : 2 binding with DMSO (CD2Cl2). Selected binding constants are determined, which range from 7.60-2.73 M-1 for the enantiomers of 10 to 28.1-22.6 M-1 for the enantiomers of 4. The NH moieties of the C2 faces of the trication are believed to hydrogen bond to the Lewis basic functional groups, as seen in the crystal structure of a hexakis(DMSO) solvate of Λ-23+ 3I-. These salts rank with the most broadly applicable chirality sensing agents discovered to date.
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Affiliation(s)
- Quang H Luu
- Department of Chemistry , Texas A&M University , P.O. Box 30012 , College Station , Texas 77842-3012 , USA .
| | - Kyle G Lewis
- Department of Chemistry , Texas A&M University , P.O. Box 30012 , College Station , Texas 77842-3012 , USA .
| | - Anik Banerjee
- Department of Chemistry , Texas A&M University , P.O. Box 30012 , College Station , Texas 77842-3012 , USA .
| | - Nattamai Bhuvanesh
- Department of Chemistry , Texas A&M University , P.O. Box 30012 , College Station , Texas 77842-3012 , USA .
| | - John A Gladysz
- Department of Chemistry , Texas A&M University , P.O. Box 30012 , College Station , Texas 77842-3012 , USA .
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33
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Serra-Pont A, Alfonso I, Solà J, Jimeno C. A copper-templated, bifunctional organocatalyst: a strongly cooperative dynamic system for the aldol reaction. Org Biomol Chem 2018; 15:6584-6591. [PMID: 28749514 DOI: 10.1039/c7ob01370a] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The study of novel metal-templated dynamic organocatalytic systems has led to the identification of CuSO4 as the most efficient template to assemble monofunctional prolinamide- and thiourea-modified pyridine ligands. The structural and electronic requirements to assemble an efficient catalyst have been disclosed: both pyridine ligands must bear a 1,3-substitution pattern, and the thiourea ligand serves as a reducing agent to copper(i) as well. Eventually, the cooperative effects achieved with such a simple system deliver high reaction rates and stereoselectivities at room temperature in the asymmetric aldol reaction, requiring only 1 mol% of copper salt.
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Affiliation(s)
- Anna Serra-Pont
- Department of Biological Chemistry and Molecular Modelling, Institute of Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, E08034 Barcelona, Spain.
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34
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Hydrogen bonding motifs in structurally characterized salts of the tris(ethylenediamine) cobalt trication, [Co(en)3]3+; An interpretive review, including implications for catalysis. Coord Chem Rev 2017. [DOI: 10.1016/j.ccr.2017.04.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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35
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Zhang L, Meggers E. Stereogenic-Only-at-Metal Asymmetric Catalysts. Chem Asian J 2017; 12:2335-2342. [PMID: 28782915 DOI: 10.1002/asia.201700739] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 07/06/2017] [Indexed: 11/10/2022]
Abstract
Chirality is an essential feature of asymmetric catalysts. This review summarizes asymmetric catalysts that derive their chirality exclusively from stereogenic metal centers. Reported chiral-at-metal catalysts can be divided into two classes, namely, inert metal complexes, in which the metal fulfills a purely structural role, so catalysis is mediated entirely through the ligand sphere, and reactive metal complexes. The latter are particularly appealing because structural simplicity (only achiral ligands) is combined with the prospect of particularly effective asymmetric induction (direct contact of the substrate with the chiral metal center). Challenges and solutions for the design of such reactive stereogenic-only-at-metal asymmetric catalysts are discussed.
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Affiliation(s)
- Lilu Zhang
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043, Marburg, Germany
| | - Eric Meggers
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043, Marburg, Germany
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36
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Cruchter T, Medvedev MG, Shen X, Mietke T, Harms K, Marsch M, Meggers E. Asymmetric Nucleophilic Catalysis with an Octahedral Chiral-at-Metal Iridium(III) Complex. ACS Catal 2017. [DOI: 10.1021/acscatal.7b01296] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Thomas Cruchter
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Michael G. Medvedev
- X-ray
Structural Laboratory, A.N. Nesmeyanov Institute of Organoelement Compounds RAS, Vavilova St. 28, 119991 Moscow, Russian Federation
- N.D. Zelinsky Institute of Organic Chemistry RAS, Leninsky Prospect 47, 119991 Moscow, Russian Federation
| | - Xiaodong Shen
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Thomas Mietke
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Klaus Harms
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Michael Marsch
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Eric Meggers
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
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37
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Meggers E. Ausnutzung oktaedrischer Stereozentren: von Enzymhemmung bis hin zu asymmetrischer Photoredoxkatalyse. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201612516] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Eric Meggers
- Fachbereich Chemie; Philipps-Universität Marburg; Hans-Meerwein-Straße 4 35043 Marburg Deutschland
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38
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Meggers E. Exploiting Octahedral Stereocenters: From Enzyme Inhibition to Asymmetric Photoredox Catalysis. Angew Chem Int Ed Engl 2017; 56:5668-5675. [DOI: 10.1002/anie.201612516] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Indexed: 12/21/2022]
Affiliation(s)
- Eric Meggers
- Fachbereich Chemie, Philipps-Universität Marburg; Hans-Meerwein-Strasse 4 35043 Marburg Germany
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39
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Octahedral Ruthenium Complex with Exclusive Metal-Centered Chirality for Highly Effective Asymmetric Catalysis. J Am Chem Soc 2017; 139:4322-4325. [PMID: 28290685 DOI: 10.1021/jacs.7b01098] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A novel ruthenium catalyst is introduced which contains solely achiral ligands and acquires its chirality entirely from octahedral centrochirality. The configurationally stable catalyst is demonstrated to catalyze the alkynylation of trifluoromethyl ketones with very high enantioselectivity (up to >99% ee) at low catalyst loadings (down to 0.2 mol%).
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40
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Zhang L, Meggers E. Steering Asymmetric Lewis Acid Catalysis Exclusively with Octahedral Metal-Centered Chirality. Acc Chem Res 2017; 50:320-330. [PMID: 28128920 DOI: 10.1021/acs.accounts.6b00586] [Citation(s) in RCA: 233] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Catalysts for asymmetric synthesis must be chiral. Metal-based asymmetric catalysts are typically constructed by assembling chiral ligands around a central metal. In this Account, a new class of effective chiral Lewis acid catalysts is introduced in which the octahedral metal center constitutes the exclusive source of chirality. Specifically, the here discussed class of catalysts are composed of configurationally stable, chiral-at-metal Λ-configured (left-handed propeller) or Δ-configured (right-handed propeller) iridium(III) or rhodium(III) complexes containing two bidentate cyclometalating 5-tert-butyl-2-phenylbenzoxazole (dubbed IrO and RhO) or 5-tert-butyl-2-phenylbenzothiazole (dubbed IrS and RhS) ligands in addition to two exchange-labile acetonitriles. They are synthetically accessible in an enantiomerically pure fashion through a convenient auxiliary-mediated synthesis. Such catalysts are of interest due to their intrinsic structural simplicity (only achiral ligands) and the prospect of an especially effective asymmetric induction due to the intimate contact between the chiral metal center and the metal-coordinated substrates or reagents. With respect to chiral Lewis acid catalysis, the bis-cyclometalated iridium and rhodium complexes provide excellent catalytic activities and asymmetric inductions for a variety of reactions including Michael additions, Friedel-Crafts reactions, cycloadditions, α-aminations, α-fluorinations, Mannich reactions, and a cross-dehydrogenative coupling. Mechanistically, substrates such as 2-acyl imidazoles are usually activated by two-point binding. Exceptions exist as for example for an efficient iridium-catalyzed enantioselective transfer hydrogenation of arylketones with ammonium formate, which putatively proceeds through an iridium-hydride intermediate. The bis-cyclometalated iridium complexes catalyze visible-light-induced asymmetric reactions by intertwining asymmetric catalysis and photoredox catalysis in a unique fashion. This has been applied to the visible-light-induced α-alkylation of 2-acyl imidazoles (and in some instances 2-acylpyridines) with acceptor-substituted benzyl, phenacyl, trifluoromethyl, perfluoroalkyl, and trichloromethyl groups, in addition to photoinduced oxidative α-aminoalkylations and a photoinduced stereocontrolled radical-radical coupling, each employing a single iridium complex. In all photoinduced reaction schemes, the iridium complex serves as a chiral Lewis acid catalyst and at the same time as precursor of in situ assembled photoactive species. The nature of these photoactive intermediates then determines their photochemical properties and thereby the course of the asymmetric photoredox reactions. The bis-cyclometalated rhodium complexes are also very useful for asymmetric photoredox catalysis. Less efficient photochemical properties are compensated with a more rapid ligand exchange kinetics, which permits higher turnover frequencies of the catalytic cycle. This has been applied to a visible-light-induced enantioselective radical α-amination of 2-acyl imidazoles. In this reaction, an intermediate rhodium enolate is supposed to function as a photoactivatable smart initiator to initiate and reinitiate an efficient radical chain process. If a more efficient photoactivation is required, a rhodium-based Lewis acid can be complemented with a photoredox cocatalyst, and this has been applied to efficient catalytic asymmetric alkyl radical additions to acceptor-substituted alkenes. We believe that this class of chiral-only-at-metal Lewis acid catalysts will be of significant value in the field of asymmetric synthesis, in particular in combination with visible-light-induced redox chemistry, which has already resulted in novel strategies for asymmetric synthesis of chiral molecules. Hopefully, this work will also pave the way for the development of other asymmetric catalysts featuring exclusively octahedral centrochirality.
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Affiliation(s)
- Lilu Zhang
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Eric Meggers
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
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41
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Ghosh SK, Lewis KG, Kumar A, Gladysz JA. Syntheses of Families of Enantiopure and Diastereopure Cobalt Catalysts Derived from Trications of the Formula [Co(NH2CHArCHArNH2)3]3+. Inorg Chem 2017; 56:2304-2320. [DOI: 10.1021/acs.inorgchem.6b03042] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Subrata K. Ghosh
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - Kyle G. Lewis
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - Anil Kumar
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - John A. Gladysz
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
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42
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Hao XQ, Wang C, Liu SL, Wang X, Wang L, Gong JF, Song MP. Cobalt(ii)/(imidazoline–oxazoline)-catalyzed enantioselective Michael addition of 2-acetyl azaarenes to β-CF3-β-disubstituted nitroalkenes. Org Chem Front 2017. [DOI: 10.1039/c6qo00562d] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Cobalt(ii)/(imidazoline–oxazoline)-catalyzed enantioselective Michael addition of 2-acetyl azaarenes to β-CF3-β-disubstituted nitroalkenes is reported, providing chiral compounds with an all-carbon quaternary stereocenter in high yields and excellent enantioselectivities.
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Affiliation(s)
- Xin-Qi Hao
- College of Chemistry and Molecular Engineering
- Henan Key Laboratory of Chemical Biology and Organic Chemistry
- Zhengzhou University
- Zhengzhou 450001
- People's Republic of China
| | - Cong Wang
- College of Chemistry and Molecular Engineering
- Henan Key Laboratory of Chemical Biology and Organic Chemistry
- Zhengzhou University
- Zhengzhou 450001
- People's Republic of China
| | - Shuang-Liang Liu
- College of Chemistry and Molecular Engineering
- Henan Key Laboratory of Chemical Biology and Organic Chemistry
- Zhengzhou University
- Zhengzhou 450001
- People's Republic of China
| | - Xiao Wang
- College of Chemistry and Molecular Engineering
- Henan Key Laboratory of Chemical Biology and Organic Chemistry
- Zhengzhou University
- Zhengzhou 450001
- People's Republic of China
| | - Li Wang
- College of Chemistry and Molecular Engineering
- Henan Key Laboratory of Chemical Biology and Organic Chemistry
- Zhengzhou University
- Zhengzhou 450001
- People's Republic of China
| | - Jun-Fang Gong
- College of Chemistry and Molecular Engineering
- Henan Key Laboratory of Chemical Biology and Organic Chemistry
- Zhengzhou University
- Zhengzhou 450001
- People's Republic of China
| | - Mao-Ping Song
- College of Chemistry and Molecular Engineering
- Henan Key Laboratory of Chemical Biology and Organic Chemistry
- Zhengzhou University
- Zhengzhou 450001
- People's Republic of China
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43
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Ehnbom A, Ghosh SK, Lewis KG, Gladysz JA. Octahedral Werner complexes with substituted ethylenediamine ligands: a stereochemical primer for a historic series of compounds now emerging as a modern family of catalysts. Chem Soc Rev 2016; 45:6799-6811. [PMID: 27761532 DOI: 10.1039/c6cs00604c] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
As reported by Alfred Werner in 1911-1912, salts of the formally D3 symmetric [Co(en)3]3+ (en = ethylenediamine) trication were among the first chiral inorganic compounds to be resolved into enantiomers, the absolute configurations of which are denoted Λ (left handed helix) or Δ (right handed helix). After a >100 year dormant period during which few useful reactions of these substitution inert complexes were described, carbon substituted derivatives have recently been found to be potent catalysts for enantioselective organic synthesis. This review systematically outlines the fascinating range of stereoisomers that can arise, such as conformers associated with the five membered chelate rings (λ/δ), alignment modes of the C-C bonds with the C3 symmetry axis (lel/ob), geometric isomers (fac/mer), and configurational diastereomers (R/S) arising from carbon stereocenters. These analyses demonstrate a profound stereochemical diversity that can be applied in catalyst optimization. Efforts are made to bridge the often orthogonal nomenclature systems inorganic and organic chemists employ to describe these phenomena.
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Affiliation(s)
- Andreas Ehnbom
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, USA.
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44
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Xu W, Shen X, Ma Q, Gong L, Meggers E. Restricted Conformation of a Hydrogen Bond Mediated Catalyst Enables the Highly Efficient Enantioselective Construction of an All-Carbon Quaternary Stereocenter. ACS Catal 2016. [DOI: 10.1021/acscatal.6b02080] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Weici Xu
- College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Xiang Shen
- College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Qiao Ma
- College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Lei Gong
- College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
| | - Eric Meggers
- College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
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45
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Xu W, Arieno M, Löw H, Huang K, Xie X, Cruchter T, Ma Q, Xi J, Huang B, Wiest O, Gong L, Meggers E. Metal-Templated Design: Enantioselective Hydrogen-Bond-Driven Catalysis Requiring Only Parts-per-Million Catalyst Loading. J Am Chem Soc 2016; 138:8774-80. [PMID: 27336458 DOI: 10.1021/jacs.6b02769] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Based on a metal-templated approach using a rigid and globular structural scaffold in the form of a bis-cyclometalated octahedral iridium complex, an exceptionally active hydrogen-bond-mediated asymmetric catalyst was developed and its mode of action investigated by crystallography, NMR, computation, kinetic experiments, comparison with a rhodium congener, and reactions in the presence of competing H-bond donors and acceptors. Relying exclusively on weak forces, the enantioselective conjugate reduction of nitroalkenes can be executed at catalyst loadings as low as 0.004 mol% (40 ppm), representing turnover numbers of up to 20 250. A rate acceleration by the catalyst of 2.5 × 10(5) was determined. The origin of the catalysis is traced to an effective stabilization of developing charges in the transition state by carefully orchestrated hydrogen-bonding and van der Waals interactions between catalyst and substrates. This study demonstrates that the proficiency of asymmetric catalysis merely driven by hydrogen-bonding and van der Waals interactions can rival traditional activation through direct transition metal coordination of the substrate.
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Affiliation(s)
- Weici Xu
- College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, People's Republic of China
| | - Marcus Arieno
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Henrik Löw
- Fachbereich Chemie, Philipps-Universität Marburg , Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Kaifang Huang
- College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, People's Republic of China
| | - Xiulan Xie
- Fachbereich Chemie, Philipps-Universität Marburg , Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Thomas Cruchter
- Fachbereich Chemie, Philipps-Universität Marburg , Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Qiao Ma
- College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, People's Republic of China
| | - Jianwei Xi
- College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, People's Republic of China
| | - Biao Huang
- College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, People's Republic of China
| | - Olaf Wiest
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States.,Lab of Computational Chemistry and Drug Discovery, Lab of Chemical Genomics, Peking University Shenzhen Graduate School , Shenzhen 518055, People's Republic of China
| | - Lei Gong
- College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, People's Republic of China
| | - Eric Meggers
- College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, People's Republic of China.,Fachbereich Chemie, Philipps-Universität Marburg , Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
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46
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Ghosh SK, Ganzmann C, Bhuvanesh N, Gladysz JA. Werner-Komplexe mit ω-Dimethylaminoalkyl-substitutierten Ethylendiaminliganden: bifunktionale H-Brückendonor-Katalysatoren für hoch enantioselektive Michael-Additionen. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201511314] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Subrata K. Ghosh
- Department of Chemistry; Texas A&M University; PO Box 30012 College Station TX 77842-3012 USA
| | - Carola Ganzmann
- Institut für Organische Chemie und Interdisciplinary Center for Molecular Materials; Friedrich-Alexander-Universität Erlangen-Nürnberg; Henkestraße 42 91054 Erlangen Deutschland
| | - Nattamai Bhuvanesh
- Department of Chemistry; Texas A&M University; PO Box 30012 College Station TX 77842-3012 USA
| | - John A. Gladysz
- Department of Chemistry; Texas A&M University; PO Box 30012 College Station TX 77842-3012 USA
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47
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Ghosh SK, Ganzmann C, Bhuvanesh N, Gladysz JA. Werner Complexes with ω-Dimethylaminoalkyl Substituted Ethylenediamine Ligands: Bifunctional Hydrogen-Bond-Donor Catalysts for Highly Enantioselective Michael Additions. Angew Chem Int Ed Engl 2016; 55:4356-60. [PMID: 26918320 DOI: 10.1002/anie.201511314] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Revised: 01/02/2016] [Indexed: 01/02/2023]
Abstract
The racemic carbonate complex [Co(en)2 O2 CO](+) Cl(-) (en=1,2-ethylenediamine) and (S)-[H3 NCH((CH2 )n NHMe2 )CH2 NH3 ](3+) 3 Cl(-) (n=1-4) react (water, charcoal, 100 °C) to give [Co(en)2 ((S)-H2 NCH((CH2 )n NHMe2 )CH2 NH2 )](4+) 4 Cl(-) (3 a-d H(4+) 4 Cl(-) ) as a mixture of Λ/Δ diastereomers that separate on chiral-phase Sephadex columns. These are treated with NaOH/Na(+) BArf (-) (BArf =B(3,5-C6 H3 (CF3 )2 )4 ) to give lipophilic Λ- and Δ-3 a-d(3+) 3 BArf (-) , which are screened as catalysts (10 mol %) for additions of dialkyl malonates to nitroalkenes. Optimal results are obtained with Λ-3 c(3+) 3 BArf (-) (CH2 Cl2 , -35 °C; 98-82 % yields and 99-93 % ee for six β-arylnitroethenes). The monofunctional catalysts Λ- and Δ-[Co(en)3 ](3+) 3 BArf (-) give enantioselectivities of <10 % ee with equal loadings of Et3 N. The crystal structure of Δ-3 a H(4+) 4 Cl(-) provides a starting point for speculation regarding transition-state assemblies.
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Affiliation(s)
- Subrata K Ghosh
- Department of Chemistry, Texas A&M University, PO Box 30012, College Station, TX, 77842-3012, USA
| | - Carola Ganzmann
- Institut für Organische Chemie and Interdisciplinary Center for Molecular Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestrasse 42, 91054, Erlangen, Germany
| | - Nattamai Bhuvanesh
- Department of Chemistry, Texas A&M University, PO Box 30012, College Station, TX, 77842-3012, USA
| | - John A Gladysz
- Department of Chemistry, Texas A&M University, PO Box 30012, College Station, TX, 77842-3012, USA.
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48
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Kumar A, Ghosh SK, Gladysz JA. Tris(1,2-diphenylethylenediamine)cobalt(III) Complexes: Chiral Hydrogen Bond Donor Catalysts for Enantioselective α-Aminations of 1,3-Dicarbonyl Compounds. Org Lett 2016; 18:760-3. [PMID: 26820242 DOI: 10.1021/acs.orglett.6b00023] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The enantiopure salt Δ-[Co((S,S)-dpen)3](3+)2Cl(-)B(C6F5)4(-) is an effective hydrogen bond donor catalyst for additions of 1,3-dicarbonyl compounds to di-tert-butyl azodicarboxylate in the presence of N-methylmorpholine (1.0:1.0:0.10) in CH3CN at 0 °C, as illustrated with educts derived from five- or six-membered ring ketones (99-88% yields, >99-91% ee) and cycloheptanone (94%, 72% ee) as well as 2-cyanocyclopentanone (92%, 45% ee) and an acyclic system (98%, >99% ee).
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Affiliation(s)
- Anil Kumar
- Department of Chemistry, Texas A&M University , P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - Subrata K Ghosh
- Department of Chemistry, Texas A&M University , P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - John A Gladysz
- Department of Chemistry, Texas A&M University , P.O. Box 30012, College Station, Texas 77842-3012, United States
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49
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Ma Q, Gong L, Meggers E. Enantioselective β-alkylation of pyrroles with the formation of an all-carbon quaternary stereocenter. Org Chem Front 2016. [DOI: 10.1039/c6qo00273k] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A substitutionally and configurationally inert octahedral chiral-at-metal iridium complex is reported to be an efficient catalyst for the enantioselective Friedel–Crafts alkylation of 2,5-disubstituted pyrroles at the β-position using nitroacrylates as electrophiles.
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Affiliation(s)
- Qiao Ma
- Key Laboratory for Chemical Biology of Fujian Province and Department of Chemical Biology
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
- People's Republic of China
| | - Lei Gong
- Key Laboratory for Chemical Biology of Fujian Province and Department of Chemical Biology
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
- People's Republic of China
| | - Eric Meggers
- Key Laboratory for Chemical Biology of Fujian Province and Department of Chemical Biology
- College of Chemistry and Chemical Engineering
- Xiamen University
- Xiamen 361005
- People's Republic of China
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50
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Rulev YA, Larionov VA, Lokutova AV, Moskalenko MA, Lependina OL, Maleev VI, North M, Belokon YN. Chiral Cobalt(III) Complexes as Bifunctional Brønsted Acid-Lewis Base Catalysts for the Preparation of Cyclic Organic Carbonates. CHEMSUSCHEM 2016; 9:216-222. [PMID: 26663897 DOI: 10.1002/cssc.201501365] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 11/12/2015] [Indexed: 06/05/2023]
Abstract
Stereochemically inert cationic cobalt(III) complexes were shown to be one-component catalysts for the synthesis of cyclic carbonates from epoxides and carbon dioxide at 50 °C and 5 MPa carbon dioxide pressure. The optimal catalyst possessed an iodide counter anion and could be recycled. A catalytic cycle is proposed in which the ligand of the cobalt complexes acts as a hydrogen-bond donor, activating the epoxide towards ring opening by the halide anion and activating the carbon dioxide for subsequent reaction with the halo-alkoxide. No kinetic resolution was observed when terminal epoxides were used as substrates, but chalcone oxide underwent kinetic resolution.
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Affiliation(s)
- Yuri A Rulev
- Nesmeyanov Institute of Organoelement Compounds, Moscow, 19991, Russia
| | | | | | | | - Ol'ga L Lependina
- Nesmeyanov Institute of Organoelement Compounds, Moscow, 19991, Russia
| | - Victor I Maleev
- Nesmeyanov Institute of Organoelement Compounds, Moscow, 19991, Russia
| | - Michael North
- Green Chemistry Centre of Excellence, Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK.
| | - Yuri N Belokon
- Nesmeyanov Institute of Organoelement Compounds, Moscow, 19991, Russia.
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