1
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Kanbe A, Yokoi K, Yamada Y, Tsurui M, Kitagawa Y, Hasegawa Y, Ogata D, Yuasa J, Aoki S. Optical Resolution of Carboxylic Acid Derivatives of Homoleptic Cyclometalated Iridium(III) Complexes via Diastereomers Formed with Chiral Auxiliaries. Inorg Chem 2023; 62:11325-11341. [PMID: 37432912 PMCID: PMC10369494 DOI: 10.1021/acs.inorgchem.3c00685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Indexed: 07/13/2023]
Abstract
We report on a facile method for the optical resolution of cyclometalated iridium(III) (Ir(III)) complexes via diastereomers formed with chiral auxiliaries. The racemic carboxylic acids of Ir(III) complexes (fac-4 (fac-Ir(ppyCO2H)3 (ppy: 2-phenylpyridine)), fac-6 (fac-Ir(tpyCO2H)3 (tpy: 2-(4'-tolyl)pyridine)), and fac-13 (fac-Ir(mpiqCO2H)3 (mpiq: 1-(4'-methylphenyl)isoquinoline))) were converted into the diastereomers, Δ- and Λ-forms of fac-9 (from fac-6), fac-10 (from fac-4), fac-11 (from fac-6), and fac-14 (from fac-13), respectively, by the condensation with (1R,2R)-1,2-diaminocyclohexane or (1R,2R)-2-aminocyclohexanol. The resulting diastereomers were separated by HPLC (with a nonchiral column) or silica gel column chromatography, and their absolute stereochemistry was determined by X-ray single-crystal structure analysis and CD (circular dichroism) spectra. Spectra of all diastereomers of the Ir(III) complexes are reported. Hydrolysis of the ester moieties of Δ- and Λ-forms of fac-10, fac-11, and fac-14 gave both enantiomers of the corresponding carboxylic acid derivatives in the optically pure forms, Δ-fac and Λ-fac-4, -6, and -13, respectively.
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Affiliation(s)
- Azusa Kanbe
- Faculty
of Pharmaceutical Science, Tokyo University
of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
| | - Kenta Yokoi
- Faculty
of Pharmaceutical Science, Tokyo University
of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
| | - Yasuyuki Yamada
- Department
of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
- Research
Center for Materials Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
- JST,
PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Makoto Tsurui
- Graduate
School of Chemical Sciences and Engineering, Hokkaido University, N13W8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan
| | - Yuichi Kitagawa
- Faculty of
Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-Ku, Sapporo, Hokkaido 060-8628, Japan
- Institute
for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Kita-21, Nishi-10, Kita-Ku, Sapporo, Hokkaido 001-0021, Japan
| | - Yasuchika Hasegawa
- Faculty of
Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-Ku, Sapporo, Hokkaido 060-8628, Japan
- Institute
for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Kita-21, Nishi-10, Kita-Ku, Sapporo, Hokkaido 001-0021, Japan
| | - Daiji Ogata
- Faculty
of Science, Tokyo University of Science, 1-3 Kagurazaka,
Shinjuku-ku, Tokyo 162-8601, Japan
| | - Junpei Yuasa
- Faculty
of Science, Tokyo University of Science, 1-3 Kagurazaka,
Shinjuku-ku, Tokyo 162-8601, Japan
| | - Shin Aoki
- Faculty
of Pharmaceutical Science, Tokyo University
of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
- Research
Institute for Science and Technology (RIST), Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
- Research
Institute for Biomedical Science (RIBS), Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
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2
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Demirel N, Haber J, Ivlev SI, Meggers E. Improving the Configurational Stability of Chiral-at-Iron Catalysts Containing Two N-(2-Pyridyl)-Substituted N-Heterocyclic Carbene Ligands. Organometallics 2022; 41:3852-3860. [PMID: 36590905 PMCID: PMC9795549 DOI: 10.1021/acs.organomet.2c00492] [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] [Received: 09/29/2022] [Indexed: 11/27/2022]
Abstract
Recently, we introduced the first example of chiral-at-iron catalysts in which two achiral N-(2-pyridyl)-substituted N-heterocyclic carbene (NHC) ligands in addition to two labile acetonitriles are coordinated around a central iron, to generate a stereogenic metal center [Hong Y.Chiral-at-Iron Catalyst: Expanding the Chemical Space for Asymmetric Earth-Abundant Metal Catalysis. J. Am. Chem. Soc.2019, 141, 4569-4572]. A more facile synthesis of such chiral-at-iron catalysts was developed, which omits the use of expensive silver salts and an elaborate electrochemical setup. Configurational robustness was improved by replacing the imidazol-2-ylidene carbene moieties with benzimidazol-2-ylidenes. The π-acceptor properties of the altered NHCs were investigated by Ganter's 77Se NMR method. The obtained benzimidazol-2-ylidene chiral-at-iron complex is an excellent catalyst for an asymmetric hetero-Diels-Alder reaction under open-flask conditions.
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3
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Stimuli-responsive chirality inversion of metallohelices and related dynamic metal complexes. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214582] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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4
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Han F, Choi PH, Ye CX, Grell Y, Xie X, Ivlev SI, Chen S, Meggers E. Cyclometalated Chiral-at-Ruthenium Catalyst for Enantioselective Ring-Closing C(sp 3)–H Carbene Insertion to Access Chiral Flavanones. ACS Catal 2022. [DOI: 10.1021/acscatal.2c02423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Feng Han
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, Marburg 35043, Germany
| | - Peter H. Choi
- Department of Chemistry and Biochemistry, Oberlin College, Oberlin, Ohio 44074, United States
| | - Chen-Xi Ye
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, Marburg 35043, Germany
| | - Yvonne Grell
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, Marburg 35043, Germany
| | - Xiulan Xie
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, Marburg 35043, Germany
| | - Sergei I. Ivlev
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, Marburg 35043, Germany
| | - Shuming Chen
- Department of Chemistry and Biochemistry, Oberlin College, Oberlin, Ohio 44074, United States
| | - Eric Meggers
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, Marburg 35043, Germany
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5
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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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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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7
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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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8
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Steinlandt PS, Xie X, Ivlev S, Meggers E. Stereogenic-at-Iron Catalysts with a Chiral Tripodal Pentadentate Ligand. ACS Catal 2021. [DOI: 10.1021/acscatal.1c01675] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Philipp S. Steinlandt
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Xiulan Xie
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany
| | - Sergei Ivlev
- 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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9
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Bis-Cyclometalated Indazole and Benzimidazole Chiral-at-Iridium Complexes: Synthesis and Asymmetric Catalysis. Molecules 2021; 26:molecules26071822. [PMID: 33804954 PMCID: PMC8037582 DOI: 10.3390/molecules26071822] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 03/22/2021] [Accepted: 03/22/2021] [Indexed: 11/17/2022] Open
Abstract
A new class of bis-cyclometalated iridium(III) catalysts containing two inert cyclometalated 6-tert-butyl-2-phenyl-2H-indazole bidentate ligands or two inert cyclometalated 5-tert-butyl-1-methyl-2-phenylbenzimidazoles is introduced. The coordination sphere is complemented by two labile acetonitriles, and a hexafluorophosphate ion serves as a counterion for the monocationic complexes. Single enantiomers of the chiral-at-iridium complexes (>99% er) are obtained through a chiral-auxiliary-mediated approach using a monofluorinated salicyloxazoline and are investigated as catalysts in the enantioselective conjugate addition of indole to an α,β-unsaturated 2-acyl imidazole and an asymmetric Nazarov cyclization.
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10
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Steinlandt PS, Zuo W, Harms K, Meggers E. Bis-Cyclometalated Indazole Chiral-at-Rhodium Catalyst for Asymmetric Photoredox Cyanoalkylations. Chemistry 2019; 25:15333-15340. [PMID: 31541505 PMCID: PMC6916287 DOI: 10.1002/chem.201903369] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 09/02/2019] [Indexed: 01/23/2023]
Abstract
A new class of bis‐cyclometalated rhodium(III) catalysts containing two inert cyclometalated 6‐tert‐butyl‐2‐phenyl‐2H‐indazole ligands and two labile acetonitriles is introduced. Single enantiomers (>99 % ee) were obtained through a chiral‐auxiliary‐mediated approach using a monofluorinated salicyloxazoline. The new chiral‐at‐metal complex is capable of catalyzing the visible‐light‐induced enantioselective α‐cyanoalkylation of 2‐acyl imidazoles in which it serves a dual function as the chiral Lewis acid catalyst for the asymmetric radical chemistry and at the same time as the photoredox catalyst for the visible‐light‐induced redox chemistry (up to 80 % yield, 4:1 d.r., and 95 % ee, 12 examples).
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Affiliation(s)
- Philipp S Steinlandt
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043, Marburg, Germany
| | - Wei Zuo
- 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
| | - Eric Meggers
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043, Marburg, Germany
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11
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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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12
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Haghdoost MM, Zwettler N, Golbaghi G, Belaj F, Bagherzadeh M, Schachner JA, Mösch‐Zanetti NC. Diastereoselective Synthesis and Catalytic Activity of Two Chiral
cis
‐Dioxidomolybdenum(VI) Complexes. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201800285] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
| | - Niklas Zwettler
- Institute of Chemistry University of Graz Schubertstr. 1 8010 Graz Austria
| | - Golara Golbaghi
- Chemistry Department Sharif University of Technology P.O. Box 11155 3615 Tehran Iran
| | - Ferdinand Belaj
- Institute of Chemistry University of Graz Schubertstr. 1 8010 Graz Austria
| | - Mojtaba Bagherzadeh
- Chemistry Department Sharif University of Technology P.O. Box 11155 3615 Tehran Iran
| | - Jörg A. Schachner
- Institute of Chemistry University of Graz Schubertstr. 1 8010 Graz Austria
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13
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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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14
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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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15
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Zheng Y, Harms K, Zhang L, Meggers E. Enantioselective Alkynylation of 2-Trifluoroacetyl Imidazoles Catalyzed by Bis-Cyclometalated Rhodium(III) Complexes Containing Pinene-Derived Ligands. Chemistry 2016; 22:11977-81. [DOI: 10.1002/chem.201602372] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Indexed: 12/28/2022]
Affiliation(s)
- Yu Zheng
- 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
| | - 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
- College of Chemistry and Chemical Engineering; Xiamen University; Xiamen 361005 P. R. China
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16
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Ma J, Shen X, Harms K, Meggers E. Expanding the family of bis-cyclometalated chiral-at-metal rhodium(iii) catalysts with a benzothiazole derivative. Dalton Trans 2016; 45:8320-3. [PMID: 27143346 DOI: 10.1039/c6dt01063f] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Synthetic access to previously elusive single enantiomers of an octahedral chiral-at-metal rhodium(iii) complex containing two cyclometalated 2-phenylbenzothiazoles and two acetonitrile ligands is reported. The complex is a superior chiral Lewis acid catalyst compared to its benzoxazole congener which can be rationalized with a higher steric congestion around the coordination sites.
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Affiliation(s)
- Jiajia Ma
- Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, Germany.
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17
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Asymmetric Friedel–Crafts alkylation of indoles with 2-nitro-3-arylacrylates catalyzed by a metal-templated hydrogen bonding catalyst. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2015.06.046] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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18
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Shen X, Huo H, Wang C, Zhang B, Harms K, Meggers E. Octahedral Chiral-at-Metal Iridium Catalysts: Versatile Chiral Lewis Acids for Asymmetric Conjugate Additions. Chemistry 2015; 21:9720-6. [PMID: 26033287 DOI: 10.1002/chem.201500922] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Indexed: 01/10/2023]
Abstract
Octahedral iridium(III) complexes containing two bidentate cyclometalating 5-tert-butyl-2-phenylbenzoxazole (IrO) or 5-tert-butyl-2-phenylbenzothiazole (IrS) ligands in addition to two labile acetonitrile ligands are demonstrated to constitute a highly versatile class of asymmetric Lewis acid catalysts. These complexes feature the metal center as the exclusive source of chirality and serve as effective asymmetric catalysts (0.5-5.0 mol % catalyst loading) for a variety of reactions with α,β-unsaturated carbonyl compounds, namely Friedel-Crafts alkylations (94-99% ee), Michael additions with CH-acidic compounds (81-97% ee), and a variety of cycloadditions (92-99% ee with high d.r.). Mechanistic investigations and crystal structures of an iridium-coordinated substrates and iridium-coordinated products are consistent with a mechanistic picture in which the α,β-unsaturated carbonyl compounds are activated by two-point binding (bidentate coordination) to the chiral Lewis acid.
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Affiliation(s)
- Xiaodong Shen
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35043 Marburg (Germany)
| | - Haohua Huo
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35043 Marburg (Germany)
| | - Chuanyong Wang
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35043 Marburg (Germany)
| | - Bo Zhang
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35043 Marburg (Germany)
| | - Klaus Harms
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35043 Marburg (Germany)
| | - Eric Meggers
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35043 Marburg (Germany). .,College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, (P. R. China).
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19
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Wang C, Lu Z. Catalytic enantioselective organic transformations via visible light photocatalysis. Org Chem Front 2015. [DOI: 10.1039/c4qo00306c] [Citation(s) in RCA: 138] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Enantioselective transformations via visible light photocatalysis are discussed and could have a strong impact on asymmetric photoreactions.
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Affiliation(s)
| | - Zhan Lu
- Department of chemistry
- Zhejiang University
- Hangzhou
- China
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20
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Huo H, Fu C, Harms K, Meggers E. Asymmetric Catalysis with Substitutionally Labile yet Stereochemically Stable Chiral-at-Metal Iridium(III) Complex. J Am Chem Soc 2014; 136:2990-3. [DOI: 10.1021/ja4132505] [Citation(s) in RCA: 143] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Haohua Huo
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35043 Marburg, Germany
| | - Chen Fu
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35043 Marburg, Germany
| | - Klaus Harms
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35043 Marburg, Germany
| | - Eric Meggers
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35043 Marburg, Germany
- College
of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
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21
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22
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Kraack M, Harms K, Meggers E. Reductive Labilization of a Cyclometalating Ligand Applied to Auxiliary-Mediated Asymmetric Coordination Chemistry. Organometallics 2013. [DOI: 10.1021/om4006627] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Marianne Kraack
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35043 Marburg, Germany
| | - Klaus Harms
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35043 Marburg, Germany
| | - Eric Meggers
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35043 Marburg, Germany
- College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People’s Republic of China
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23
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Huang B, Wang L, Gong L, Meggers E. Chiral Enol Oxazolines and Thiazolines as Auxiliary Ligands for the Asymmetric Synthesis of Ruthenium-Polypyridyl Complexes. Chem Asian J 2013; 8:2274-80. [DOI: 10.1002/asia.201300598] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Indexed: 01/28/2023]
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24
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Chen LA, Xu W, Huang B, Ma J, Wang L, Xi J, Harms K, Gong L, Meggers E. Asymmetric catalysis with an inert chiral-at-metal iridium complex. J Am Chem Soc 2013; 135:10598-601. [PMID: 23672419 DOI: 10.1021/ja403777k] [Citation(s) in RCA: 118] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The development of a chiral-at-metal iridium(III) complex for the highly efficient catalytic asymmetric transfer hydrogenation of β,β'-disubstituted nitroalkenes is reported. Catalysis by this inert, rigid metal complex does not involve any direct metal coordination but operates exclusively through weak interactions with functional groups properly arranged in the ligand sphere of the iridium complex. Although the iridium complex relies only on the formation of three hydrogen bonds, it exceeds the performance of most organocatalysts with respect to enantiomeric excess (up to 99% ee) and catalyst loading (down to 0.1 mol %). This work hints at an advantage of structurally complicated rigid scaffolds for non-covalent catalysis, which especially relies on conformationally constrained cooperative interactions between the catalyst and substrates.
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Affiliation(s)
- Liang-An Chen
- Fujian Provincial Key Laboratory of Chemical Biology, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, People's Republic of China
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25
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Jung J, Jo J, Laskar M, Lee D. Stereodynamics of Metal-Ligand Assembly: What Lies Beneath the “Simple” Spectral Signatures ofC2-Symmetric Chiral Chelates. Chemistry 2013; 19:5156-68. [DOI: 10.1002/chem.201204216] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Indexed: 11/09/2022]
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26
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Chen LA, Ding X, Gong L, Meggers E. Thioether-based anchimeric assistance for asymmetric coordination chemistry with ruthenium(ii) and osmium(ii). Dalton Trans 2013; 42:5623-6. [DOI: 10.1039/c3dt00015j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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27
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Mollin S, Blanck S, Harms K, Meggers E. Cyclometalated phenylquinoline rhodium complexes as protein kinase inhibitors. Inorganica Chim Acta 2012. [DOI: 10.1016/j.ica.2012.04.035] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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28
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Fu C, Wenzel M, Treutlein E, Harms K, Meggers E. Proline as chiral auxiliary for the economical asymmetric synthesis of ruthenium(II) polypyridyl complexes. Inorg Chem 2012; 51:10004-11. [PMID: 22946499 DOI: 10.1021/ic3015157] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A straightforward method for the synthesis of virtually enantiomerically pure ruthenium(II) polypyridyl complexes [Ru(pp)(pp')(pp")](PF(6))(2), pp = bidentate polypyridyl has been developed. The synthesis draws from the readily available racemic starting material cis-[Ru(pp)(pp')Cl(2)] and the natural amino acids l- or d-proline and relies on a dynamic asymmetric transformation under thermodynamic control.
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Affiliation(s)
- Chen Fu
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse, 35043 Marburg, Germany
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29
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Chen LA, Ma J, Celik MA, Yu HL, Cao Z, Frenking G, Gong L, Meggers E. Active versus passive substituent participation in the auxiliary-mediated asymmetric synthesis of an octahedral metal complex. Chem Asian J 2012; 7:2523-6. [PMID: 22915359 DOI: 10.1002/asia.201200532] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Indexed: 11/07/2022]
Abstract
Ambiguous chirality transfer: A surprising reversal of chirality transfer from carbon to metal is reported in the asymmetric synthesis of a chiral ruthenium complex, affording the metal-centered configuration Λ or Δ depending only on the chemical composition of the side chain of a chiral salicyloxazoline auxiliary.
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Affiliation(s)
- Liang-An Chen
- College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, PR China
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30
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Wenzel M, Meggers E. Chiral (Mercaptophenyl)oxazolines as Auxiliaries for Asymmetric Coordination Chemistry. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201200203] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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31
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Tan YH, Wu JJ, Zhou HY, Yang LF, Ye BH. Anion and pH induced spontaneous resolution of Δ- and Λ-[M(H2Biim)3]SO4 (M = Ru2+, Co2+, Ni2+, Mn2+, Fe2+, and Zn2+) enantiomers. CrystEngComm 2012. [DOI: 10.1039/c2ce26334c] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Lin Z, Celik MA, Fu C, Harms K, Frenking G, Meggers E. N-Sulfinylcarboximidates as a New Class of Chiral Bidentate Ligands: Application to Asymmetric Coordination Chemistry. Chemistry 2011; 17:12602-5. [DOI: 10.1002/chem.201101886] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Indexed: 11/11/2022]
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33
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Theoretical study on vibrational circular dichroism spectra of tris(acetylacetonato)metal(III) complexes: Anharmonic effects and low-lying excited states. J Chem Phys 2011; 135:084506. [DOI: 10.1063/1.3624605] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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34
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Affiliation(s)
- Eric Meggers
- Fachbereich Chemie, Philipps‐Universität Marburg, Hans‐Meerwein‐Straße, 35043 Marburg, Germany
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35
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Lin R, Zhang H, Li S, Chen L, Zhang W, Wen TB, Zhang H, Xia H. pH-Switchable Inversion of the Metal-Centered Chirality of Metallabenzenes: Opposite Stereodynamics in Reactions of Ruthenabenzene withL- andD-Cysteine. Chemistry 2011; 17:2420-7. [DOI: 10.1002/chem.201001867] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Revised: 09/25/2010] [Indexed: 11/10/2022]
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36
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Gong L, Müller C, Celik MA, Frenking G, Meggers E. 2-Diphenylphosphino-2′-hydroxy-1,1′-binaphthyl as a chiral auxiliary for asymmetric coordination chemistry. NEW J CHEM 2011. [DOI: 10.1039/c0nj00787k] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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37
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Lin Z, Gong L, Celik MA, Harms K, Frenking G, Meggers E. Asymmetric Coordination Chemistry by Chiral-Auxiliary-Mediated Dynamic Resolution under Thermodynamic Control. Chem Asian J 2010; 6:474-81. [DOI: 10.1002/asia.201000555] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Indexed: 11/06/2022]
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38
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Controlling the Helicity of Hydroxyquinoline Metal Complexes Based on a Macrocyclic Peptide Scaffold. European J Org Chem 2009. [DOI: 10.1002/ejoc.200900250] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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39
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Howson SE, Allan LEN, Chmel NP, Clarkson GJ, van Gorkum R, Scott P. Self-assembling optically pure Fe(A-B)3 chelates. Chem Commun (Camb) 2009:1727-9. [PMID: 19294276 DOI: 10.1039/b821573a] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Optically pure, single diastereomer fac-tris(diimine) complexes of Fe(II) are available from a remarkably facile one-pot procedure using a range of readily available (R)-2-phenylglycinol derivatives.
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Affiliation(s)
- Suzanne E Howson
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, UK CV4 7AL
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40
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Chow HS, Constable EC, Frantz R, Housecroft CE, Lacour J, Neuburger M, Rappoport D, Schaffner S. Conformationally-locked metallomacrocycles—prototypes for a novel type of axial chirality. NEW J CHEM 2009. [DOI: 10.1039/b819588a] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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41
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Constable EC, Housecroft CE, Mahmood A. New chiral oligopyridines—4,4′-bis(disaccharide)-functionalised 2,2′-bipyridines and 4′-(disaccharide)-functionalised 2,2′:6′,2′′-terpyridines. Carbohydr Res 2008; 343:2567-75. [DOI: 10.1016/j.carres.2008.08.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2007] [Revised: 07/16/2008] [Accepted: 08/02/2008] [Indexed: 12/01/2022]
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42
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Constable EC, Housecroft CE, Jullien V, Neuburger M, Poleschak I, Reymann S, Saxer S, Schaffner S. Tris-chelate complexes with chiral ligands: In search of diastereoisomeric selectivity with remote stereogenic centres. Polyhedron 2007. [DOI: 10.1016/j.poly.2007.08.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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43
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Sato H, Taniguchi T, Nakahashi A, Monde K, Yamagishi A. Effects of Central Metal Ions on Vibrational Circular Dichroism Spectra of Tris-(β-diketonato)metal(III) Complexes. Inorg Chem 2007; 46:6755-66. [PMID: 17625835 DOI: 10.1021/ic070300i] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Vibrational circular dichroism (VCD) spectra of a series of [M(III)(acac)3] (acac = acetylacetonato; M = Cr, Co, Ru, Rh, Ir, and Al) and [M(III)(acac)2(dbm)] (dbm = dibenzoylmethanato; M = Cr, Co, and Ru) have been investigated experimentally and/or theoretically in order to see the effect of the central metal ion on the vibrational dynamics of ligands. The optical antipodes give the mirror-imaged spectra in the region of 1700-1000 cm(-1). The remarkable effect of the central metal ion is observed experimentally on the VCD peaks due to C-O stretches (1500-1300 cm(-1)) for both [M(III)(acac)3] and [M(III)(acac)2(dbm)]. In the case of Delta-[M(III)(acac)3], for example, the order of frequency of two C-O stretches (E and A2 symmetries) is dependent on the kind of a central metal ion as follows: E (-) > A2 (+) for M = Co, Rh, and Ir, while A2 (+) > E (-) for M = Cr and Ru. In the case of Delta-[M(III)(acac)2(dbm)], the order of frequency of three C-O stretches (A, B, and B symmetries) is as follows: A (-) > B (+) > B (+) for Co(III), B (+) > A (-) > B (-) for Cr(III), and A (-) > B (+) > B (-) for Ru(III). These results imply that the energy levels of C-O stretches are delicately affected by the kind of central metal ion. Since such detailed information is not obtained from the IR spectra alone, the VCD spectrum can probe the effect of the central metal ion on interligand cooperative vibration modes.
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Affiliation(s)
- Hisako Sato
- Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan
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44
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Furuno Y, Sato H, Yoshida J, Hoshino N, Fukuda Y, Yamagishi A. Linkage Effects of Chromium(III) Acetylacetonato Units on Chiral Induction of Liquid Crystal Phases. J Phys Chem B 2006; 111:521-6. [PMID: 17228909 DOI: 10.1021/jp065586b] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The linkage effects of polynuclear metal complexes on chiral induction have been studied by application of the chiral oligomers of acetylacetonato chromium(III) units as a dopant, inducing chiral nematic phases. The compounds were prepared by reacting [Cr(acac)(3)] (acac = acetylacetonato) and 1,1,2,2-tetraacetylethane (taetH(2)) in solid phase at 160 degrees C. Binuclear diastereomers were separated on a silica gel column, followed by chromatographic resolution on a chiral column packed with an ion-exchange adduct of Delta-[Ru(phen)(3)](2+) (phen = 1,10-phenanthroline) and synthetic hectorite. An enantiomeric pair (DeltaDelta- and LambdaLambda-[Cr(acac)(2)(taet)Cr-(acac)(2)]) and a meso species (DeltaLambda-[Cr(acac)(2)(taet)Cr(acac)(2)]) were identified. The binuclear enantiomers were doped into a room-temperature nematic liquid crystal, N-methoxybenzylidene-4-n-butylaniline. Helical twisting power (beta(M)) was found to be +97.9 and -88.9 microm(-1) for LambdaLambda- and DeltaDelta-[Cr(acac)(2)(taet)Cr(acac)(2)], respectively. The values were compared with beta(M) for the monomeric enantiomers (+99.5 and -91.0 microm(-1) for Lambda- and Delta-[Cr(acac)(3)], respectively). The results are interpreted on the basis of the surface chirality model. DeltaDelta-[Cr(acac)(2)(taet)Cr(acac)(2)] was found to photoisomerize both in a hexane solution and in a liquid crystal phase of ZLI-1132. The quantum yield of photoisomerization in a liquid crystal phase was lowered to ca. 30% of that in a hexane solution.
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Affiliation(s)
- Yuka Furuno
- Department of Chemistry, Faculty of Science, Ochanomizu University, Tokyo 112-8610, Japan
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45
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Tandura SN, Shumsky AN, Ugrak BI, Negrebetsky VV, Bylikin SY, Kolesnikov SP. Stereochemical Flexibility of Bis(amidomethyl)dichlorogermanes. A Novel Dissociative Mechanism of Ligand Exchange in Neutral Hexacoordinated Bischelate Complexes. Organometallics 2005. [DOI: 10.1021/om0400550] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Stanislav N. Tandura
- N. D. Zelinsky Institute of Organic Chemistry, 47 Leninsky Prosp., 119991 Moscow, Russia, and Russian State Medical University, 1 Ostrovityanov Street, 117997 Moscow, Russia
| | - Aleksey N. Shumsky
- N. D. Zelinsky Institute of Organic Chemistry, 47 Leninsky Prosp., 119991 Moscow, Russia, and Russian State Medical University, 1 Ostrovityanov Street, 117997 Moscow, Russia
| | - Bogdan I. Ugrak
- N. D. Zelinsky Institute of Organic Chemistry, 47 Leninsky Prosp., 119991 Moscow, Russia, and Russian State Medical University, 1 Ostrovityanov Street, 117997 Moscow, Russia
| | - Vadim V. Negrebetsky
- N. D. Zelinsky Institute of Organic Chemistry, 47 Leninsky Prosp., 119991 Moscow, Russia, and Russian State Medical University, 1 Ostrovityanov Street, 117997 Moscow, Russia
| | - Sergey Yu. Bylikin
- N. D. Zelinsky Institute of Organic Chemistry, 47 Leninsky Prosp., 119991 Moscow, Russia, and Russian State Medical University, 1 Ostrovityanov Street, 117997 Moscow, Russia
| | - Stanislav P. Kolesnikov
- N. D. Zelinsky Institute of Organic Chemistry, 47 Leninsky Prosp., 119991 Moscow, Russia, and Russian State Medical University, 1 Ostrovityanov Street, 117997 Moscow, Russia
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46
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Monchaud D, Jodry JJ, Pomeranc D, Heitz V, Chambron JC, Sauvage JP, Lacour J. Ion-Pair-Mediated Asymmetric Synthesis of a Configurationally Stable Mononuclear Tris(diimine)-Iron(II) Complex. Angew Chem Int Ed Engl 2002. [DOI: 10.1002/1521-3757(20020703)114:13<2423::aid-ange2423>3.0.co;2-f] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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47
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Monchaud D, Jodry JJ, Pomeranc D, Heitz V, Chambron JC, Sauvage JP, Lacour J. Ion-pair-mediated asymmetric synthesis of a configurationally stable mononuclear tris(diimine)-iron(II) complex. Angew Chem Int Ed Engl 2002; 41:2317-9. [PMID: 12203578 DOI: 10.1002/1521-3773(20020703)41:13<2317::aid-anie2317>3.0.co;2-w] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- David Monchaud
- Département de Chimie Organique Université de Genève quai Ernest Ansermet 30, 1211 Genève 4, Switzerland
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48
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Lacour J, Londez A. Diastereoselective synthesis of C2-symmetric hexacoordinated phosphate anions (HYPHATs) with predetermined chirality from 1,2-diaryl-ethane-1,2-diols. J Organomet Chem 2002. [DOI: 10.1016/s0022-328x(01)01251-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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