Highly Enantioselective Cyclopropanation of Styrenes and Diazoacetates Catalyzed by 3-Oxobutylideneaminatocobalt(II) Complexes, Part 1. Designs of Cobalt Complex Catalysts and the Effects of Donating Ligands
- 1 November 2001
- journal article
- research article
- Published by Oxford University Press (OUP) in Bulletin of the Chemical Society of Japan
- Vol. 74 (11) , 2139-2150
- https://doi.org/10.1246/bcsj.74.2139
Abstract
Highly enantioselective cyclopropanation of styrene derivatives and diazoacetates was effectively catalyzed by reasonably designed 3-oxobutylideneaminatocobalt(II) complexes, whose ligands were prepared from 1,2-dimesitylethylenediamine and alkyl 3-oxobutanoates. The steric demand of the diamine unit of the complexes seriously influenced the enantioselectivity, and the ester groups on their side chains somewhat improved the trans-selectivity. Addition of a catalytic amount of N-methylimidazole significantly accelerated the reaction and enhanced the enantioselectivity due to its coordination to the center cobalt atom of the complex as an axial ligand. Alcoholic or aqueous alcoholic solvents were also effective particularly for the cyclopropanation of 1-substituted 1-phenylethylenes to achieve high enantioselectivity in aqueous methanol.Keywords
This publication has 48 references indexed in Scilit:
- New aspects of catalytic asymmetric cyclopropanationTetrahedron, 1998
- Recent Advances in Asymmetric Catalytic Metal Carbene TransformationsChemical Reviews, 1998
- Semicorrin metal complexes as enantioselective catalysts. Part 2. Enantioselective cyclopropane formation from olefins with diazo compounds catalyzed by chiral (semicorrinato)copper complexesHelvetica Chimica Acta, 1988
- Chiral Copper‐Semicorrin Complexes as Enantioselective Catalysts for the Cyclopropanation of Olefins by Diazo CompoundsAngewandte Chemie International Edition in English, 1986
- Catalytic asymmetric synthesis of cyclopropanecarboxylic acids: an application of chiral copper carbenoid reactionPublished by Walter de Gruyter GmbH ,1985
- Additions and Corrections - A Highly Enantioselective Synthesis of Cyclopropane Derivatives through Chiral Cobalt(II) Complex Catalyzed Carbenoid Reaction. General Scope and Factors Determining the Enantioselectivity.Journal of the American Chemical Society, 1978
- Enantioselective carbenoid cyclopropanation catalyzed by chiral vic-dioximatocobalt(II) complexes prepared from natural camphor and .beta.-pinene. Mechanism and stereochemistryJournal of the American Chemical Society, 1978
- A highly enantioselective synthesis of cyclopropane derivatives through chiral cobalt(II) complex catalyzed carbenoid reaction. General scope and factors determining the enantioselectivityJournal of the American Chemical Society, 1978
- Enantioselective reactions through chiral metal-carbene intermediatesPublished by Walter de Gruyter GmbH ,1978
- Homogeneous catalysis in the decomposition of diazo compounds by copper chelatesTetrahedron, 1968