Polymer-Supported Organocatalysts: Asymmetric Reduction of Imines with Trichlorosilane Catalyzed by an Amino Acid-Derived Formamide Anchored to a Polymer

• Published in: Journal of organic chemistry Vol. 73; no. 11; pp. 3985 - 3995
• Main Authors: Malkov, Andrei V, Figlus, Marek, Kočovský, Pavel
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 06-06-2008
• Subjects: Amino Acids - chemistry; Catalysis; Catalytic reactions; Chemistry; Exact sciences and technology; Formamides - chemistry; General and physical chemistry; Imines - chemistry; Kinetics and mechanisms; Magnetic Resonance Spectroscopy; Organic chemistry; Oxidation-Reduction; Polymers - chemistry; Reactivity and mechanisms; Silanes - chemistry; Spectrometry, Mass, Electrospray Ionization; Spectrophotometry, Infrared; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Catalytic reaction; Enantioselectivity; Polymer; Chiral compound; Imine; Supported catalyst; Chemical reduction; Amine; Formamide; Asymmetric synthesis; Aminoacid; Ketimine; Enantiomeric excess; Lewis base; Chemical synthesis; Room temperature; Catalyst support
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo800094q

Asymmetric reduction of ketimines 1a−e with trichlorosilane can be catalyzed by the N-methylvaline-derived Lewis basic formamide anchored to a polymeric support (5a and 5b) with good enantioselectivity (≤82% ee) and low catalyst loading (typically 15 mol %) at room temperature. This protocol represents a considerable simplification of the isolation procedure and is particularly suitable for a parallel synthesis of chiral amines 2a−e. The polymer-supported catalysts retain full activity after a multiple use.