Polymer-supported organocatalysts: asymmetric reduction of imines with trichlorosilane catalyzed by an amino acid-derived formamide anchored to a polymer.
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 (< or =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.
Malkov
Andrei V
AV
Department of Chemistry, WestChem, University of Glasgow, Glasgow, Scotland, U.K. amalkov@chem.gla.ac.uk
Figlus
Marek
M
Kocovský
Pavel
P
D000596:Amino Acids / Q000737:chemistry*; D002384:Catalysis; D005559:Formamides / Q000737:chemistry*; D007097:Imines / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D010084:Oxidation-Reduction; D011108:Polymers / Q000737:chemistry*; D012821:Silanes / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D013055:Spectrophotometry, Infrared
D000596:Amino Acids; D005559:Formamides; D007097:Imines; D011108:Polymers; D012821:Silanes; C065893:trichlorosilane