Enantioselective Organocatalytic Hydride Reduction

• Published in: Journal of the American Chemical Society Vol. 127; no. 1; pp. 32 - 33
• Main Authors: Ouellet, Stéphane G, Tuttle, Jamison B, MacMillan, David W. C
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 12.01.2005; Amer Chemical Soc
• Subjects: Aldehydes - chemistry; Chemistry; Chemistry, Multidisciplinary; Dihydropyridines - chemistry; Exact sciences and technology; Hydrogen - chemistry; Imidazolidines - chemistry; Imines - chemistry; Models, Molecular; Organic chemistry; Oxidation-Reduction; Physical Sciences; Proline - chemistry; Science & Technology; Stereoisomerism; CHEMISTRY; CATALYSIS; Chemical reduction; Hydrogen transfer; Catalytic reaction; Enantioselectivity; Chemoselectivity; Homogeneous catalysis; Carbonyl Organic compounds; Experimental study
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja043834g

The first enantioselective organocatalytic hydride reduction has been accomplished. The use of iminium catalysis has provided a new organocatalytic strategy for the enantioselective reduction of β,β-substituted α,β-unsaturated aldehydes to generate β-stereogenic aldehydes. The use of imidazolidinone 2 as the asymmetric catalyst has been found to mediate the transfer of hydrogen to a large class of enal substrates from ethyl Hantzsch ester. The capacity of catalyst 2 to accelerate E − Z isomerization prior to selective E-olefin reduction allows the implementation of geometrically impure enals in this operationally simple protocol.