Erythro-Directive Reduction of α-Substituted Alkanones by Means of Hydrosilanes in Acidic Media

Article abstract of DOI:10.1021/jo00258a004

Hydrosilane reduced α-oxy and α-amino ketones and β-keto acid derivatives in trifluoroacetic acid to afford the corresponding erythro alcohols with high diastereoselectivity.The reaction proceeded without racemization at the carbon α to the carbonyl group.The erythro-directive reduction was explained in terms of the proton-bridged Cram cyclic model and successfully applied to the synthesis of physiologically important amino alcohols such as l-ephedrine, l-methoxamine, and erythro-2-methyl-3-piperidino-1-phenylpropanol.