[75340-59-9] · C15H14O3S · (R)-(+)-Phenyl (p-Toluenesulfinyl)acetate · (MW 274.36)
(asymmetric aldol-type condensations1)
Physical Data: [a]D +87° (CHCl3, c 0.95).
Preparative Methods: conveniently prepared by deprotonation of (R)-(+)-p-tolyl methyl sulfoxide and treatment of the resulting sulfinyl carbanion with phenyl chloroformate (eq 1).1
Asymmetric oxidation of phenyl (p-toluenesulfinyl)acetate with bovine serum albumin (BSA) gave a poor ee (eq 2).2
Aldol-type condensation of the magnesium enolate of (R)-(+)-phenyl (p-toluenesulfinyl)acetate, prepared with t-butylmagnesium bromide, with the aldehyde precursor of maytansine afforded, after desulfurization with Aluminum Amalgam, the desired 4,5-unsaturated 3-(S)-hydroxy ester in high yield and high diastereoselectivity (eq 3).1
Guy Solladié & Françoise Colobert
University Louis Pasteur, Strasbourg, France