Catalytic and asymmetric [2,3]sigmatropic rearrangement: Co(III)-salen catalyzed S-ylide formation from allyl aryl sulfides and their rearrangement

Article abstract of DOI:10.1016/S0040-4020(98)01065-5

Reaction of allyl aryl sulfides and α-diazoacetic acid esters in the presence of optically active Co(III)-salen complex (8-Br) provided 3- substituted 2-arylthio-4-pentenoic acid esters stereoselectively by way of enantioselective S-ylide formation and subsequent diastereoselective [2,3]sigmatropic rearrangement. For example, the reaction of cinnamyl phenyl sulfide and (-)-menthyl α-diazoacetate provided (-)-menthyl (2R,3S)-2- phenylthio-3-phenyl-4-pentenoate of 74% de preferentially.