New Multicomponent Approach for the Creation of Chiral Quaternary Centers in the Carbcnyl Allylation Reactions

摘要

The combined regio- and stereo-controlled carbometalation reaction of alkynyl sulfoxide followed by a zinc homologation and finally an allylation reaction led,in a single-pot operation,to chiral homoallylic alcohols in excellent yields and diastereoselectivities for the creation of chiral quaternary and tertiary centers.The key features in all of the reactions that are described in this article are the high degree of stereocontrol,the level of predictability,and "the ease of execution" which ensures success in the application of such methods.The chiral sulfinyl moiety can be finally removed by simple treatment with alkyllithiums,which allows further functionalizations of the carbon skeleton.By using one of these methods,the creation of chiral quaternary centers with the smallest possible difference,namely CD_3 versus CH_3 and ~(13)CH_3 versus CH_3,was easily performed.