Asymmetric Synthesis of Amines with tert-Butanesulfinamide and Its Application

摘要

Tert-Butanesulfmyl imines are exceedingly versatile intermediates for the asymmetric synthesis of amines.Aldimines 15 and ketimines 16 are prepared in high yields under mild conditions by condensing enantiomerically pure fert-butanesulfmamide 10,either enantiomer of which is readily synthesized in large scale from inexpensive reagents,with a wide range of aldehydes and ketones.The tert-butanesulfinyl group activates the imines for the addition of many different classes of nucleophiles,serves as a powerful chiral directing group,and after nucleophilic addition function as a versatile protecting group of the amines,which is readily cleaved by treatment with acid.A wide range of highly enantioenriched amines,including alpha-branched amines,a,alpha-dibranched amines,a- and beta-amino acids,1,2- and 1,3-amino alcohols,and alpha-trifluoromethyl-amines are efficiently synthesized using this methodology.