title: N-tert-butanesulfinyl imines: versatile intermediates for the asymmetric synthesis of amines.
abstract: N-tert-Butanesulfinyl aldimines 3 and ketimines 4 are exceedingly versatile intermediates for the asymmetric synthesis of amines. The N-tert-butanesulfinyl imines are prepared in high yields by condensing enantiomerically pure tert-butanesulfinamide 1, which is readily available in either configuration, 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 is readily cleaved by treatment of the product with acid. A wide range of highly enantioenriched amines, including alpha-branched and alpha,alpha-dibranched amines, alpha- and beta-amino acids, 1,2- and 1,3-amino alcohols, and alpha-trifluoromethyl amines, are efficiently synthesized using this methodology. In addition, N-tert-butanesulfinyl imine derivatives provide a new family of ligands for asymmetric catalysis.
authors.affiliation: Center for New Directions in Organic Synthesis, Department of Chemistry, University of California, Berkeley, California 94720-1460,USA. jellman@uclink.berkeley.edu
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Ellman
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Owens
authors.forename: Tony P
authors.initials: TP
authors.lastname: Tang