Asymmetric Synthesis of Tetrahydro-β-carboline Alkaloids Employing Ellman’s Chiral Auxiliary

Abstract

A stereoselective synthesis of tetrahydro-β-carboline alkaloids has been accomplished using Ellman’s sulfinamide as a chiral source. This is the first report on the synthesis of chiral tetrahydro-β-carboline natural products using <i>tert</i>-butanesulfinamide through haloamide cyclization. Similarly, the synthesis of an indolizino[8,7-<i>b</i>]indole alkaloid, (–)-harmicine, has been achieved by means of allylation of an <i>N</i>-sulfinylimine, hydroboration, and S_N2 substitution.