Asymmetric Pictet-Spengler reactions with (R)-N-p-tolylsulfinyl-3,4-dimethoxyphenylethyl amine proceeded with high diastereo selectivity. Starting from the commercially available (R)- and (S)-Andersen reagents a highly efficient route to (+)- and (-)-salsolidine and related tetrahydroisoquinolines was developed. (C) 2001 Elsevier Science Ltd. All rights reserved.
A Novel Straightforward Synthesis of Enantiopure Tetrahydroisoquinoline Alkaloids
作者:Rafael Pedrosa、Celia Andrés、Jesús M. Iglesias
DOI:10.1021/jo001397s
日期:2001.1.1
formation of chiral 2,3-substituted perhydro-1,3-benzoxazines derivedfrom (-)-8-aminomenthol, (ii) diastereoselectiveintramolecular ring opening of the N,O-acetal moiety by an arylmetal generated from the substituent at the nitrogen atom in the perhydrobenzoxazine ring, and (iii) removal of the chiral auxiliary appendage. The starting perhydrobenzoxazines are easily prepared from (-)-8-aminomenthol and two