Stereochemical features of oxidative mannich cyclizations of vinyl- and allyl-silane containing α-silyl-amines and -amides
作者:Seock-Kyu Khim、Xiaodong Wu、Patrick S. Mariano
DOI:10.1016/0040-4039(95)02263-5
日期:1996.1
Studies of the new oxidativeMannichcyclization reaction of α-silyl-amines and -amides demonstrate advantageous features of the process when applied to stereocontrolled hydropyridine syntheses.
A new route to functionalized piperidine and indolizidine scaffolds, based on the diastereoselective intramolecular Michael cyclization of vinyl-sulfinyl-containing amino alcohols 1-3, has been developed. Pyrolytic elimination of the resulting cycloadducts resulted in the regioselective formation of the corresponding tetrahydropyridines and indolizidines. The observed regiochemical course of this process can be explained mainly in terms of the steric bias imposed by the disposition of the arylsulfinyl group and the concerted syn mechanism accepted for this kind of elimination.