2-Cyano-.DELTA.3-piperideines. 12. Stereochemistry of formation of N-benzyl-2-cyano-.DELTA.3-piperideines and facile isomerization on alumina to 2-cyano-.DELTA.4-piperideines. A potentially general route to the synthesis of 2,6-disubstituted piperidine alkaloids
作者:Martine Bonin、Jose Ricardo Romero、David S. Grierson、Henri Philippe Husson
DOI:10.1021/jo00187a018
日期:1984.6
Stereoselective synthesis of 26-disubstituted piperidine alkaloids via TiCl4 induced iminium ion cyclization of α-cyanoamines
The stereoselective cyclization of an α-cyanoamine containing a vinyl group induced by TiCl4 in a methylene chloride solution, produces cis 2,6-dialkylpiperidine; whereas a similar reaction of an α-cyanoamine containing a silyl substituted vinyl group gave the corresponding trans isomer only.