Stereochemical course of the reductive spiroannulations of N-Boc and N-benzyl 2-cyanopiperidines
作者:Scott A. Wolckenhauer、Scott D. Rychnovsky
DOI:10.1016/j.tet.2005.01.099
日期:2005.3
The stereochemical outcome of spiroannulations of N-protected 2-lithiopiperidines (generated by lithium di-tert-butyl biphenylide (LiDBB) mediated reductive lithiation of 2-cyanopiperidines) was investigated using deuterium labeled side-chains containing phosphate leaving groups. High stereoselectivity was observed when benzyl (Bn) protected 2-cyanopiperidines were employed, while tert-butoxycarbonyl