Synthetic applications of 2-aryl-4-piperidones. X Synthesis of 3-aminopiperidines, potential substance P antagonists

Abstract A general method is described for the synthesis of 3-aminopiperidines from 4-piperidones based on a KOEt treatment of the tosylate of the corresponding oximes (Neber rearrangement). The procedure is applied to the synthesis of N -benzyl-3-amino-4,4-diethoxypiperidine ( 13 ), ( R )- N -(2-hydroxy-1-phenyl)ethyl analogues 18 , and 2-phenyl derivatives 27–28 . The methoxybenzylation of the primary amino group of these aminopiperidines leads to a series of potential substance P antagonists.