METHOD FOR PREPARING 4-AMINO-4-PHENYLPIPERIDINES

摘要

The invention concerns a method for preparing a 4-amino-4-phénylpipéridine (I), wherein: R is hydrogen or a C>1<-C>3< alkyl group, characterised in that it consists in sequentially treating a protected 4-piperidone (II), wherein: Pr' represents a N-protecting group capable of being eliminated, firstly with an alkaline cyanide then with an amine ENHPr'' (III), wherein: E represents a group R' = C>1<-C>3< alkyl group or a N-protecting group and Pr'' is a N-protecting group, the group(s) capable of being eliminated in the same conditions as Pr', then in subjecting the resulting compound (IV) to a Grignard reaction with a phenylmagnesium halide, in eliminating the two or three protecting groups of the resulting compound (V) and in isolating the compound (I) either in the form of a free base which is transformed into one of its salts.