Patent ID: 6911544
Filing Date: 2005-06-28
Classification: C07D,Y02P

Abstract:
1. A process for preparing (S,S)-cis-2-phenyl-3-amino-piperidine which comprises: (a) reacting the amino acid, L-ornithine or salt having a protecting group on the amino group on the α-carbon and the amino group on the δ-carbon thereof, having the formula  with N-methoxy-N-methylamino or salt thereof under amide forming conditions to produce an amide of the formula in the S configuration (b) adding said amide to an effective amount of a Grignard reagent of the formula Ph MgX to form a ketone of the formula in the S configuration (c) selectively deprotecting the amino group on the δ carbon under conditions sufficient to cyclize said ketone to form a cyclic imine and reducing the resulting imine to form a product of the formula in the (S,S) configuration (d) removing the protecting group on the α-carbon to form said (S,S)-cis-2-phenyl-3-aminopiperidine, wherein P X is halide.