Synthesis of 3-Methyl-1<i>-</i>[2-(1-Piperidiny) Phenyl]-butyl Amine

Abstract

3-Methyl-1-[2-(1-piperidiny) phenyl]-butyl amine (1) is an important intermediate for synthesis of Repaglinide, a well-known oral medicine for diabetes. It has been reported that 1 could be obtained from o-flurobenzaldehyde undergoing Grignard reaction, oxidition, piperidine substitution, oximation and reduction. In the process of reduction, the oximate 3-methyl-1-[2-(1-piperidiny) phenyl]-butyl oxime (6) was reduced by NiCl2-NaBH4 with many impurities, difficult workup, low yield and a lot of environmental problems. Herein the environmental friendly catalytic hydrogenation with simple work-up was developed and the yield was of 95.5%. The structure of 1 has been confirmed by IR, 1H NMR, 13C NMR.