1-BOC-4-CYANO-4-(2,4-DIFLUOROPHENYL)-PIPERIDINE synthesis

Yield:216311-12-5 0.720 g (62%)

Reaction Conditions:

with NaH in N,N-dimethyl-formamide;

Steps:

96 4-Cyano-4-(2,4-difluorophenyl)-piperidine-1-carboxylic acid tert-butyl ester.

4-Cyano-4-(2,4-difluorophenyl)-piperidine-1-carboxylic acid tert-butyl ester. To bis(2-chloroethyl)-carbamic acid tert-butyl ester (1.0 g, 3.8 mmol) and 2,4-difluorophenyl acetonitrile (0.581 g, 3.8 mmol) in DMF (35 ml), NaH (95%) (0.258 g, 9.68 mmol) was added in one batch at 0° C. The solution was stirred for 10 minutes at room temperature. When foaming subsided, the solution was heated at 60° C. for 24 hours. It was then quenched with water at 0° C. and concentrated. The residue was extracted with ethyl acetate (25 mL) and washed three times with water (15 mL). The organic layer was dried over sodium sulfate, filtered and concentrated. Purification by column chromatography (hexane:ethyl acetate 4:1) yielded 0.720 g (62%) of the product as a syrup.

References:

US6245773,2001,B1