Trifluoroacetic acid → 4-(1-(4-fluorobenzyl)-1H-benzimidazole-2-carbonyl)piperidine

Participants

Reaction Steps

With stirring, trifluoroacetic acid (10 ml) was added to 4-[1-[(4-fluorophenyl)methyl]-1H-benzimidazol-2- yl]carbonyl-1-piperidinecarboxylic acid, 1,1-dimethylethyl ester (1.65 g, 3.77×10-3 mole). After 30 minutes the reaction was cooled in an ice bath and ether (150 ml) was added. The flask was stoppered and placed in the refrigerator. After several hours, the solid was collected by filtration, washed with Et2O, and dried by suction. Crystallization from ethanol/ether afforded [1-[(4-fluorophenyl)methyl]-1H-benzimidazol-2-yl]-4-piperidinylmethanone, mono (trifluoroacetate) as colorless needles: 1.45 g (84%), m.p. 213-215° C. (decomp).

Provenance & Evidence