Sodium Carbonate → 4-chloro-3-{3-[4-(4-fluorobenzoyl)-1-piperidinyl]-propyl}-1,3-dihydro-2H-benzimidazol-2-one

Participants

Reaction Conditions

Reaction Steps

A mixture of 4.4 parts of 3-(7-chloro-2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)propyl methanesulfonate, 3.4 parts of (4-fluorophenyl) (4-piperidinyl) methanone hydrochloride, 5 parts of sodium carbonate and 45 parts of N,N-dimethylformamide is stirred for 6 hours at 50-60° C. The reaction mixture is cooled and poured onto water. The product is extracted with 4-methyl-2-pentanone. The extract is dried, filtered and evaporated. The residue is purified by column-chromatography over silica gel using a mixture of trichloromethane and 10% of methanol as eluent. The pure fractions are collected and the eluent is evaporated. The residue is crystallized from a mixture of 4-methyl-2-pentanone and 2,2'-oxybispropane, yielding 1 part (18%) of 4-chloro-3-{3-[4-(4-fluorobenzoyl)-1-piperidinyl]-propyl}-1,3-dihydro-2H-benzimidazol-2-one; mp. 138° C.

Provenance & Evidence