Hydrochloric Acid → HCID 20385596, compound

Participants

Reaction Steps

A solution of 98.5 parts of 1-[3-{4-[(4-chloro-2-nitrophenyl)amino]-1-piperidinyl}propyl]-1,3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-one in 360 parts of methylbenzene is acidfied with 2-propanol, previously saturated with gaseous hydrogen chloride. After boiling for a while, an oil precipitates. The supernatant phase is decanted and the residual oil is suspended in water. The suspension is alkalized with a concentrated ammonium hydroxide solution. The product is extracted with methylbenzene. The extract is dried, filtered and evaporated. The residue is crystallized from 4-methyl-2-pentanone. The product is filtered off and dried, yielding 68 parts (75.5%) of 1-[3-{4-[(4-chloro-2-nitrophenyl)amino]-1-piperidinyl}-propyl]-1,3-dihydro-2H-benzimidazol-2-one. A mixture of 21.5 parts of 1-]3-{4-[(4-chloro-2-nitrophenyl)-amino]-1-piperidinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one and 240 parts of methanol is hydrogenated at normal pressure and at room temperature with 5 parts of Raney-nickel catalyst. After the calculated amount of hydrogen is taken up, the catalyst is filtered off and the filtrate is evaporated, yielding 20 parts (100%) of 1-[3-{4-[(2-amino-4chlorophenyl)amino]-1-piperidinyl}propyl]-1,3-dihydro-2H-benzimidazol-2-one as a residue.

Provenance & Evidence