Isopropanol → HCID 13792109, compound

Participants

Reaction Steps

A mixture of 26 parts of ethyl 4-[1,3-dihydro-2-oxo-5-(trifluoromethyl)-2H-benzimidazol-1-yl]-1-piperidinecarboxylate, 30 parts of potassium hydroxide, 176 parts of 2-propanol and 4 parts of water is stirred and refluxed for 20 hours. The reaction mixture is evaporated. The residue is dissolved in water, acidified with a concentrated hydrochloric acid solution, while cooling, and alkalized with a concentrated ammonium hydroxide solution. The product is extracted with trichloromethane. The extract is washed with water, dried, filtered and evaporated. The residue is crystallized from a mixture of 2,2'-oxybispropane and 2-propanol. The product is filtered off and dried, yielding 1,3-dihydro-1-(4-piperidinyl)-5-(trifluoromethyl)-2H-benzimidazol-2-one; mp. 198° C.

Provenance & Evidence