Diphosgene → HCID 14053649, compound

Participants

Reaction Steps

To a solution of 2-(2-fluoro-5-nitrophenyl)1,2,4,5,6,7-hexahydro-3H-indazol-3-one (66.87 g) in toluene (125 ml) and 1,2-dichloroethane (175 ml), there was added trichloromethyl chloroformate (71.57 g), and the resultant mixture was allowed to react in an autoclave at a temperature of 120° to 130° C. under a pressure of 25 kg/cm2, for 3 hours. After cooling, the solvent was removed by distillation. The residue was purified by silica gel column chromatography using a mixture of ethyl acetate and n-hexane (1 : 6) as an eluent to give 3-chloro-2-(2-fluoro-5-nitrophenyl)-4,5,6,7-tetrahydro-2H-indazole. m.p., 109.1° C.

Provenance & Evidence