HCID 12888773, compound → HCID 135759095, compound

Participants

Reaction Steps

To 1-methyl-3-(4-chloro-2-nitroanilino)pyrazole-4-carbonitrile (16 g) stirred in ethanol (500 ml) was added a solution of anhydrous stannous chloride (33.1 g) in concentrated hydrochloric acid (176 ml). The mixture was heated under reflux for 2 hours, cooled, filtered and crystallised from methylated spirits (1 liter) to give the title compound as its hydrochloride salt m.p. >260° C. 2.0 g of the hydrochloride salt was partitioned between dilute ammonia solution and chloroform. The organic phase was washed with water, dried with magnesium sulphate, evaporated and the residue crystallised from chloroform-n-hexane to give the title compound as the free base m.p. 240° C.

Provenance & Evidence