(4-Chlorophenyl)hydrazine → HCID 19016808, compound

Participants

Reaction Steps

A mixture of 2.4 g of 2-bromo-4-oxo-5,6-dihydro-4H-thieno[2,3-b]thiopyran-5-acetic acid and 1.3 g of 4-chlorophenylhydrazine in 40 ml of ethanol is refluxed under heating for 14 hours. After cooling, the precipitated crystals are collected by filtration, washed with ethanol and then recrystallized from a mixed solvent of chloroform and ethanol to give 1.3 g of 8-bromo-2-(4-chlorophenyl)-4a,5-dihydro-2H-thieno[2',3':2,3]thiopyrano[4,5-c]pyridazin-3(4H)-one as pale brown crystals, melting at 169°-170° C.

Provenance & Evidence