(4-Chlorophenyl)hydrazine → HCID 19016812, compound

Participants

Reaction Steps

A mixture of 3.0 g of 2-methyl-4-oxo-5,6-dihydro-4H-thieno[2,3-b]thiopyran-5-acetic acid and 2.0 g of 4-chlorophenylhydrazine in 50 ml of ethanol is refluxed under heating for 9 hours. After cooling, the mixture is concentrated under reduced pressure, the residue is subjected to column chromatography on silica gel and eluted with chloroform. The crystals obtained from the fraction are recrystallized from a mixed solvent of chloroform and ethanol to give 2.0 g of 2-(4-chlorophenyl)-8-methyl-4a,5-dihydro-2H-thieno[2',3':2,3]thiopyrano[4,5-c]pyridazin-3(4H)-one as pale brown crystals, melting at 142°-144° C.

Provenance & Evidence