Hydrazine, propyl- → 2,4,6,7-Tetrahydro-3-(4-methylphenyl)-7-[(4-methylphenyl)-methylene]-1-propylthiopyrano[4,3-c]pyrazole

Participants

Reaction Steps

A mixture of tetrahydro-3,5-bis-(4-methylphenylmethylene)-4H-thiopyran-4-one (6.7 g, 20 mmole) and n-propylhydrazine (1.6 g, 22 mmole) in methanol (250 ml) is heated at reflux temperature for 5 hours, then cooled overnight. The pale yellow precipitate is collected by filtration. The filtrate is concentrated to about 50 ml and additional precipitate is again collected by filtration and combined with the previous batch to give 5.5 g of a crude product mixture.

Provenance & Evidence