Hydrazine hydrate (1:1) → HCID 178462998, compound

Participants

Reaction Steps

A mixture of 11.0 g. of 4-chloro-1-ethyl-10,11-dihydrobenzo[4,5]cyclohepta[1,2-b]pyrazolo[4,3-e]pyridin5(1H)one (0.035 mol.), 4.5 g. of hydrazine hydrate 98% (0.09 mol.) and 125 ml. of abs. ethanol is refluxed for 3 hours with stirring. Then the reaction solution is filtered while hot and allowed to crystallize in a refrigerator. The crystallized 2,5,7,8-tetrahydro-5-ethyl-1,2,4,5,6-pentaazabenzo[6,7]cyclohepta[1,2,3-cd]-as-indacene which is filtered off, washed with alcohol and ether, melts at 229°-231°. Evaporation of the mother liquor to dryness and treatment with water yields a further crop of 1.9 g. of the product. Total yield 97%. Recrystallization from ethanol elevates the melting point to 230°-232°.

Provenance & Evidence