Semicarbazide hydrochloride → 2,3-Dihydroxy-naphthaldehyde semicarbazone

Participants

Reaction Conditions

Reaction Steps

86.0 g of semicarbazide hydrochloride dissolved in 500 ml of water and 103 g of sodium acetate (CH3COONa.3H2O) were placed in a 2.5 l sulfonation flask equipped with stirrer, thermometer and dropping funnel. At an internal temperature of 40°-50° C., there was added dropwise a solution of 138.4 g of 2,3-dihydroxy-naphthaldehyde in 1000 ml of methanol. The mixture was stirred at 40°-50° C. for 1 hour and then, after adding 2 l of water, cooled to 10° C. and suction filtered. The material on the suction filter was back-washed thoroughly with water and dried at 60° C. in vacuo. Recrystallization from glacial acetic acid gave 131.9 g (73.1% of theory) of 2,3-dihydroxy-naphthaldehyde semicarbazone of melting point 210°-215° C.

Provenance & Evidence