N-Methylethylenediamine → 9,10-Anthracenedione, 1,4-bis((2-(methylamino)ethyl)amino)- (9CI)

Participants

Reaction Conditions

Reaction Steps

A mixture of 2.4 g. of leuco-quinizarin and 25 g. of de-aerated N-methylethylenediamine is heated at 50° C. with stirring under nitrogen for one hour. Heating at 50° C. is continued as air is bubbled into the mixture for 40 minutes. The mixture is evaporated to dryness, then re-evaporated twice from 25 ml. portions of ethanol. Crystallization of the residue from ethanol-ether at -70° C. gives 2.32 g. of crude solid which is recrystallized twice from carbon tetrachloride giving 1.92 g. of the desired product as dark blue crystals, mp. 131°-132° C.

Provenance & Evidence