Benzo[4,5]imidazo[2,1-a]phthalazines: I. substituted o-nitrophenylhydrazines in the synthesis of phthalazin-1(2H)-ones
摘要:
Efficient cyclization procedure was developed for 2-nitro-, 2,4-dinitro-, 2-nitro-5-chloro-, and 4,5-dichloro-2-nitrophenylhydrazines with 2-acylbenzoic acids by heating the reagents in a mixture of of concentrated sulfuric acid and ethanol. A series of new phthalazin-1-ones was obtained with a substituted 2-nitrophenyl group in the position 2 and various substituents in the position 4.