Phthalazineおよび関連化合物の研究 (第8報)

1(2H)-Phthalazone類のニトロ化について

抄録

Nitration of 1(2H)-phthalazone (XIV) and its 4-substituted derivatives was carried out with potassium nitrate and conc. sulfuric acid. XIV formed 5-nitro compound and a minute amount of 8-nitro compound. 4-Methyl-1(2H)-phthalazone (I) chiefly formed 8-nitro compound and a small amount of 5-nitro compound. Nitration of 4-oxo-3, 4-dihydro-1-phthalazinecarboxylic acid (XXII) in the cold gave 8- and 6-nitro compounds while nitration of XXII with heating gave 6-nitro compound and decarboxylated 4, 5-dinitro-1(2H)-phthalazone (XXVIII), which is also obtained by further nitration of 5-nitro-1(2H)-phthalazone (XV) and 5-nitro-4-oxo-3, 4-dihydro-1-phthalazinecarboxylic acid (XIX). The position of nitro group in the above compounds was determined by comparison and identification with the corresponding compounds synthesized by another route (cf. Charts 1-3).