Anthraquinone dyes. Part III. Nitration of toluoylbenzoic acid and cyclisation of the corresponding amino-acids to amino-derivatives of 2-methylanthraquinone

Abstract

In agreement with the calculated reactivity of 2-(4-methyl-3-nitrobenzoyl)benzoic acid based on sigma constants, nitration gives a mixture of 2-(3,5-dinitrobenzoyl)-, 2-(4-methyl-3-nitrobenzoyl)-4-nitro-, and 2-(4-methyl-3-nitrobenzoyl)-5-nitro-benzoic acids. Further nitration yields a mixture of 2-(4-methyl-3,5-dinitrobenzoyl)-4-, and -5-nitrobenzoic acids. The acids were isolated and identified in the form of the corresponding diamino-and triamino-derivatives of methylanthraquinone.