Intermediates and dyestuffs for synthetic fibres. Part I. Arylaminonitropyridines

Abstract

Condensation of 2-chloro-3-nitropyridine-2-chloro-5-nitropyridine and 4-chloro-3-nitropyridine with aniline, o-, m-, and p-anisidine, o-, m-, and p-fluoroaniline and with p-aminophenyl methyl sulphone gives the corresponding arylaminonitropyridines in good yield. These compounds have an ultraviolet absorption band in the 350–420 mµ region, characteristic of the contribution of a “quinonoid” charge-transfer form to the excited state. The position of this band is influenced more by substituents in the nitrated ring than by those in the un-nitrated ring. NH stretching frequencies in the infrared are also recorded, the position of which can be correlated with the conclusions derived from the ultraviolet spectra.