(1) Butlerov Institute of Chemistry, Kazan State University, ul. Kremlevskaya 18, Kazan, 420008, Tatarstan, Russia;(2) Arbuzov Institute of Organic and Physical Chemistry, ul. Arbuzova 8, Kazan, 420029, Tatarstan, Russia
Abstract:
It was found that benzoic acid hydrazides rapidly and quantitatively react with electrogenerated chlorine and bromine under the conditions of galvanostatic coulometry. Benzoic acid hydrazides were determined in model solutions. A good precision (RSD varied from 1 to 6%) allowed coulometry to be applied to the determination of isonicotinic acid hydrazide in isoniazid tablets and isonicotinic acid 3-methoxy-4-hydroxybenzylidenehydrazide in phthivazid tablets.