Reactive dyes for cellulose. Concurrent methoxide‐hydroxide reactions of triazinyl reactive systems: a model system for assessment of potential fixation efficiency

Abstract

A series of triazinyl reactive dyes, identical in all respects but for the leaving group, has been synthesised. The rate of hydrolysis of each member of the series, i.e. fluoro, chloro, sulpho and DABCO derivatives, has been determined. The corresponding nicotinic acid compound could not be included in the study as it did not yield the expected hydroxytriazine in dilute sodium carbonate solution. Each dye has been added, in turn, to a methanol‐water solution in the presence of base and the chemical selectivity to methoxide attack determined from the product ratio. Measurements were made at 40°C and under conditions of equal reactivity to hydroxide ion, as determined from Arrhenius plots. The selectivity results are in agreement with empirical observations, made over more than 30 years, for the fixation efficiency to cellulose of dyes carrying these reactive groups.