Environmentally friendly efficient synthesis and mechanism of Dyes Derived from 2-Hydroxy benzoic acids on Clays and Zeolites

The formation of diazotizing reagent starts with protonation of nitrous acid under strongly acidic conditions, and azo coupling carried out at low temperature in the presence of nucleophilic coupling components, the reactivity of a nucleophilic substrate increases with increasing basicity phenolates and amines [1]. The acidic and basic effluents from the laboratory and industry produce permanent damage to the environment and disturb the ecological balance [2]. Clays have long been used as acidic catalysts and existence of both Lewis and Bronsted acid sites. These clays are low-cost, widely available materials, and synthetic organic chemists have largely used them in a variety of acid-catalysed reactions [3]. Nowadays more and more heterogeneous Bronsted acids, e.g. zeolites are utilized Zeolites are preferred from an economical perspective as well as from an ecological viewpoint, the excellent catalytic abilities are due to the presence of Bronsted and Lewis acid centers in the zeolite structure [4]. Pharmacological effects and biotransformation pathways of salicylic acid and its derivatives are well known [5–8], More attention has been recently paid to the ability of salycilates to inhibit platelet aggregation. A recent patent reported that benzoic acid derivatives have good anti-tumor properties, their activity being related to novel synergistic compositions that selectively control tumor tissue [9]. As part of our ongoing research program [10, 11], here in we describe a new process for the synthesis of new dyes containing 4-sulfonyl azide benzenediazonium salt, salicylic acid and 2-dihydroxy benzoic acid derivatives as the coupling component over eco-friendly clay catalysts, Zeolites are described.