Introduction: Laccase (benzenediol:oxygenoxidoreductase, EC 1.10.3.2), a multi-coppercontaining oxidoreductase enzyme, is one of the enzymes that is being studied as a biocatalyst in organic synthesis due to its ability to catalyze the oxidation of various substrates, specifically, phenols, o- and p-diphenols and lignin derivatives. This oxidation is accompanied by the reduction of dioxygen to water [1]. Sulfoxides and sulfones are valuable intermediates for the synthesis of fine chemicals and biologically active compounds [2]. Sulfonamides are widely used to treat many kinds of infection causedby bacteria and certain other microorganism [3].Methods/Experimental: Initially, in order to optimization of the reactions conditions, the effect of solvent, temperature, and amount of catalyst on the model reactions were investigated. Next, with optimal conditions in hand, the generality and the applicability of these methods were further examined. Finally, the products were characterized by IR, and NMR spectra.Results and Discussion: In continuation of our studies on the application of laccase as a biocatalyst in the aerobic oxidation of alcohols [4], herein, we have synthesized arylsulfonyl benzenediols and sulfonamide derivatives via aerobic oxidation of benzenediols and urazoles, respectively catalyzed by laccase in the presence of sodium arylsulfinates as nucleophile in phosphate buffer solution in good to high yields at room temperature. Also, the aerobic oxidation of sulfides to sulfoxides was investigated in the presence of catalytic amount of laccase and TEMPO as a mediator in Na-phosphate buffer (0.1M, pH 6)/MeCN (25:1) at room temperature. Conclusion: In this research, the synthesis of valuable compounds using O2 as an oxidant in the presence of laccase as green biocatalyst in the phosphate buffer solution as an environmentally friendly solvent at room temperature is described. The methods conform to several of the guiding principles of green chemistry. References
