Nano-TiCl4 /gama-Al2O3: an Efficient Heterogeneous Solid Acid Catalyst for Rapid and Solventless Synthesis of Azo dyes based on 2-Naphthol at Room Temperature

At the beginning of the new century, synthesis of organic compounds using grinding technique under solvent-free conditions has received much attention, as it provides manipulative simplicity, easier workup, and higher yields which match with the green chemistry protocol [1]. On the other side, more attention has been directed toward the application of solid acids in organic synthesis because such reagents not only simplify purification processes but also help prevent release of reaction residues into the environment [2].The reactions that are affected by the nano catalysts immobilized on the inert porous solid supports, have received significantposition in organic synthesis.The individual features of supported Lewis acids such as their ease of handling, enhance reaction rates, greater selectivity, and recoverability of catalysts make the use of supported Lewis acids attractive [3].In this work we wish to report diazotization of aromatic prime amines with NaNO2, TiCl4/gama-Al2O3 nano particle at room temperature and diazo coupling with 2-naphthol has developed a mild and convenient method for the synthesis of azo dyes under solvent-free conditions at room temperatureFigure 1