Application of Non-Corrosive Acids in Three-Component, One-Pot Synthesis of Commercial Coumarin Dye

The efficiency of HZSM-5 Zeolite, tungestophosphoric acid (H3PW12O40) and tungestosililic acid (H4O40SiW12) were investigated in three-component, one-pot synthesis of coumarin dyes. These green and noncorrosive acids were highly efficient in synthesis of some coumarin dyes in excellent yield during concurrent formation of coumarin and benzimidazole or benzoxazole heterocycles (e.g. C. I. disperse yellow 232 as a commercial fluorescence dye was synthesized using tungestophosphoric acid in 45 minutes and %90 yield). Evaluations of the yields of products were studied in organic solvent (n-pentanol) and aqueous media and under solvent-free conditions considering the reaction times were studied as well. The results demonstrated that n-pentanol as an organic solvent was the best media for these preparations. Prog. Color Colorants Coat. 3(2010), 102-109. © Institute for Color Science and Technology.