Abstract

COMPARATIVE STUDY OF SYNTHESIS OF 2, 4, 5-TRIARYL SUBSTITUTED IMIDAZOLES UNDER SOLVENT FREE CONDITIONS USING DIFFERENT LEWIS ACIDS AS CATALYSTS

Satish Patil*, Jayesh Patil and Sadanand Dharap

Abstract

A range of 2, 4, 5-triaryl substituted imidazoles have been synthesized in very good yields under solvent-free conditions by grinding 1, 2- diketone, aromatic aldehydes and ammonium acetate in the presence of I2, NaH2PO4 and SnCl2.2H20 as catalysts. Optimization of reaction conditions were carried out using different amount of catalysts. 10 mol% catalysts were found to be sufficient catalyze the reaction with high yield. Rate of synthesis of imidazoles and yield of the products were found to be directly proportional to the acidity of Lewis acid catalysts. The short reaction time, green reaction, and simple operation make this protocol practical and economically attractive. Effectiveness of catalysts was found to be of the order of SnCl2.2H2O>NaH2PO4>I2.

Keywords: Triaryl imidazoles, Lewis acids, catalysts, solvent free.