Synergistic Effect of Bronsted and Lewis Acid Amounts on One‐Pot Synthesis of Aminoxazole by Propargylation and Cycloisomerization

Abstract

One pot synthesis of aminoxazoles through propargylation and cycloisomerization reaction requires both Bronsted and Lewis acid amounts. The variation in any one of the acid amounts or pore volume upon loading of oxometalates or metal chlorides on gamma alumina causes alteration in the product distribution. The synergistic effect of Bronsted to Lewis (B/L) acid amounts ratio gives better yield. The combination of pore characteristics and acidity provides an idea about the approach of reaction intermediate to both acid sites within the pore giving good selectivity of final product. Among the three factors, either the increase or decrease in one of the acid amounts or pore volume alters the product distribution. The combined effect of B/L ratio and pore volume contributes better yield of final product aminoxazole. It is also evident that, the better correlation was obtained by volume accessibility factors.