(769c) Pechmann Condensation of Resorcinol with Ethyl Acetoacetate Over a Novel Highly Superacidic Sulfated Zirconia

A novel zirconia-based catalyst, with high sulfur content (15% w/w) and preservation of the tetragonal phase of zirconia was synthesized for the first time via solution combustion synthesis approach. Such high sulfur content with preservation of tetragonal phase has not been reported so far. The catalyst synthesis parameters were optimized using a probe reaction of Friedel Craft’s alkylation. The optimized catalysts, namely, fuel lean sulfated zirconia (FLSZ) and fuel rich sulfated zirconia (FRSZ) were characterized by XRD, FTIR, TPD, EDAX, SEM, and BET surface area and pore size analysis. Further, the activity and stability of FLSZ was tested using Pechmann condensation reaction between resorcinol and ethyl acetoacetate to produce selectively 7- hydroxy 4-methyl coumarin. A complete theoretical and experimental analysis is presented and a kinetic model is developed for this reaction. The model explains the experimental data well. The characterization and reaction studies show that combustion synthesized sulfated zirconia exhibits higher superacidity relative to the conventional sulfated zirconia catalyst.