Zirconia-Based Solid Acids: Green and Heterogeneous Catalysts for Organic Synthesis

This review highlights the application of sulfated, molybdated and tungstated zirconia solid acid catalysts, and their modified forms for variety of organic synthesis and transformation reactions in the liquid phase. Most of these catalysts offer significant improvements in various organic reactions with regard to the yield of products, simplicity in the operation, reusability of the catalysts and green features by avoiding toxic conventional catalysts. Preparation of various zirconia-based solid acid catalysts has been briefly described. Characterization of these catalysts by different techniques has also been presented. Most of these catalysts are highly promising for numerous organic reactions in the liquid phase which include condensation, isomerization, esterification and transesterification, muticomponent reactions and so on.