Transesterification is an important organic reaction that can be used to synthesize various intermediates in the synthesis of complex natural products, pheromones, polymers and paint additives. Its value has been considerably enhanced by its use as a key step in the manufacture of biodiesel, one of the more environmentally friendly and sustainable fuels we have available today. Transesterification reactions mostly proceed using expensive homogeneous organometallic catalysts, strong acids and soluble bases, none of which is ideal from a green chemistry perspective. They are incompatible to the modern synthetic industrial chemistry that desires to be highly efficient, selective, ecofriendly and preferably catalytic.

One of the most important current topics in catalysis is the development of efficient and environmentally friendly polymer supported catalyst for carrying out various organic reactions for industrial purposes. In spite of the high activity, the application of homogeneous catalysts has declined in past years due to several problems, particularly the decomposition or degradation of the catalyst following a variety of pathways such as auto-oxidation, ligand decomposition and separation. Therefore, one of the challenges in green chemistry is to develop highly selective heterogenized homogeneous catalysts. Immobilization of molecular homogeneous catalysts is a promising approach that offers a dual advantage of selectivity and activity of the homogeneous catalyst as well as the ease of separation and re-usability of the heterogeneous catalyst.

In the present work, we have carried out the immobilization of zinc salicyaldimine complex on silica and evaluated its catalytic activity for transesterifcation.

This new approach to immobilization of complexes exhibits promise in tailoring synthesis of highly active, stable and reusable catalysts for specialized reactions.