The Versatility of Immobilized Mo Complexes in Organic Transformations - Epoxidation and Metathesis Reactions

Abstract

In most of the chemical and pharmaceutical industrial processes at least one catalytic step is essential during their synthesis. Catalysts speed up chemical reactions but can be recovered unchanged at the end of the reaction. In this respect, heterogeneous catalysts surpass their homogeneous congeners by offering better recyclability as well as an easier separation from the reaction medium. Increasing research in recent years has led to new catalysts capable of directing a given reaction towards a specific product as well as allowing reactions to be carried out at lower temperatures and pressures with higher selectivity towards the desired product.Due to their relevance in biological processes, Mo-catalyzed reactions have attracted considerable interest. In this context, the present work aims at reviewing some of the most recent advances on heterogenized Mo-species in mesoporous materials. In this way, two of the most relevant reactions using olefins as substrates-epoxidation and metathesis where Mo is a major player are assessed. The former is relevant because epoxides are important intermediaries in industry, while the latter is quite significant since without it many organic transformations would simply be impossible.Scheme 2. Preparation of heterogeneous catalysts by the co-condensation method, using PMO supports [46][47][48][49][50][51][52][53][54].