Catalysis in Confined Spaces of Metal Organic Frameworks

Abstract Compared to homogeneous catalysis, heterogeneous catalysis can achieve product selectivity due to spatial constraints and differences in molecular dimensions of substrates and products by performing the reaction in a confined space. Shape selectivity for substrates, products or transition states is a well‐established phenomenon observed in porous inorganic solids like zeolites with considerable impact in petrochemistry. More recently, metal organic frameworks (MOFs) have emerged as heterogeneous solid catalysts for a broad range of organic reactions due to their unique properties of large surface area, tuneable pore volume and high density of sites. The present mini‐review aims to describe the current evidences showing MOFs as shape‐selective catalysts. After a brief introduction on the concept, types and examples of shape‐selectivity, the available data on MOFs as shape‐selective catalysts have been organized according the nature of active sites promoting the reaction, starting from metal nodes as Lewis acid sites and commenting examples of encapsulated metal nanoparticles (NPs) and molecular guests as centers in various reactions such as addition to carbonyl compounds, hydrogenations, oxidations and oxidative dehydrogenations. The final section provides our view on the current achievements and prospective for future developments in the field.