Metal-organic frameworks as heterogeneous catalysts in liquid phase reactions: why are they so exceptional?
Metal-Organic Frameworks (MOFs) are crystalline porous materials consisting of metal ions or clusters of metal ions coordinated to rigid organic linkers to form one-, two-, or three-dimensional pore system. In the present Perspective, we discuss the interest of MOFs in heterogeneous catalysis that derive from unique features present in these materials related with high porosity, large surface area, high content of transition metals and the presence of coordinatively unsaturated sites. After presenting general properties of MOFs, different reaction types in which the use of MOFs can be advantageous with respect to current microporous catalysts are briefly reviewed making emphasis on aerobic oxidations, reductions, cross-coupling reactions and condensation of carbonyl groups. This article includes also a short section on our outlook for future developments in this field.