Metal-organic frameworks as kinetic modulators for branched selectivity in hydroformylation.

Finding heterogeneous catalysts that are superior to homogeneous ones for selective catalytic transformations is a major challenge in catalysis. Here, we show how micropores in metal-organic frameworks (MOFs) push homogeneous catalytic reactions into kinetic regimes inaccessible under standard conditions. Such property allows branched selectivity up to 90% in the Co-catalysed hydroformylation of olefins without directing groups, not achievable with existing catalysts. This finding has a big potential in the production of aldehydes for the fine chemical industry. Monte Carlo and density functional theory simulations combined with kinetic models show that the micropores of MOFs with UMCM-1 and MOF-74 topologies increase the olefins density beyond neat conditions while partially preventing the adsorption of syngas leading to high branched selectivity. The easy experimental protocol and the chemical and structural flexibility of MOFs will attract the interest of the fine chemical industries towards the design of heterogeneous processes with exceptional selectivity

Recent Advances in Iridium-Catalysed Transfer Hydrogenation Reactions

This review focuses on the contributions of the last 5 years to the application of iridium complexes as homogeneous catalysts in transfer hydrogenation (TH) reactions. The reduction of carbonyls, imines, alkenes and alkynes is considered. The TH of unsaturated alkene-carbonyl substrates and heterocycles is particularly studied. Recent results on the reduction of CO2 are also included. Special attention is paid to THs performed in aqueous medium as well as to the development of TH in biological media. The employ of biomass-derived products as reagents or solvents in TH transformations is also reviewed. Finally, the proposed mechanisms for TH reactions are revised.Peer reviewe