Sub-nanometer Rh1+ oxide in zeolites catalyzes the hydroformylation reaction under counterbalancing cation control

Summary Rhodium (Rh)-supported zeolites are intensively studied as solid catalysts for the industrial hydroformylation reaction in order to replace the currently used soluble Rh catalysts. Here, we show that the counterbalancing cations of the zeolite, inherent to these aluminosilicates, significantly impact on the catalytic activity and selectivity of the hydroformylation reaction when sub-nanometer Rh¹⁺-oxide species, generated inside the zeolite after incorporation and calcination of simple Rh species, are employed as catalytic sites. A Rh-supported faujasitic structure-activity relationship is thus provided for the hydroformylation reaction, perhaps extensible to other reactions. The ligand-free Rh zeolites can now be rationally chosen for one or another alkene reactant and also to perform one-pot hydroformylation/acid catalyzed reactions, thus opening new ways to design solid catalysts for these paramount reactions.