Exploration of Stable and Phosphine Ligand Free Heterogeneous Catalyst for Ethylene Hydroformylation

The development of highly active, stable and phosphine ligand free heterogeneous catalyst for hydroformylation reaction remains an open challenge. Herein, we developed highly active, stable and phosphine ligand free heterogeneous catalyst for ethylene hydroformylation reaction by replacing single strongly coordinating phosphine ligand with multiple weakly coordinating oxygen functional groups on the activated carbon surface. Applying of the typical Rh/C-3 catalyst in hydroformylation of ethylene affords unprecedented turnover frequencies (TOFs) up to 57 889/h. Besides, the Rh/C-3 catalyst exhibited substantially improved stability in the hydroformylation of ethylene in a fixed-bed reactor (at least 2500 h). For the first time, detailed characterizations revealed that lactone group (-CO₂-) on the surface of activated carbon might play a crucial role to gain this catalyst with remarkable activity and stability, which facilitate the homogeneous dispersion and stability of Rh nanoparticles. This work provides a general guidance for the design of highly active, stable and phosphine ligand free heterogeneous catalysts for hydroformylation of olefins.