Engineering atomic rhodium sites on conjugated porous monophosphine polymers for superior heterogeneously catalytic hydroformylation and hydrosilylation of alkenes

Efficient rhodium-based heterogeneous catalysts with exceptional catalytic activity and efficient atom utilization are crucial for converting alkene feedstocks into valuable fine chemicals. Phosphine-functionalized porous organic polymers (POP) have emerged as promising supports for rhodium catalysts. Herein, we synthesize atomic Rh sites coordinated on conjugated porous monophosphine polymers (Rh@POP) for superior heterogeneously catalytic hydroformylation and hydrosilylation of alkenes. The Rh@POP features triphenyl phosphine-Rh coordination and alkenyl nitrile conjugation. A 2.3 % Rh@POP catalyst (Rh mass loading 2.3 wt%) exhibits exceptional activity and selectivity in mild hydroformylation and hydrosilylation of alkenes. The turnover frequency (TOF) reaches 5549 h- 1 in hydroformylation of 1-octene. Remarkably, this catalyst maintains consistent reactivity over 6 recycling runs. The high dispersion of rhodium atoms, phosphine coordination, and alkenyl nitrile-containing POP framework contribute to its outstanding performance. This study offers insights into designing single-atom heterogeneous catalysts with high activity and recyclability, effectively combining the merits of homogeneous and heterogeneous catalysis.