Abstract In contrast to heterogeneous network frameworks (e.g., covalent organic frameworks and metal-organic frameworks) and porous organic polymers, porous organic cages (POCs) are soluble molecules in common organic solvents that provide significant potential for homogeneous catalysis. Herein, we report a triphenylphosphine-derived quasi-porous organic cage (denoted as POC-DICP) as an efficient organic molecular cage ligand for Rh/PPh 3 system-catalyzed homogeneous hydroformylation reactions. POC-DICP not only displays enhanced hydroformylation selectivity (aldehyde selectivity as high as 97% and a linear-to-branch ratio as high as 1.89) but can also be recovered and reused via a simple precipitation method in homogeneous reaction systems. We speculate that the reason for the high activity and good selectivity is the favorable geometry (cone angle = 123.88°) and electronic effect (P site is relatively electron-deficient) of POC-DICP, which were also demonstrated by density functional theory calculations and X-ray absorption fine-structure characterization.

Hydroformylation; Triphenylphosphine; Porous organic cages; Chemical selectivity; Linear-regioselectivity

Dalian Institute of Chemical Physics,Chinese Academy of Sciences