Heterogeneous Bisphosphine Ligand-Encapsulated Rh Catalysts for Heterogeneous Hydroformylation of Alkenes with CO₂

The development of convenient and effective heterogeneous catalysts for the hydroformylation of alkenes with CO2 remains a challenge. Herein, we describe the encapsulation of single-atom Rh catalysts in a porous heterogeneous bisphosphine ligand for the hydroformylation of aromatic and aliphatic alkenes with CO2. The optimal catalyst Rh@Dppe&PPh3 shows excellent catalytic activity for alkenes/CO2 hydroformylation with good conversion (91%) and high yield (89%), which is comparable to homogeneous catalysts. The catalysts are characterized by different analysis techniques such as Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption/desorption, thermogravimetry (TG), and inductively coupled plasma atomic emission spectroscopy (ICP-AES). Moreover, the catalyst can be reused for at least three successive cycles without obvious loss of activity. This discovery provides a promising pathway for the conversion of CO2 to value-added chemicals.