Recent development towards alkene hydroformylation catalysts integrating traditional homo- and heterogeneous catalysis

Abstract

Hydroformylation of alkenes, the most important homogenously catalyzed industrial process, has been widely used into the manufacture of aldehydes, and the resulting aldehydes are further converted into high value-added alcohols,...

Metal Phosphide: An Atypical Catalytic Site

“…Heterogeneous hydroformylation has attracted much attention due to the difficult separation of catalysts and products in homogeneous processes. , The hydroformylation reaction converts alkenes and syngas (CO/H 2 ) into corresponding aldehydes, where Rh δ+ is usually considered as the main active site. , Rhodium phosphides Rh 2 P were reported to exhibit high activity in ethylene, styrene, and 1-hexene hydroformylation reactions, which was attributed to the electronic modification of Rh sites by inorganic phosphorus in MPs (Figure A ). The X-ray photoelectron spectroscopy (XPS) and X-ray absorption near-edge structure (XANES) results demonstrated that Rh was positively charged between Rh(0) and Rh­(III) in Rh 2 P .…”

Composite Catalyst of Rh/POP-BINAPa&PPh3@ZSM-35(10) for the Heterogeneous Tandem Hydroformylation–Acetalization of Olefins

“…Therefore, the separation and recovery of both Rh/ligands and acid catalysts is an important issue to be considered when designing heterogeneous catalysts. As a kind of emerging support, the porous organic polymers (POPs) containing phosphorus ligands have been successfully used in the heterogeneous hydroformylation reaction owing to the high specific surface area and rich modifiability of phosphorus ligand moieties. − In addition, because of their outstanding stability, high adsorption capacity, confinement effects, and high surface areas, molecular sieves have been widely used in organic reactions as a solid acid catalyst. , Herein, based on the advantages of the two materials, we developed a composite catalyst consisting of Rh/POP-BINAPa&PPh 3 and ZSM-35(10) for the heterogeneous one-pot hydroformylation–acetalization of olefins (Scheme ). In the solid carrier, the BINAPa ligand with the strong π-acidity was used to achieve a highly reactive and selective hydroformylation process, and PPh 3 monomers could construct the porous framework with a high specific surface area, improving the stability and the loading capacity of Rh ion. , Compared with the previously reported heterogeneous catalyst, the composite catalyst of Rh/POP-BINAPa&PPh 3 @ZSM-35­(10) showed higher excellent activities (turnover number, TON up to 10,000) and regioselectivities ( l / b = 30.2–87.9).…”

Hydroformylation over polyoxometalates supported single-atom Rh catalysts

“…Despite their excellent activity and selectivity, traditional homogeneous rhodium catalysts are not easily recyclable and not sufficiently stable. Efforts have been made to immobilize rhodium complexes onto solid supports for easy separation, in which Rh species are still coordinated with organic ligands [3][4][5][6]. Alternatively, a phosphine ligand can be added in the postsynthesis stage to modulate Rh species on solid supports owing to its firm metal-ligand coordination [7].…”