A new family of dinuclear chromium complexes bearing thioether-triphenolate ligands has been developed for the cycloaddition of CO2 with epoxides. The catalytic systems resulting from the combination of complexes 1-3 with tetrabutylammonium chloride (TBAC) show high activity and selectivity for the synthesis of cyclic carbonates with a broad range of substrates including terminal and internal epoxides. Notably, in the case of epichlorohydrin, a TOF up to 4650 h-1 (120 °C, 2 MPa) was recorded, showing one of the highest activity for chromium complexes. In the case of internal epoxides, the reaction proceeds with the retention of the substrate configuration highlighting that the mechanism proceeds through two consecutive SN2 reactions. © 2022 Elsevier Ltd.
New dinuclear chromium complexes supported by thioether-triphenolate ligands as active catalysts for the cycloaddition of CO2to epoxides
Contento, I.;Lamparelli, D. H.;Buonerba, A.;Grassi, A.;Capacchione, C.
2022-01-01
Abstract
A new family of dinuclear chromium complexes bearing thioether-triphenolate ligands has been developed for the cycloaddition of CO2 with epoxides. The catalytic systems resulting from the combination of complexes 1-3 with tetrabutylammonium chloride (TBAC) show high activity and selectivity for the synthesis of cyclic carbonates with a broad range of substrates including terminal and internal epoxides. Notably, in the case of epichlorohydrin, a TOF up to 4650 h-1 (120 °C, 2 MPa) was recorded, showing one of the highest activity for chromium complexes. In the case of internal epoxides, the reaction proceeds with the retention of the substrate configuration highlighting that the mechanism proceeds through two consecutive SN2 reactions. © 2022 Elsevier Ltd.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
