Chiral Mn(III) salen complexes immobilized directly on pyrolytic waste tire char for asymmetric epoxidation of unfunctionalized olefins

Two kinds of chiral Mn(III) salen complexes were synthesized and directly immobilized on pyrolytic waste tire char (PWTC) without modification of any organosilicon, which was an economic support, having rich oxy functionalized groups inherently. The as-prepared heterogeneous catalysts were characterized by X-ray photoelectron spectra (XPS), N2 sorption, Fourier transform infrared spectra (FT-IR) and thermogravimetric analysis (TG), and possessed of good catalytic performance in asymmetric epoxidation of unfunctionalized olefins. They obtained higher enantiomeric excess (ee) values than that of homogeneous catalysts for asymmetric epoxidation of 1-phenylcyclehexene and could be recycled three times.

Chiral Mn(III) salen complexes were synthesized and directly immobilized on pyrolytic waste tire char (PWTC) without modification of any organosilicon. The obtained heterogeneous catalysts showed high conversions and good enantioselectivities in asymmetric epoxidation of unfunctionalized olefins.Figure optionsDownload as PowerPoint slideHighlights
► The pyrolytic waste tire char (PWTC) was firstly used as a support in asymmetric epoxidation.
► Chiral Mn(III) salen complexes directly immobilized on PWTC without any organosilicon were reported firstly.
► The heterogeneous catalysts showed great catalytic performance.