Heterogeneous asymmetric epoxidation of unfunctionalized olefins catalyzed by polymer-bound (salen)manganese complexes
摘要:
The synthesis of three different polymer-bound chiral Mn-salen complexes (Poly-1, -2a, -2b) is reported, along with their application as recyclable catalysts in heterogeneous asymmetric epoxidation with mCPBA/NMO of several unfunctionalized olefins. The introduction of a spacing group between the polymeric chain and the metal centre (Poly-2a and -2b) considerably increased the enantioselectivity of the process. Copyright (C) 1996 Elsevier Science Ltd
Heterogeneous chiral Mn(III) salen catalysts for the epoxidation of unfunctionalized olefins immobilized on mesoporous materials with different pore sizes
作者:Kai Yu、Zhicheng Gu、Runan Ji、Lan-Lan Lou、Shuangxi Liu
DOI:10.1016/j.tet.2008.10.051
日期:2009.1
Two chiral Mn(III) salen complexes were immobilized onto a series of mesoporous MCM-41 and MCM-48 materials with different pore sizes and the as-synthesized catalysts were active and enantioselective for the asymmetricepoxidation of styrene and indene. The results of XRD, FTIR, DR UV–vis, and N2 sorption showed that the chiral Mn(III) salen complexes were anchored in the channels of mesoporous materials
Chiral manganese(III) salen catalysts immobilized on MCM-41 and delaminated zeolites ITQ-2 and ITQ-6 through new axial coordinating linkers
作者:I DOMINGUEZ、V FORNES、M SABATER
DOI:10.1016/j.jcat.2004.08.021
日期:2004.11.15
report that the catalytic behavior and enantioselectivity of three different chiral Mn(III) salen complexes anchored to traditional supports such as MCM-41 (38-Å pore diameter) and delaminated zeolitic materials ITQ-2 and ITQ-6 strongly depend on whether the complexes are attached to the surfaces through the chiral equatorial tetradentate salen ligand or via the apicalligand. As for the case of unsupported
The synthesis of three different polymer-bound chiral Mn-salen complexes (Poly-1, -2a, -2b) is reported, along with their application as recyclable catalysts in heterogeneous asymmetric epoxidation with mCPBA/NMO of several unfunctionalized olefins. The introduction of a spacing group between the polymeric chain and the metal centre (Poly-2a and -2b) considerably increased the enantioselectivity of the process. Copyright (C) 1996 Elsevier Science Ltd