RETRACTED: Enantioselective epoxidation of unfunctionalized olefins by Jacobsen's catalyst immobilized on amino-modified ZnPS-PVPA
作者:Jing Huang、Yan Iuo、Jiali Cai
DOI:10.1016/s1872-2067(16)62489-0
日期:2016.9
Catalytic asymmetric epoxidation of alkenes is a powerful method for the synthesis of chiral organic compounds. A recyclable chiral Jacobsen's catalyst immobilized on ZnPS-PVPA on diamines gave high catalytic activity(conversion > 99%, ee > 99%) in the asymmetric epoxidations of unfunctionalized olefins. The synergistic effect of the support ZnPS-PVPA and the linkage as well as chiral salen Mn center
Asymmetric epoxidation of unfunctionalized olefins catalyzed by chiral salen‐Mn (III) immobilized on alkoxyl‐modified ZnPS‐PVPA
作者:Jing Huang、Junjie Xie、Jiali Cai
DOI:10.1002/aoc.4982
日期:2019.8
Novel layered heterogeneous chiral salenMn (III) catalysts anchored onto ZnPS‐PVPA by means of click chemistry are synthesized and employed in asymmetricepoxidations of unfunctionalized olefins. The catalysts manifest superior catalytic performances (conv%, up to >99; ee%, up to >99) according to the epoxidations of α‐methylstyrene, styrene, indene and 1‐octene. But for 6‐cyano‐ 2,2‐dimethylchromene
合成了通过点击化学方法锚定在ZnPS-PVPA上的新型层状非均相手性Salen Mn(III)催化剂,并将其用于未官能化烯烃的不对称环氧化。根据α-甲基苯乙烯,苯乙烯,茚和1-辛烯的环氧化,该催化剂表现出优异的催化性能(转化率,最高> 99; ee%,最高> 99)。但是对于6-氰基-2-2,2-二甲基苯甲基和6-硝基-2-2,2-二甲基苯甲基,环氧化物的构型是相反的。此外,催化剂经过九次循环使用后仍可显示出可比的性能(收率82%; ee 86%),并且在大规模反应中具有出色的功能,为工业应用铺平了道路。
Dicationic chiral Mn(III) salen complex exchanged in the interlayers of montmorillonite clay: a heterogeneous enantioselective catalyst for epoxidation of nonfunctionalized alkenes
作者:R Kureshy
DOI:10.1016/j.jcat.2003.07.012
日期:2004.1.1
Enantioselective epoxidation of styrene, indene, and 2,2-dimethyl-6-nitro chromene mediated by 1–4 complexes (0.4–2 mol%) as catalysts in the presence of pyridine N-O as axial base with NaOCl as an oxidant gave quantitative epoxide yield (>99%) under biphasic homogeneous conditions. On employment of catalysts 1′–4′ under similar epoxidation condition, the epoxide selectivity in the case of styrene was
Ionic liquid-functionalized graphene oxide as an efficient support for the chiral salen Mn(<scp>iii</scp>) complex in asymmetric epoxidation of unfunctionalized olefins
oxide (GO) was prepared and used to support chiral salen Mn(III) complexes. Technologies of characterization suggested that the intact chiral complex was covalently appended on flat planes and edge of the GO sheet through an imidazolium-based IL linker. The flexible layer-structure, as well as the active role of the IL linker in overall reaction, makes the novel heterogeneous catalyst efficient and universal