摘要 已经开发了一系列有效的催化系统来控制 α-酮酯与硝基烯烃共轭加成的双重对映选择性。使用手性二胺 (1 S ,1' S )-1,1'-双异二氢吲哚作为手性配体,以 (Cu(OAc) 2 ·H 2 O 或 Ni(OAc) 2 ·4H 2 O 为催化剂)以高水平的对映选择性(94% ee vs 93% ee)轻松获得由共轭加成反应产生的各个对映异构体。此外,使用 Cu(OAc) 2 ·H 2 O 作为金属中心允许对映选择性通过调节手性二胺配体的刚性(94% ee vs 94% ee)来切换共轭加成反应。
An asymmetric hydrogenation of sterically hindered β,β-disubstituted enones has been well-established by using a ruthenium complex composed of an achiral diphosphane and a chiral diamine as catalyst, wherein the carbonyl group was selectively hydrogenated to give a wide range of chiral allylic alcohols with high levels of enantioselectivity and complete chemoselectivity.
A Ruthenium Catalyst with Simple Triphenylphosphane for the Enantioselective Hydrogenation of Aromatic Ketones
作者:Han Zhou、Hanmin Huang
DOI:10.1002/cctc.201300080
日期:2013.8
An efficient Ru catalyst constructed from simple and commercially available triphenylphosphane and enantiopure (1S,1′S)‐1,1′‐biisoindoline (BIDN) was applied to the asymmetric hydrogenation of aromatic ketones. A range of simple aromatic ketones could be hydrogenated with good to excellent enantioselectivities (up to 95 % ee). An appropriate enantioselective transition state was proposed to explain
Enantioselective Epoxidation of Electron-Deficient Alkenes Catalyzed by Manganese Complexes with Chiral N<sub>4</sub>
Ligands Derived from Rigid Chiral Diamines
作者:Xiangning Chen、Bao Gao、Yijin Su、Hanmin Huang
DOI:10.1002/adsc.201700541
日期:2017.8.7
series of tetradentate sp2N/sp3N hybrid chiral N4 ligands derived from rigid chiral diamines were synthesized, which enabled the first manganese-catalyzed enantioselective epoxidation of electron-deficientalkenes with hydrogenperoxide (H2O2) as an oxidant. The reaction furnishes enantiomerically pure epoxy amides, epoxy ketones as well as epoxy esters in good yields and excellent enantioselectivities
合成了一系列衍生自刚性手性二胺的四齿sp 2 N / sp 3 N杂合手性N 4配体,这使锰能够以过氧化氢(H 2 O 2)为氧化剂,首次对缺电子烯烃进行对映选择性环氧化。。该反应以较低的催化剂负载量提供了对映体纯的环氧酰胺,环氧酮以及环氧酯,具有良好的收率和优异的对映选择性(最高99.9%ee)。对结构-活性关系的初步研究表明,保持sp 3的相对较低的供电子能力N和N 2配体的sp 2 N的相对较高的供电子能力有利于获得更高的活性和选择性,从而为我们理解H 2 O 2的环氧化提供了新的视角。