Highly Regio- and Enantioselective Reductive Coupling of Alkynes and Aldehydes via Photoredox Cobalt Dual Catalysis
作者:Yan-Lin Li、Shi-Qi Zhang、Jie Chen、Ji-Bao Xia
DOI:10.1021/jacs.1c03527
日期:2021.5.19
A Co-catalyzed highly regio- and enantioselective reductive coupling of alkynes and aldehydes has been developed under visible light photoredox dual catalysis. A variety of enantioenriched allylic alcohols have been obtained by using unsymmetrical internal alkynes and commercially available catalyst, chiral ligand, and reagents. It is noteworthy that this approach has considerable advantages, such
在可见光光氧化还原双催化下开发了一种共催化的炔烃和醛的高度区域选择性和对映选择性还原偶联。通过使用不对称内部炔烃和市售催化剂、手性配体和试剂,已经获得了多种对映体富集的烯丙醇。值得注意的是,这种方法具有相当大的优势,例如出色的区域-(> 40 个示例> 95:5)、立体-(高达> 95:5 E / Z)和对映选择性(92-99% ee,> 35个例子)控制,反应条件温和,底物范围广,官能团相容性好,使其对映选择性炔-醛还原偶联反应有了很大的改进。
Borane-Catalyzed Direct Asymmetric Vinylogous Mannich Reactions of Acyclic α,β-Unsaturated Ketones
作者:Jun-Jie Tian、Ning Liu、Qi-Fei Liu、Wei Sun、Xiao-Chen Wang
DOI:10.1021/jacs.1c00006
日期:2021.3.3
Herein, we report that, by using chiral bicyclic bisborane catalysts, we have achieved the first highly regio-, diastereo-, and enantioselective direct asymmetric vinylogous Mannich reactions of acyclic α,β-unsaturatedketones. The strong Lewis acidity and steric bulk of the bisborane catalysts were essential for the observed high yields and selectivities.
<scp>Nickel‐Catalyzed</scp>Reductive Coupling of Aldehydes with Alkynes Mediated by Alcohol<sup>†</sup>
作者:Yan‐Long Zheng、Mengchun Ye
DOI:10.1002/cjoc.201900543
日期:2020.5
A nickel‐catalyzed reductive coupling of aldehydes with alkynes using 1‐phenylethanol as reducing agent has been developed. The key achievement of this work is that we demonstrate environmentally benign 1‐phenylethanol can serve as a viable alternative reducing agent to Et3B, ZnEt2 and R3SiH for the nickel‐catalyzed reductive coupling reaction of aldehyde and alkynes.
Cp*Ru(PN) Complex-Catalyzed Isomerization of Allylic Alcohols and Its Application to the Asymmetric Synthesis of Muscone
作者:Masato Ito、Sachiko Kitahara、Takao Ikariya
DOI:10.1021/ja050770g
日期:2005.5.1
Highly efficient isomerization of allylicalcohols into saturated carbonyls is accomplished using the catalyst system of Cp*RuCl[Ph2P(CH2)2NH2-kappa2-P,N]-KOt-Bu (Cp* = eta5-C5(CH3)5) under mild conditions. Mechanistic consideration based on isotope-labeling experiments indicated the present reaction is applicable to the asymmetricisomerization of racemic sec-allylic alcohols with a prochiral olefin