Low‐Temperature Nickel‐Catalyzed C−N Cross‐Coupling via Kinetic Resolution Enabled by a Bulky and Flexible Chiral
<i>N</i>
‐Heterocyclic Carbene Ligand
作者:Zi‐Chao Wang、Pei‐Pei Xie、Youjun Xu、Xin Hong、Shi‐Liang Shi
DOI:10.1002/anie.202103803
日期:2021.7.12
The transition-metal-catalyzed C−N cross-coupling has revolutionized the construction of amines. Despite the innovations of multiple generations of ligands to modulate the reactivity of the metal center, ligands for the low-temperature enantioselective amination of arylhalides remain a coveted target of catalyst engineering. Designs that promote one elementary reaction often create bottlenecks at
Spiro‐Bicyclic Bisborane Catalysts for Metal‐Free Chemoselective and Enantioselective Hydrogenation of Quinolines
作者:Xiang Li、Jun‐Jie Tian、Ning Liu、Xian‐Shuang Tu、Ning‐Ning Zeng、Xiao‐Chen Wang
DOI:10.1002/anie.201900907
日期:2019.3.26
A new series of spiro‐bicyclic bisborane catalysts has been prepared by means of hydroboration reactions of C2‐symmetric spiro‐bicyclic dienes with HB(C6F5)2 and HB(p‐C6F4H)2. When used for hydrogenation of quinolines, these catalysts give excellent yields and enantiomeric excesses, and show turnover numbers of up to 460. The most attractive feature of these metal‐free hydrogenation reactions was the
通过C 2对称螺双环二烯与HB(C 6 F 5)2和HB(p C 6 F 4 H)2的硼氢化反应制备了一系列新的螺双环双硼烷催化剂。当用于喹啉加氢时,这些催化剂具有出色的收率和对映体过量,并且显示出高达460的周转率。这些无金属加氢反应的最吸引人的特点是宽泛的官能团耐受性,使该方法可与现有方法互补喹啉加氢的方法。
Visible-Light Induction/Brønsted Acid Catalysis in Relay for the Enantioselective Synthesis of Tetrahydroquinolines
作者:Wenhui Xiong、Shan Li、Bo Fu、Jinping Wang、Qiu-An Wang、Wen Yang
DOI:10.1021/acs.orglett.9b01354
日期:2019.6.7
An efficient method merging Brønsted acid catalysis with visible-light induction for the highly enantioselectivesynthesis of tetrahydroquinolines has been developed. This mild process directly transforms 2-aminoenones into 2-substituted tetrahydroquinolines with excellent enantioselectivities through a relay visible-light-induced cyclization/chiral phosphoric acid-catalyzed transfer hydrogenation
Asymmetric Reduction of Quinolines: A Competition between Enantioselective Transfer Hydrogenation and Racemic Borane Catalysis
作者:Bochao Gao、Zaiqi Han、Wei Meng、Xiangqing Feng、Haifeng Du
DOI:10.1021/acs.joc.2c02905
日期:2023.3.3
A chiral phosphoric acid catalyzed asymmetrictransferhydrogenation of quinolines with regenerable dihydrophenanthridine derived by a borane-catalyzed hydrogenation of phenanthridine under H2 has been successfully realized. Despite the competition of a racemic hydrogenation pathway, a variety of tetrahydroquinolines were furnished in high yields with up to 91% ee.
已成功实现了由硼烷催化氢化菲啶在H 2 下衍生的手性磷酸催化喹啉与可再生二氢菲啶的不对称转移氢化反应。尽管存在外消旋氢化途径的竞争,但仍以高达 91% ee 的高产率提供了多种四氢喹啉。