Enantioselective Ni-Catalyzed Electrochemical Synthesis of Biaryl Atropisomers
作者:Hui Qiu、Bin Shuai、Yun-Zhao Wang、Dong Liu、Yue-Gang Chen、Pei-Sen Gao、Hong-Xing Ma、Song Chen、Tian-Sheng Mei
DOI:10.1021/jacs.9b13117
日期:2020.6.3
A scalable enantioselective nickel-catalyzed electrochemical reductive homocoupling of aryl bromides has been developed, affording enantioenriched axially chiral biaryls in good yield under mild conditions using electricity as a reductant in an undivided cell. Common metal reductants such as Mn or Zn powder resulted in significantly lower yields in the absence of electric current under otherwise identical
Synthesis of Axially Chiral 2,2′-Bisphosphobiarenes via a Nickel-Catalyzed Asymmetric Ullmann Coupling: General Access to Privileged Chiral Ligands without Optical Resolution
作者:Ziqing Zuo、Raphael S. Kim、Donald A. Watson
DOI:10.1021/jacs.0c12843
日期:2021.1.27
We report an asymmetric homocoupling of ortho-(iodo)arylphosphine oxides and ortho-(iodo)arylphosphonates resulting in highly enantioenriched axially chiral bisphosphine oxides and bisphosphonates. These products are readily converted to enantioenriched biaryl bisphosphines without need for chiralauxiliaries or optical resolution. This provides a practical route for the development of previously uninvestigated
Asymmetric Synthesis of Axially Chiral Naphthyl-C3-indoles via a Palladium-Catalyzed Cacchi Reaction
作者:Cong-Shuai Wang、Liang Wei、Cong Fu、Xin-Heng Wang、Chun-Jiang Wang
DOI:10.1021/acs.orglett.1c02574
日期:2021.10.1
ligands. Various efficient approaches have been disclosed for the construction of chiral six–six biaryl skeletons. In contrast, the enantioselective synthesis of axially chiral arylindoles through the strategy of de novo construction, other than the asymmetric functionalization of indoles, remain a challenging task. Herein we report an efficient Pd(0)/(S)-Segphos-catalyzed atroposelective Cacchi reaction
Palladium-Catalyzed [3 + 2] Annulation of Aryl Halides with 7-Oxa- and 7-Azabenzonorbornadienes via C(sp<sup>2</sup> or sp<sup>3</sup>)–H Activation
作者:Xiaojiao Li、Xianting Pan、Zisong Qi、Xingwei Li
DOI:10.1021/acs.orglett.2c03422
日期:2022.12.16
epoxy-5H-benzo[b]fluorenes, and their aza analogues have been accessed via palladium-catalyzed exo-selective [3 + 2] annulation between aryl halides and 7-oxa- and 7-azabenzonorbornadienes. The reaction is initiated by the oxidative addition of a carbon–halogen bond, with intramolecular C(sp2 or sp3)–H activation being a key step. The enantioselective version of the reaction was also briefly explored.
通过钯催化的芳基卤化物和 7-oxa- 和 7 之间的外选择性 [3 + 2] 环化,获得了一系列环氧苯并 [ k ] 荧蒽、环氧 -5 H -苯并 [ b ] 芴及其氮杂类似物-氮杂苯并降冰片二烯。该反应由碳-卤键的氧化加成引发,分子内 C(sp 2或 sp 3 )-H 活化是关键步骤。还简要探讨了该反应的对映选择性版本。
Bringmann, Gerhard; Hartung, Thomas; Goebel, Lothar, Liebigs Annalen der Chemie, 1992, # 3, p. 225 - 232
作者:Bringmann, Gerhard、Hartung, Thomas、Goebel, Lothar、Schupp, Olaf、Ewers, Christian L. J.、et al.