Catalytic, Enantioselective Addition of Alkyl Radicals to Alkenes via Visible-Light-Activated Photoredox Catalysis with a Chiral Rhodium Complex
作者:Haohua Huo、Klaus Harms、Eric Meggers
DOI:10.1021/jacs.6b03399
日期:2016.6.8
An efficient enantioselective addition of alkyl radicals, oxidatively generated from organotrifluoroborates, to acceptor-substituted alkenes is catalyzed by a bis-cyclometalated rhodium catalyst (4 mol %) under photoredox conditions. The practical method provides yields up to 97% with excellent enantioselectivities up to 99% ee and can be classified as a redox neutral, electron-transfer-catalyzed reaction
Nitroxide‐Catalyzed Oxidative Amidation of Aldehydes to Yield
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‐Acyl Azoles Using Sodium Persulfate
作者:Fabrizio Politano、Arturo León Sandoval、Mason L. Witko、Katrina E. Doherty、Chelsea M. Schroeder、Nicholas E. Leadbeater
DOI:10.1002/ejoc.202101239
日期:2022.1.27
In the presence of a catalytic quantity of a nitroxide salt, sodium persulfate can be used for the oxidative amidation of aldehydes to yield acyl azoles.
Magnesium Complexes as Highly Effective Catalysts for Conjugate Cyanation of α,β-Unsaturated Amides and Ketones
作者:Jinlong Zhang、Xihong Liu、Rui Wang
DOI:10.1002/chem.201304835
日期:2014.4.22
Asymmetric cyanation of trimethylsilyl cyanide (TMSCN) with α,β‐unsaturated amides and ketones, respectively, catalyzed by bifunctional mononuclear 1,1′‐bi‐2‐naphthol (BINOL)–Mg and binuclear bis(prophenol)–Mg catalysts was realized. A series of synthetically important 1,4‐cyano products were obtained with good to high enantioselectivities (up to 97 % ee).
A highly enantioselective tandem Michael/ring‐closurereaction of α,β‐unsaturated pyrazoleamides and amidomalonates has been accomplished in the presence of a chiral N,N′‐dioxide–Yb(OTf)3 complex (Tf: trifluoromethanesulfonyl) to give various substituted chiral glutarimides with high yields and diastereo‐ and enantioselectivities. Moreover, this methodology could be used for gram‐scale manipulation
Fluorinated Sulfinates as Source of Alkyl Radicals in the Photo‐Enantiocontrolled β‐Functionalization of Enals
作者:Ricardo I. Rodríguez、Marina Sicignano、José Alemán
DOI:10.1002/anie.202112632
日期:2022.2.21
use of gem-difluoro sulfinates in visible-light photocatalysis for the construction of new C−C bonds in a chiral fashion is presented. This was tackled by rerouting the chemical pathway of alkyl sulfonyl radicals from traditional sulfonylation to alkylation performance. The efficacy of these sulfinates for assisting SO2 extrusion is shown by allowing the installation of CF2-bearing scaffolds, a modern
介绍了宝石-二氟亚磺酸盐在可见光光催化中前所未有的用途,用于以手性方式构建新的 C-C 键。这是通过将烷基磺酰基自由基的化学途径从传统的磺酰化重新路由到烷基化性能来解决的。这些亚磺酸盐有助于 SO 2挤出的功效通过允许安装带有 CF 2的支架来显示,这是制药领域的一项现代任务。