Institut für Organische Chemie, Albert-Ludwigs-Universität Freiburg, Albertstraße 21, 79104, Freiburg im Breisgau, Germany.
Angew Chem Int Ed Engl. 2022 May 9;61(20):e202200105. doi: 10.1002/anie.202200105. Epub 2022 Mar 16.
Intermolecular photocatalytic hydroaminoalkylation (HAA) of alkenes have emerged as a powerful method for the construction of alkyl amines. Although there are some studies aiming at stereoselective photocatalytic HAA reactions, the alkenes are limited to electrophilic alkenes. Herein, we report a highly regio-, diastereo-, and enantioselective HAA of electron-rich dienol ethers and α-amino radicals derived from α-amino acids using a unified photoredox and palladium catalytic system. This decarboxylative 1,2-Markovnikov addition enables the construction of vicinal amino tertiary ethers with high levels of regio- (up to >19 : 1 rr), diastereo- (up to >19 : 1 dr), and enantioselectivity control (up to >99 % ee). Mechanistic studies support a reversible hydropalladation as a key step.
分子间光催化氢氨烷基化(HAA)烯烃已成为构建烷基胺的有力方法。尽管有一些研究旨在实现立体选择性光催化 HAA 反应,但烯烃仅限于亲电烯烃。在此,我们报道了一种高度区域、立体和对映选择性的 HAA,使用统一的光氧化还原和钯催化体系,从α-氨基酸衍生的富电子二烯醇醚和α-氨基自由基。这种脱羧 1,2-Markovnikov 添加允许构建具有高区域选择性(高达>19:1 rr)、立体选择性(高达>19:1 dr)和对映选择性控制(高达>99%ee)的相邻氨基叔醚。机理研究支持可逆的氢钯化作为关键步骤。