The synthesis and utility of the novel axially chiral bis-urea ligand BINUREA are described. A complex of this urea ligand with ytterbium triflate and DBU can be used in the catalytic enantioselectiveDiels–Alder reaction of Danishefsky-type diene and electron-deficient olefins to give the adducts in good to excellent yield and enantiomeric excess (ee).
Remote Radical Trifluoromethylation: A Unified Approach to the Selective Synthesis of γ-Trifluoromethyl α,β-Unsaturated Carbonyl Compounds
作者:Marina Briand、Linh D. Thai、Flavien Bourdreux、Nicolas Vanthuyne、Xavier Moreau、Emmanuel Magnier、Elsa Anselmi、Guillaume Dagousset
DOI:10.1021/acs.orglett.2c03676
日期:2022.12.30
Site-selective trifluoromethylation of silyl dienol ethers derived from α,β-unsaturated aldehydes, ketones, and amides was achieved for the first time in the remote γ position. This photoredox catalyzed process is quite general to compounds bearing many functionalities and is applicable to the late-stage functionalization of biorelevant molecules. The use of S-perfluoroalkyl sulfoximines as ·RF radical
首次在远程 γ 位置实现了衍生自 α,β-不饱和醛、酮和酰胺的甲硅烷基二烯醇醚的位点选择性三氟甲基化。这种光氧化还原催化过程对于具有许多功能的化合物非常普遍,适用于生物相关分子的后期功能化。使用S-全氟烷基亚砜亚胺作为·R F自由基源可以将反应推广到其他全氟烷基(R F = CF 2 H,C 4 F 9)。重要的是,公开了一种前所未有的对映选择性 C(sp 3 )–H 全氟烷基化过程。