Photoredox/Cobalt Dual Catalysis for Visible-Light-Mediated Alkene–Alkyne Coupling
作者:Pramod Rai、Kakoli Maji、Biplab Maji
DOI:10.1021/acs.orglett.9b01201
日期:2019.5.17
Dual photoredox transition-metal catalysis has recently emerged as a powerful tool for making synthetically challenging carbon–carbon bonds under milder reaction conditions. Herein, we report on the visible-light-mediated controlled generation of low-valent cobalt catalyst without the need for a metallic reductant. It enabled C–C bondformation via ene-yne coupling at roomtemperature. The generality
chelation‐assisted highly regio‐ and stereoselective directolefination of imidazoles with olefins has been developed. A broad range of C2‐substituted N‐(2‐pyrimidyl)imidazoles underwent smooth C5‐olefination with both activated and unactivated olefins to furnish the corresponding products in good to excellent yields with high tolerance of functional groups on both coupling partners in the presence of a
regioselective intermolecular 1,2‐aryl‐aminoalkylation of alkenes by photoredox/nickel dual catalysis is described here. This three‐component conjunctive cross‐coupling is highlighted by its first application of primary alkyl radicals, which were not compatible in previous reports. The readily prepared α‐silyl amines could be transferred to α‐amino radicals by photo‐induced single electron transfer step
Enantioselective Synthesis of Atropisomeric Anilides via Pd(II)-Catalyzed Asymmetric C–H Olefination
作者:Qi-Jun Yao、Pei-Pei Xie、Yong-Jie Wu、Ya-Lan Feng、Ming-Ya Teng、Xin Hong、Bing-Feng Shi
DOI:10.1021/jacs.0c09400
日期:2020.10.21
tremendous attention as a novel class of chiralcompounds possessing restricted rotation around an N-aryl chiral axis. However, in sharp contrast to the well-studied synthesis of biaryl atropisomers, the catalytic asymmetric synthesis of chiral anilides remains a daunting challenge, largely due to the higher degree of rotational freedom compared to their biaryl counterparts. Here we describe a highly