Rhodium(I)‐Catalyzed Asymmetric Hydroarylative Cyclization of 1,6‐Diynes to Access Atropisomerically Labile Chiral Dienes

作者：Panjie Hu, Lingfei Hu, Xiao‐Xi Li, Xiao‐Xi Li, Mengxiao Pan, Gang Lü, Xingwei Li, Xingwei Li · 发表于：Angewandte Chemie International Edition · 年份：2023 · DOI：10.1002/anie.202312923 · 被引用次数：28 · 研究领域：Axial and Atropisomeric Chirality Synthesis、Chemical synthesis and alkaloids、Molecular spectroscopy and chirality

Abstract Axially chiral open‐chained olefins are an underexplored class of atropisomers, whose enantioselective synthesis represents a daunting challenge due to their relatively low racemization barrier. We herein report rhodium(I)‐catalyzed hydroarylative cyclization of 1,6‐diynes with three distinct classes of arenes, enabling highly enantioselective synthesis of a broad range of axially chiral 1,3‐dienes that are conformationally labile (Δ G ≠ ( rac )=26.6–28.0 kcal/mol). The coupling reactions in each category proceeded with excellent enantioselectivity, regioselectivity, and Z/E selectivity under mild reaction conditions. Computational studies of the coupling of quinoline N ‐oxide system reveal that the reaction proceeds via initial oxidative cyclization of the 1,6‐diyne to give a rhodacyclic intermediate, followed by σ‐bond metathesis between the arene C−H bond and the Rh−C(vinyl) bond, with subsequent C−C reductive elimination being enantio‐determining and turnover‐limiting. The DFT‐established mechanism is consistent with the experimental studies. The coupled products of quinoline N ‐oxides undergo facile visible light‐induced intramolecular oxygen‐atom transfer, affording chiral epoxides with complete axial‐to‐central chirality transfer.