Rhodium-catalyzed atroposelective access to trisubstituted olefins via C-H bond olefination of diverse arenes.
Xiaohan ZhuRuijie MiJie YinFen WangXingwei LiPublished in: Chemical science (2023)
The atroposelective synthesis of axially chiral acyclic olefins remains a daunting challenge due to their relatively lower racemization barriers, especially for trisubstituted ones. In this work, atroposelective C-H olefination has been realized for synthesis of open-chain trisubstituted olefins via C-H activation of two classes of (hetero)arenes in the coupling with sterically hindered alkynes. The employment of phenyl N -methoxycarbamates as arene reagents afforded phenol-tethered olefins, with the carbamate being a traceless directing group. The olefination of N -methoxy-2-indolylcarboxamides afforded the corresponding chiral olefin by circumventing the redox-neutral [4 + 2] annulation. The reactions proceeded with excellent Z / E selectivity, chemoselectivity, regioselectivity, and enantioselectivity in both hydroarylation systems.