Dual Effects of Cyclopentadienyl Ligands on Rh(III)-Catalyzed Dehydrogenative Arylation of Electron-Rich Alkenes

作者：Weidong Lin, Weiwei Li, Dandan Lu, Feng Su, Ting‐Bin Wen, Hui‐Jun Zhang · 发表于：ACS Catalysis · 年份：2018 · DOI：10.1021/acscatal.8b01753 · 被引用次数：67 · 研究领域：Catalytic C–H Functionalization Methods、Catalytic Cross-Coupling Reactions、Sulfur-Based Synthesis Techniques

Despite extensive research on transition metal-catalyzed Fujiwara–Moritani type C–H olefinations, the alkenes used in these transformations are still mainly limited to active acrylate esters and styrenes. Selective aryl C–H olefination with electron-rich alkenes is recognized as a challenging issue. We herein report that simple and readily accessible electron-deficient [CpRh(III)] and [Cp CF 3 Rh(III)] (Cp CF 3 = C 5 Me 4 CF 3 ) complexes are powerful catalysts for dehydrogenative arylation of electron-rich alkenes, including vinyl acetates, enamides, and vinyl ethers. Employing an electron-withdrawing Cp or Cp CF 3 ligand instead of the privileged Cp* (C 5 Me 5 ) ligand not only can facilitate the electrophilic aryl C–H rhodation but also can lower the olefin insertion barrier. Both electron-withdrawing and electron-donating directing groups such as -CONR 2 and -NHAc could be employed in these reactions, which provides convenient routes toward a series styryl acetates, N -acetylindoles, and aryl methyl ketones.