Ruthenium-catalyzed cascade C–H activation/annulation of <i>N</i>-alkoxybenzamides: reaction development and mechanistic insight
作者:Liangliang Song、Xiaoyong Zhang、Xiao Tang、Luc Van Meervelt、Johan Van der Eycken、Jeremy N. Harvey、Erik V. Van der Eycken
DOI:10.1039/d0sc04434b
日期:——
to alkyne insertion. This is highly different compared to the conventional mechanism of transition metal-catalyzed C–Hactivation/annulation with alkynes, involving alkyne insertion prior to N–O bond cleavage. Via this pathway, the in situ generated acetic acid from the N–H/C–Hactivation step facilitates the N–O bond cleavage to give the Ru-nitrene species. Besides the conventional mechanism forming
Dehydrative C–H/N–OH Functionalizations in H<sub>2</sub>O by Ruthenium(II) Catalysis: Subtle Effect of Carboxylate Ligands and Mechanistic Insight
作者:Fanzhi Yang、Lutz Ackermann
DOI:10.1021/jo501884v
日期:2014.12.19
A ruthenium(II) complex derived from the electron-deficient aromatic carboxylic acid 3-(F3C)C6H4CO2H proved to be a highly efficient catalyst for dehydrative alkyne annulation by NH-free hydroxamic acids in water. The C–H/N–OH functionalization occurred with excellent positional selectivity as well as ample substrate scope, setting the stage for effective intermolecular alkenylations of hydroxamic
衍生自缺电子芳族羧酸3-(F 3 C)C 6 H 4 CO 2 H的钌(II)络合物被证明是通过水中不含NH的异羟肟酸使炔烃脱水的高效催化剂。C–H / N–OH官能化具有出色的位置选择性以及充足的底物范围,为异羟肟酸的有效分子间烯基化奠定了基础。详细的力学研究表明,通过羧酸盐的协助以及随后的迁移性炔烃插入,还原消除和分子内氧化加成,可在动力学上实现C–H的金属化。