[3]Dendralene Synthesis: Rhodium(III)-Catalyzed Alkenyl CH Activation and Coupling Reaction with Allenyl Carbinol Carbonate
作者:Honggen Wang、Bernhard Beiring、Da-Gang Yu、Karl D. Collins、Frank Glorius
DOI:10.1002/anie.201306754
日期:2013.11.18
[3]DendrAl(l)ene! A new synthesis of [3]dendralenes is based on a RhIII‐catalyzed alkenyl CH activation and coupling reaction with allenyl carbinol carbonates (see scheme; DG=directing group). A variety of [3]dendralenes with diverse substitution patterns are accessible with good efficiency. The reaction is highly stereoselective and compatible with different directing groups and numerous functional
Cobalt‐Catalyzed C8‐Dienylation of Quinoline‐
<i>N</i>
‐Oxides
作者:Rahul K. Shukla、Akshay M. Nair、Salman Khan、Chandra M. R. Volla
DOI:10.1002/anie.202003216
日期:2020.9.21
An efficient Cp*CoIII‐catalyzed C8‐dienylation of quinoline‐N‐oxides was achieved by employing allenes bearing leaving groups at the α‐position as the dienylating agents. The reaction proceeds by CoIII‐catalyzed C−H activation of quinoline‐N‐oxides and regioselective migratory insertion of the allene followed by a β‐oxy elimination, leading to overall dienylation. Site‐selective C−H activation was
喹啉N-氧化物的有效Cp * Co III催化C8-二烯基化反应是通过使用在α-位带有离去基团的烯作为二烯化剂来实现的。该反应通过Co III催化喹啉N氧化物的CH H活化和丙二烯的区域选择性迁移插入,然后被β氧基消除而进行,从而导致整体二烯化。在温和的反应条件下,以优异的选择性实现了位点选择性的CH活化,并且发现30 mol%的NaF添加剂对于有效的二烯基化至关重要。该方法具有高立体选择性,温和的反应条件和良好的官能团耐受性。喹啉N的C8烯基化在没有离开基团作为偶联配偶体的丙二烯的情况下实现了氧化。此外,进行了克级制备和初步的机理实验,以深入了解反应机理。