Mechanism of the Mild Functionalization of Arenes by Diboron Reagents Catalyzed by Iridium Complexes. Intermediacy and Chemistry of Bipyridine-Ligated Iridium Trisboryl Complexes
作者:Timothy M. Boller、Jaclyn M. Murphy、Marko Hapke、Tatsuo Ishiyama、Norio Miyaura、John F. Hartwig
DOI:10.1021/ja053433g
日期:2005.10.1
electron-poor arenes than with electron-rich arenes. However, both the stoichiometric and catalytic reactions also occur faster with the electron-rich heteroarenes thiophene and furan than with arenes, perhaps because eta(2)-heteroarene complexes are more stable than the eta(2)-arene complexes and the eta(2)-heteroarene or arene complexes are intermediates that precede oxidative addition. Kinetic studies on the
本文描述了芳烃与二硼试剂 B(2)pin(2)(双频哪醇二硼烷(4))在 4,4'-二叔丁基联吡啶 (dtbpy) 和烯烃连接的卤化铱或烯烃连接的铱醇盐配合物。这项工作将催化剂静止状态确定为 [Ir(dtbpy)(COE)(Bpin)(3)](COE = 环辛烯,Bpin = 4,4,5,5-四甲基-1,3,2-二氧杂环戊二烯基)。[Ir(dtbpy)(COE)(Bpin)(3)] 由 [Ir(COD)(OMe)](2)、dtbpy、COE 和 HBpin 通过独立合成以高产率制备。这种复合物是由 [Ir(COD)(OMe)](2)、dtbpy、COE 和 B(2)pin(2) 以低产率形成的。动力学研究表明,该复合物在 COE 可逆解离后与芳烃反应。在 COE 解离和 B(2)pin(2) 的还原消除后,芳烃与 Ir(I) 复合物 [Ir(dtbpy)Bpin] 反应的另一种机制不会发生