Arrowsmith Merle, Böhnke Julian, Braunschweig Holger, Gao Haopeng, Légaré Marc-André, Paprocki Valerie, Seufert Jens
Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.
Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.
Chemistry. 2017 Sep 7;23(50):12210-12217. doi: 10.1002/chem.201700500. Epub 2017 Apr 10.
Sterically hindered, in situ generated 1,3,4-substituted 1,2,3-triazol-5-ylidene mesoionic carbenes (MICs) were employed to stabilize a number of aryl- and heteroaryldihaloboranes, as well as the first MIC-supported diborane. Reduction of borane adducts of the 1-(2,6-diisopropylphenyl)-3-methyl-4-tert-butyl-1,2,3-triazol-5-ylidene ligand with KC in non-coordinating solvents led to intramolecular C-H- and, C-C-activation at an isopropyl residue of the supporting ligand. DFT calculations showed that each of these activation reactions proceeds via a different isomer of a borylene intermediate.
使用空间位阻的原位生成的1,3,4-取代的1,2,3-三唑-5-亚基中氮茚卡宾（MICs）来稳定多种芳基和杂芳基二卤硼烷以及首个由MICs支撑的乙硼烷。在非配位溶剂中，用KC还原1-(2,6-二异丙基苯基)-3-甲基-4-叔丁基-1,2,3-三唑-5-亚基配体的硼烷加合物，导致支撑配体的异丙基残基发生分子内C-H和C-C活化。密度泛函理论计算表明，这些活化反应中的每一个都通过硼烯中间体的不同异构体进行。
