N-Heterocyclic Carbene Boranes are Hydrogen Donors in Masamune–Bergman Reactions of Benzo[3,4]cyclodec-3-ene-1,5-diynes
作者:Takashi Watanabe、Steven J. Geib、Dennis P. Curran、Tsuyoshi Taniguchi
DOI:10.1021/acs.joc.7b01981
日期:2017.12.15
5-diyne with N-heterocyclic carbene boranes (NHC-boranes) provided mixtures of 9-borylated 1,2,3,4-tetrahydroanthracenes along with 1,2,3,4-tetrahydroanthracene. These products indicate that NHC-boranes serve as hydrogen donors to a p-benzyne intermediate formed by the Masamune–Bergman reaction. Experimental results support a radical mechanism in nonpolar solvents, but suggest that ionic mechanisms compete
苯并[3,4]环癸-3-烯-1,5-二炔与N-杂环卡宾硼烷(NHC-硼烷)的热反应可提供9-硼化的1,2,3,4-四氢蒽与1的混合物2,3,4-四氢蒽。这些产物表明,NHC-硼烷是由Masamune-Bergman反应形成的对-苄基中间体的氢供体。实验结果支持在非极性溶剂中的自由基机理,但是表明当在极性溶剂中进行反应时,离子机理参与1,2,3,4-四氢蒽的生产。