Nitrene Insertion into Aromatic and Benzylic C−H Bonds Catalyzed by Copper Complexes of Fluorinated Bis‐ and Tris(pyrazolyl)borates
作者:Tharun T. Ponduru、Zhicheng Sun、Thomas R. Cundari、H. V. Rasika Dias
DOI:10.1002/cctc.201901087
日期:2019.10.7
trace amounts of benzylic C−H insertion. The use of [H2B(3,5‐(CF3)2‐4‐(NO2)Pz)2]Cu(NCMe) that has an even weakly donating pyrazolate generated the arene C−H insertion product exclusively. The tris(pyrazolyl)borate complex [HB(3,5‐(CF3)2Pz)3]Cu(NCMe), in contrast, generated the benzylic amination product from mesitylene and PhI=NNs in 82 % yield with only very minor amounts of arene C−H functionalization
氟化的双和三(吡唑基)硼铜络合物可催化氮芳烃插入芳烃的CH键上,从而在室温下以良好或优异的收率有效地产生胺化产物。亚氨基碘,PhI = NTs(Ts =对甲苯磺酰基)和PhI = NNs(Ns =对硝基苯磺酰基)用作氮源。PhI = NNs的双(吡唑基)硼酸酯催化剂[H 2 B(3,5-(CF 3)2 Pz)2 ] Cu(NCMe)以87%的收率生产了均三甲苯的芳烃CH官能化产物苄基CH插入量。利用[H的2 B(3,5-(CF 3)2 -4-(NO 2)PZ)2具有甚至弱贡献的吡唑酸盐的] Cu(NCMe)专门生成芳烃CH插入产物。相比之下,三(吡唑基)硼酸酯络合物[HB(3,5-(CF 3)2 Pz)3 ] Cu(NCMe)从均三甲苯和PhI = NNs生成苄基胺化产物,产率仅为82%,芳烃CH功能化的数量。DFT计算表明,由[HB(3,5-(CF 3)2 Pz)3 ] Cu(NCMe)和PhI