Site-Directed Anchoring of an N-Heterocyclic Carbene on a Dimetal Platform: Evaluation of a Pair of Diruthenium(I) Catalysts for Carbene-Transfer Reactions from Ethyl Diazoacetate
作者:Biswajit Saha、Tapas Ghatak、Arup Sinha、S. M. Wahidur Rahaman、Jitendra K. Bera
DOI:10.1021/om200142p
日期:2011.4.11
utilities of the BArF (tetrakis(3,5-bis(trifluoromethyl)phenyl)borate) salts of these compounds are evaluated toward carbene-transfer reactions from ethyl diazoacetate including aldehyde olefination, cyclopropanation, and X−H (X = O, N) insertions. 1-BArF is clearly shown to be the superior catalyst. DFT calculations are undertaken to understand the influence of NHC binding on the electronic structures of the
在金属-金属单键合的二钌(I)平台上实现萘啶官能化的N-杂环卡宾(NHC)的定点锚固。用乙腈中的Ru 2(CH 3 COO)2(CO)4室温处理1-异丙基-3-(5,7-二甲基-1,8-萘-2-基)咪唑溴化铵(PIN·HBr)得到的不支持的化合物的Ru 2(CO)4(κ 2 ç 2,N 1 -pin)2溴2(1)。NHC配体的明智改变导致桥接化合物Ru 2(CO)4(CH 3 COO)(μ2 -κ 2 Ç 2,N 1 -bin)能Br(2)(BIN = 1-苄基-3-(3-苯基-1,8- naphthyrid -2-基)咪唑-2-亚基)。X射线分析显示,每个钌在赤道位点上的PIN螯合结合为1,而跨越二钌核心的BIN的桥螯合物结合为2。对这些化合物的BAr F(四(3,5-双(三氟甲基)苯基)硼酸酯)盐的催化效用进行了评估,以进行重氮乙酸乙酯的卡宾转移反应,包括醛烯化,环丙烷化和XH(X =