Furan- and thiophene-functionalised bis-carbene ligands: Synthesis, silver(I) complexes, and catalysis
作者:David J. Nielsen、Kingsley J. Cavell、Mihai S. Viciu、Steven P. Nolan、Brian W. Skelton、Allan H. White
DOI:10.1016/j.jorganchem.2005.08.023
日期:2005.12
bis-imidazolium salts were tested as in situ additives in a Pd(0)-catalysed aryl amination coupling reaction, with the best observed activities around 20% of those seen with 1,3-bis(2,6-di-iso-propylphenyl)imidazolium chloride under identical conditions. The bulkier N-tBu and N-mesityl substituted salts were found to be more active than the N-methyl substituted analogues.
银(I)的新的呋喃和噻吩-官能化的亲核杂环卡宾(NHC)配合物通过新颖呋喃和噻吩-官能化的双-咪唑鎓盐的有Ag的反应制备2的两个样品O. Ñ甲基取代的呋喃阴离子复分解成四氟硼酸盐后,获得了适用于单晶X射线研究的α-和噻吩官能化的Ag(I)配合物。结构特征表明双核[Ag 2(Me CEC)2 ](BF 4)2(E = O,S)在两种情况下均具有离散的二十元双金属环的配方;然而,总的分子构象变化很大,特别是在两个桥接呋喃或噻吩杂环相对于银配位平面的方向上。功能化的双咪唑鎓盐在Pd(0)催化的芳基胺化偶联反应中作为原位添加剂进行了测试,观察到的最佳活性约为1,3-bis(2,6-di- iso)的20%-异丙基苯基)咪唑鎓氯化物在相同条件下进行。发现较大的N - t Bu和N-间苯甲基取代的盐比N-甲基取代的类似物更具活性。