reactions has been examined. There is no significant difference in catalytic activities between 2 and 4 in Suzuki–Miyaura coupling reactions. However, the catalytic activity of 2 in the Kumada–Corriu coupling of ArBr with cyclohexylmagnesium bromide is quite different from that of 4. Thus complex 2 is active for the cross coupling, but complex 4 is active for the reduction of aryl halides.
合成并表征了含2,7-双(间苯二甲酰
咪唑啉基)
萘啶(NHC - NP)的
钯配合物。[Ag 3(NHC - NP)2 }(PF 6)3 ]与[Pd(PhCN)2 Cl 2 ]的反应提供了一种由两个NHC - NP单元桥接的不寻常的二
钯络合物,形成了一个20元的双核
金属环[ Pd 2(NHC - NP)2 Cl 2 }(PF 6)](2)高产。用KI治疗2
丙酮产生中性物质[Pd 2(NHC - NP)I 4 ](3)。同时,
吡啶基N-杂环卡宾(NHC - Py)前体1-(2-
吡啶基)-3-间苯二甲酰
咪唑氯化物,与Pd 2(dba)3直接反应形成单核
钯配合物[Pd(NHC - Py)Cl 2 ](4)。通过元素分析和NMR光谱对这些配合物进行表征,并通过X射线衍射分析进一步鉴定3和4的结构。这些
钯配合物在Suzuki–Miyaura和Kumada–Corriu偶联反应中的使用已得到检验。在S