Polynuclear Architectures with Di- and Tricarbene Ligands

The 1,3,5-triimidazolium-substituted benzene cation in H3-1(PF6)3 reacts with Hg(OAc)2 to yield the cylinder-like trinuclear hexacarbene complex [Hg3(1)2](PF6)6. Reaction of imidazole with 1,4-dibromobenzene gives 1,4-bis(1-imidazolyl)benzene (2), which after dialkylation with ethyl bromide and salt metathesis yields the new diimidazolium salt H2-3(PF6)2. Two equivalents of H2-3(PF6)2 react with 2 equiv of Ag2O to give the dinuclear AgI tetracarbene complex [Ag2(3)2](PF6)2, which after transmetalation with [AuCl(SMe2)] yields the AuI tetracarbene complex [Au2(3)2](PF6)2. In contrast to the formation of the tetracarbene complexes of type [M2(3)2]2+ (M = AgI, AuI), the diimidazolium salt H2-3(PF6)2 reacts with Hg(OAc)2 to yield the dinuclear HgII dicarbene complex [Hg2(OAc)2(3)](PF6)2, where each mercury center is coordinated by one carbene carbon atom and one acetate oxygen atom. The crystal structure of [Hg2(OAc)2(3)](PF6)2 reveals that the complex forms a coordination polymer via intra- and intermolecular acetate bridges between HgII centers.

H3-1(PF6)3中的1,3,5-三咪唑鎓取代苯阳离子（PF6为六氟磷酸根（PF6））与乙酸汞(Hg(OAc)2)反应，生成圆柱状三核六卡宾配合物[Hg3(1)2](PF6)6。咪唑与1,4-二溴苯反应得到1,4-二(1-咪唑基)苯(2)，该产物经溴乙烷双烷基化以及盐复分解反应后，生成新型二咪唑鎓盐H2-3(PF6)2。两当量的H2-3(PF6)2与两当量的氧化银(Ag2O)反应，得到双核一价银(AgI)四卡宾配合物[Ag2(3)2](PF6)2；该配合物经与[AuCl(SMe2)]的转金属化反应后，生成一价金(AuI)四卡宾配合物[Au2(3)2](PF6)2。与[M2(3)2]²⁺型（M=AgI、AuI）四卡宾配合物的生成过程不同，二咪唑鎓盐H2-3(PF6)2与乙酸汞(Hg(OAc)2)反应，得到双核二价汞(HgII)二卡宾配合物[Hg2(OAc)2(3)](PF6)2，该配合物中每个汞中心均与一个卡宾碳原子以及一个乙酸根氧原子配位。[Hg2(OAc)2(3)](PF6)2的晶体结构显示，该配合物通过HgII中心之间的分子内及分子间乙酸根桥联作用，形成了配位聚合物。