Syntheses, structures and electrochemical properties of single and double helical inorganic complexes containing new polypyridine ligands
作者:Paul Kwok-Keung Ho、Shie-Ming Peng、Kwok-Yin Wong、Chi-Ming Che
DOI:10.1039/dt9960001829
日期:——
New polypyridines [1,3-bis(2,2′:6′,2″-terpyridin-6-yl)benzene L1 and 1,3-bis[4-(4-tert-butylphenyl)-2,2′:6′,2″-terpyridin-6-yl)benzene] L2 were prepared. Their reactions with copper(II) acetate and silver(I) acetate gave [Cu2L12]4+, [Cu2L22]4+, [Ag2L12]2+ and [Ag2L22]2+ while [Ru2L2(terpy)2]4+ was obtained from [Ru(terpy)Cl3](terpy = 2,2′:6′,2″-terpyridine) with L2. The complexes [Cu2L22][PF6]4·6MeCN and [Ag2L22][PF6]·Me2CO have been established by X-ray crystal analyses to have double helical structures. Electrospray mass spectrometry showed that the double helical [Cu2L22]4+ and [Ag2L12]2+ complexes and the single helical [Ru2L2(terpy)2]4+ complex are the only species present in solutions. All five complexes undergo reversible oxidations or reductions. Interestingly, the electrochemical data indicate substantial electronic coupling within the bimetallic double helical [M2L2]3+(M = Cu or Ag, L = L1 and L2) but not the single helical [Ru2L2(terpy)2]4+ systems.
新的聚吡啶[1,3-双(2,2′:6′,2″-三联吡啶-6-基)苯L1和1,3-双[4-(4-叔丁基苯基)-2,2′:制备6',2''-三联吡啶-6-基)苯]L2。它们与乙酸铜(II)和乙酸银(I)反应得到[Cu2L12]4+、[Cu2L22]4+、[Ag2L12]2+和[Ag2L22]2+,同时得到[Ru2L2(terpy)2]4+由 [Ru(terpy)Cl3](terpy = 2,2′:6′,2″-三联吡啶) 与 L2 合成。通过X射线晶体分析确定配合物[Cu2L22][PF6]4·6MeCN和[Ag2L22][PF6]·Me2CO具有双螺旋结构。电喷雾质谱分析表明,双螺旋[Cu2L22]4+ 和[Ag2L12]2+ 配合物以及单螺旋[Ru2L2(terpy)2]4+ 配合物是溶液中存在的唯一物质。所有五种配合物都会发生可逆的氧化或还原。有趣的是,电化学数据表明双金属双螺旋 [M2L2]3+(M = Cu 或 Ag,L = L1 和 L2)内存在大量电子耦合,但单螺旋 [Ru2L2(terpy)2]4+ 系统则不然。