Department of Chemistry, Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan.
Inorg Chem. 2012 Jul 2;51(13):7022-4. doi: 10.1021/ic301140z. Epub 2012 Jun 14.
Anion-controlled circular dichroism (CD) spectral changes in Hg(2+) complexes with a chiral bidentate ligand are reported. Although the Hg(CF(3)SO(3))(2) and Hg(CF(3)CO(2))(2) complexes with (R)-(-)-1-(naphthalen-1-yl)-N,N-bis(pyridin-4-ylmethyl)ethanamine, (R)-(-)-1, show significant CD spectral changes, no CD spectral changes were observed in the HgCl(2), HgBr(2), Hg(CN)(2), or Hg(CH(3)CO(2))(2) complexes. X-ray analysis indicates that both the (R)-(-)-1-Hg(CF(3)SO(3))(2) and (R)-(-)-1-HgCl(2) complexes form a coordination polymer and a discrete 2:3 [=(R)-(-)-1/HgCl(2)] complex with a figure-eight structure. X-ray crystallography revealed that (i) the Hg-Hg distances bridged by anions vary depending on the anions used and (ii) a coordination polymer cannot be formed when the Hg-Hg distances are too short. Therefore, the formation of a coordination polymer is required to give the observed significant CD spectral changes.
报道了手性双齿配体与 Hg(2+) 配合物的阴离子控制圆二色性 (CD) 光谱变化。尽管 Hg(CF3SO3)2 和 Hg(CF3CO2)2 与 (R)-(-)-1-(萘-1-基)-N,N-双(吡啶-4-基甲基)乙胺（(R)-(-)-1）形成配合物时，会发生显著的 CD 光谱变化，但 HgCl2、HgBr2、Hg(CN)2 或 Hg(CH3CO2)2 形成的配合物则没有 CD 光谱变化。X 射线分析表明，(R)-(-)-1-Hg(CF3SO3)2 和 (R)-(-)-1-HgCl2 配合物均形成了配位聚合物和具有“8”字形结构的离散 2:3 [=(R)-(-)-1/HgCl2] 配合物。X 射线晶体学揭示：（i）阴离子桥接的 Hg-Hg 距离取决于所使用的阴离子；（ii）当 Hg-Hg 距离过短时，无法形成配位聚合物。因此，形成配位聚合物是产生观察到的显著 CD 光谱变化的必要条件。
