Influence of the Counteranion on the Formation of Polymeric Networks by Metal Complexes of Hexamethylenebis(acetamide)

摘要

An investigation into the anion dependence of the network-fonning ability of metal complexes of hexamethylenebis- (acetamide), CH3CONH(CHV~COCH3 (HMBA), has resulted in the X-ray characterization of the compounds [CO(HMBA)3][Co(NCS)4], I, [Nd(HMBA)3][Nd(NO3)6Jo2CHCI3, 2, [CO(HMBA)3][HgC4], 3, and [Mn(HMBA)3]- [HgBr4Jo3CHCI3, 4. The structures of compounds I, 3, and 4 each comprise cationic frameworks formed by the bridging action of HMBA ligands binding octahedrally to the cobalt or manganese centers and, in the cases of 3 and 4, the formation of tetrahedral Hg~2- anions by transfer of the respective halide ions from Co or Mn to Hg. Complete anion (NO3-) transfer between Nd centers is also a key factor in the structure of 2, which forms a cationic 3-D network of HMBA-bridged octahedrally coordinated Nd centers with occluded [Nd(NO3)6]3- anions. These types of inter-metal-anion transfer, with consequent complex counteranion formation, appear to facilitate the network-fonning ability of the metal-HMBA cationic arrays.