A new 1D chain coordination polymer [Cd(dpq)(ox)0.5Cl]n (1) (dpq=dipyrido[3,2-d:2′,3′-f]quinoxaline and ox=oxalate) has been hydrothermally synthesized and structurally characterized by elemental analysis, IR and single crystal X-ray diffraction analysis. Compound 1 (CdClC15H8N4O2): monoclinic, space group P21/c, a=0.854 04(5) nm, b=2.094 90(13) nm, c=0.839 22(5) nm, Z=4, V=1.438(15) nm3, Mr=424.11, Dc=1.959 g·cm-3, F(000)=828.0, μ= 1.719 mm-1, S=1.028, the final R=0.025 8 and wR=0.057 5. The crystal structure analysis indicates that the cadmium ion is coordinated by two oxygen atoms from a oxalate, two chelating nitrogen atoms from a dpq molecule and two Cl-anions. The adjacent Cd(Ⅱ) ions are linked by Cl-anions and oxalate ligands in alternate sequence to form a 1D chain coordination polymer and the adjacent chains are further connected by π-π stacking interactions to form a 2D supramolecular network. Moreover, the title compound exhibits blue emission in the solid state at room temperature.
Four coordination polymers based on two bis-pyridyl-bis-amide ligands and three aromatic dicarboxylates with different substituent groups, namely, [Co（3-bpcb）x.5（NPH）（H20）]＂ 4H20 （1）, [Co（3-bpcb）（NIPH）] （2）, [Co（3-bpcb）0.5（5-H2AIP）]＂ 2H20 （3）, [Co（3-bpcd）0.5（5-H2AIP）（H20）]＂ 2H20 （4） [3-bpcb = N,N＇-bis（3-pyridinecarboxamide）-l,4-benzene, 3-bpcd = N,N＇-bis（3- pyridine）cyclohexane-l,4-dicarboxamide, H2NPH = 3-nitrophthalic acid, H2NIPH = 5-nitroisophthalic acid, 5-HaAIP = 5-aminoisophthalic acid] have been synthetized under hydrothermal conditions. Complex 1 displays a one dimensional （1D） chain based on the binuclear [Co2（NPH）2] units and 3-bpeb ligands, which is extended into a three dimensional （3D） supra- molecular framework through hydrogen bonding and n-n stacking interactions. In complex 2, the （3,5）-connected two dimen- sional （2D） layers are constructed from 1D Co-NIPH chains and bidentate-bridging 3-bpeb ligands. Complex 3 is a 2D double layer based on Co-5-H2AIP 2D layers and 3-bpeb pillars. Complex 4 also displays a 2D network, which is constructed from the Co-5-H2AIP 1D double chains and 3-bpcd ligands. Finally, complexes 2--4 are extended into 3D supramolecular frame- works by hydrogen bonding or n-re stacking interactions. The substituent groups of dicarboxylates play an important role in the assembly and structures of the title complexes. In addition, the fluorescent properties of complexes 1-4 and the electrochemi- cal behaviors of 3 and 4 at room temperature have been investigated.
WANG XiuLiMU BaoLIN HongYanYANG SongLIU GuoChengTIAN AiXiangZHANG JuWen
