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Abstract: A novel 1D square-helical coordination polymer [ZnI2(μ2-dppe)] n (1) was synthesized by the reaction of ZnI2 with 1,2-bis(diphenylphosphino)ethane (dppe), while zigzag chains [MX2(μ2-dppe)] n were obtained by using smaller anions (Cl− and Br−) and larger metal ions (Cd2+ and Hg2+). [Copyright &y& Elsevier]

A coordination polymeric crystal 1 was successfully synthesized from H 4 L (5,5′-(1,4-phenylenebis (methoxy))diisophthalic acid), bidpe (4,4′-bis(lmidazolyl)diphenyl ether), and Zn(NO 3) 2 ·6H 2 O under solvothermal conditions, and characterized by single-crystal X-ray diffraction. Then, two new crystals 1 Fe and 1 Cu were obtained with metal ion exchange when 1 was dipped into the DMF solution for FeCl 2 and CuCl 2 , respectively. The exchange process demonstrated that the high valence metal ion with strong acidity could be destroyed the structure of the crystals. Therefore, it should be exchanged with lower valence ion and then oxidized to the high valence state, which could be a feasible way to obtain the crystals with high valence metal ions. Further, the magnetic property and the synergistic CO 2 conversion with epoxide for 1 Fe and 1 Cu were also investigated, and the results shown that 1 Fe could be regarded as a potential catalyst for this conversion. Three two dimensional two-fold interpenetrated MOFs 1 , 1 Fe and 1 Cu were successfully synthesized via solvothermal or post-synthetic modification. 1 Fe and 1 Cu shown excellent abilities for catalyzed cycloaddition of CO 2 to epoxides. [Display omitted] 1. Three novel dimensional MOFs 1 , 1 Fe and 1 Cu , have been synthesized via solvent-thermal treatment and post-synthetic exchange approach. 2. Zn(II) ions were exchange with Fe(III) ions in 1 Fe. But, due to the strong acidity of Fe(III) ions could destroy the crystal framework, the exchange only could be happen when 1 was dipped into the freshly FeCl 2 -DMF solution. 3. Variable-temperature magnetic studies indicate that 1 Fe contains the weak ferromagnetic chain while 1 Cu contains the weak antiferromagnetic (AF) interactions. 4. The catalytic properties of 1 , 1 Fe and 1 Cu for epoxides' cycloaddition reactions with CO 2 , and the results shown that 1 Fe and 1 Cu could be good catalysts for this reaction. [ABSTRACT FROM AUTHOR]

Abstract: A series of group 12 metal coordination polymers with 1,2-bis(diphenylphosphino)ethane dioxide (dppeO2), {[ZnCl2(μ-dppeO2)]·CH2Cl2} n (1·CH2Cl2), [ZnBr2(μ-dppeO2)] n (2), [CdI2(μ-dppeO2)] n (4), [(HgI2)2(μ-dppeO2)] n (5), [Zn(SCN)(μ-SCN)(μ-dppeO2)] n (6), and [Cd(NO3)(μ-SCN)(μ-dppeO2)] n (7), have been synthesized and structurally characterized. The structures of the compounds are all based on an infinite 1D chain constructed by four-coordinate metal ions and dppeO2 ligands adopting the trans bridging coordination fashion. In the coordination polymers 1, 2 and 4, the halide ions act as terminal ligands, leading to discrete 1D chains with alternative MX2 and dppeO2 repeating units. The mercury compound 5 features a unique square-wave-like inorganic chain –[Hg(1)–I–Hg(2)–I]–, and the 1D HgI2(μ-dppeO2) chains are further linked by HgI2 bridges to form a 3D network. In the thiocyanate-containing compounds 6 and 7, the 1D chains are linked by one (6) or two (7) bridging SCN– ions to result in 2D layered structures. Solid-state emission spectra of the coordination polymers show different variations compared to the free dppeO2 ligand, such as enhancement (1, 2, 6 and 7), shift (3 and 4) and quenching (5) upon metal coordination. [Copyright &y& Elsevier]