Three new Cu(Ⅱ)-Ln(Ⅲ) heterometallic coordination polymers based on two N-heterocyclic carboxylic ligands, {[LnCu(LI)2(L2)(H2O)2]· mH20},, (Ln = La(1), Nd(2), Gd(3), m = 2 (for 1), 1 (for 2, 3), H2L1 = quinolinic acid, HE2 = nico- tinic acid), have been synthesized and characterized. 1 has a two-dimensional (2D) layer structure with a Schlifli symbol of (44.62), while complexes 2 and 3 are isostructural and have three-dimensional (3D) structures with a Schlafli symbol of (3.4.5)2(32.42.52.6]4.74.83.9)(32.63.7) of 3-nodal net. Magnetic investigations suggest that antiferromagnetic coupling exists be- tween NdIn and Cun in 2, while weak ferromagnetic coupling between GdⅢ and CuⅡ in 3. The difference of magnetic properties between 2 and 3 has been discussed.
LIU SuiJun SONG WeiChao XUE Li HAN SongDe ZENG YongFei WANG LiFu BU XianHe
Two new Cu(II) coordination polymers, [Cu(FDA)(BPY)(H20)]n (1) and {[Cu(FDA)(BPY)(H2O)].2H2O}n (2) (H2FDA = 2,5-furandicarboxylic acid, BPY = 2,2'-bipyridine), have been synthesized and structurally characterized by single-crystal X-ray diffraction as well as elemental analysis and IR. Compound 1 crystallizes in monoclinic, space group P21/c, with a = 7.5915(15), b = 8.4050(17), c = 24.204(6) A, β = 99.05(3)°, V= 1525.1(6) A3, Dc = 1.706 g/crn3, C16HI2CuN206, Mr = 391.82, F(000) = 796, μ(MoKa) = 1.470 mm-l, Z = 4, R = 0.0633 and wR = 0.1059 for 2389 observed reflections (1 〉 2a(I)), R = 0.0738, and wR = 0.1098 for all data. Complex 2 belongs to triclinic space group PI with a = 8.8660(18), b = 8.9112(18), c = 12.525(3) A, a = 88.41(3), β = 69.38(3), γ = 66.95(3)°, V = 845.2(3) A3, Dc = 1.681 g/cm3, CI6HI6CuN2Os, Mr. = 427.85, F(000) = 438, μ(MoKα) = 1.342 mm-1, Z = 2, R = 0.0290 and wR = 0.0690 for 2767 observed reflections (I 〉 2σ(I)), R = 0.0329 and wR = 0.0706 for all data. Complexes 1 and 2 are both coordination polymers with one-dimensional chain structures bridged by the protonated FDA ligands, which are assembled into three-dimensional supramolecular structures through hydrogen bonding interactions and π-π packing interactions between the chains.
Three new CuⅡ coordination polymers,[Cu2(oba)2(H2O)(DMF)].3H2O(1),[Cu4(oba)4(DMF)4].4H2O.DMF(2) and [Cu2(oba)(hmp)2](3)(H2oba = 4,4'-oxybis(benzoic acid),Hhmp = 2-pyridine methanol,DMF = N,N'-dimethylformamide) were synthesized by solvothermal reactions and characterized by single-crystal X-ray diffraction.Both complexes 1 and 2 take three-dimensional(3D) three-fold interpenetrating PtS topology with 1D channels.In complex 3,Cu4 clusters were formed by the chelating hmp ligands,and then the clusters were further linked by oba ligands to form a 3D three-fold interpenetrating dia topology network.For 2,N2 sorption shows type I isotherm with BET surface areas of 562 m2 g-1 and Langmuir surface area of 747 m2 g-1,respectively.At 77 and 87 K,the hydrogen uptakes of complex 2 are 0.89 wt% and 0.57 wt%,respectively.Magnetic investigation showed the ferromagnetic coupling between CuII ions and very weak antiferromagnetic interaction between Cu4 clusters in complex 3.
Three new cobalt complexes, {[Co5(tci)2(bimb)3(μ3-O)2(H2O)2]·3DMF·4H2O}n(1), {[Co3(tci)2(bib)]·2DMF·2H2O}n (2) and {[Co(Htci)(bpea)0.5]-H2O}n (3) (H3tci = tris(2-carboxyethyl)isocyanurate, bimb = 4,4'-bis(imidazol-l-yl)biphenyl, bib = 1,4-bis(imidazol-l-yl)benzene, bpea = 1,2-bis(4-pyridyl)ethane, DMF = N,N'-dimethylformamide), have been successfully synthesized through the assembly of Co(If) ions, H3tci and different N-donor ligands, respectively. All complexes were structurally characterized by single crystal X-ray diffraction, elemental analyses, IR spectra, thermogravimetric (TG) analyses and X-ray powder diffraction (XRPD). Complex 1 exhibits a 3D three-fold parallel interpenetrated 3D · 3D structure with (65.8) CdSO4 topology. Complex 2 is built from [Co3(μ/2-Ocarboxyl)2(CO2)4] clusters and linear bib ligands, displaying a two-fold par- allel interpenetrated (3,8)-connected (4^3)2(4^6.6^18·8^4) topology, while complex 3 is a 3D pillar-layered structure involving an in- finite -Co-(μ2-Ocarboxyl)(CO2)-Co-chain. The diverse structures of the three complexes indicate that the skeletons of different N-donor ligands play an important role in the assembly of such different frameworks. In addition, magnetic investigation indi- cates that besides spin-orbit coupling of Co(II) ions, there exist antiferromagnetic exchange interactions in Co5 and Co3 clus- ters of 1 and 2, respectively.
Coordination polymers (or metal-organic frameworks, MOFs), as one of the essences of crystal engineering and coordination chemistry, have attracted considerable atten-tion from chemists,