Hsiu-Yi He

Structural directing roles of isomeric phenylenediacetate ligands in the formation of coordination networks based on flexible N,N′-di(3-pyridyl)suberoamide

Reactions of the flexible N,N′-di(3-pyridyl)suberoamide (L) with Cu(II) salts in the presence of the isomeric phenylenediacetic acids under hydrothermal conditions afforded three new coordination networks, {[Cu(L)(1,2-pda)]·H2O}n (1,2-H2pda = 1,2-phenylenediacetic acid), 1, {[Cu(L)(1,3-pda)]·2H2O}n (1,3- H2pda = 1,3-phenylenediacetic acid), 2, and {[Cu(L)(1,4-pda)]·2H2O}n (1,4-H2pda = 1,4-phenylenediacetic acid), 3, which have been structurally characterized by X-ray crystallography. Complex 1 forms a single 3,5-coordinated 3D net with the (42·65·83)(42·6)-3,5T1 topology, which can be further simplified as a 6-coordinated (412·63)-pcu topology. Complex 2 is a 5-fold interpenetrated 3D structure with the (65·8)-cds topology, which exhibits the maximum number of interpenetration presently known for cds and complex 3 is the first 1D self-catenated coordination network. The ligand isomerism of the phenylenediacetate ligands is important in determining the structural types of the Cu(II) coordination networks based on the flexible L ligands.

Construction of N,N′-di(3-pyridyl)adipoamide-based Zn(II) and Cd(II) coordination networks by tuning the isomeric effect of polycarboxylate ligands

Eight new Zn(II) and Cd(II) coordination networks containing N,N′-di(3-pyridyl)adipoamide (L) and polycarboxylate ligands, {[Zn2(2,5-PDC)2(L)(H2O)2]·2H2O}∞ (H2PDC = 2,5-pyridinedicarboxylic acid), 1, [Zn2(2,6-PDC)2(L)]∞, 2, {[Zn2(3,4-PDC)2(L)(H2O)6]·4H2O}∞, 3, {[Cd(2,6-PDC)(L)(H2O)]·4H2O}∞, 4, [Zn(1,3,5-HBTC)()]∞ (H3BTC = benzenetricarboxylic acid), 5, {[Cd(1,2,3-HBTC)(L)(H2O)]·H2O}∞, 6, {[Cd2(1,3,5-HBTC)2(L)(H2O)2]·2H2O}∞, 7, and {[Zn3(1,2,4-BTC)2(L)(H2O)4]·4H2O}∞, 8, have been synthesized by hydrothermal reactions and characterized by single crystal X-ray crystallography. Structural analysis reveals that 1 and 2 form pleated hcb layers with 1D helical chains, in which the layers of 1 interdigitate with each other and those of 2 are linked by the π–π stacking interactions. Complexes 3 and 4 exhibit 1D ladders with single and double rungs, respectively, whereas 5 shows a 2D pleated net with the sql topology, 6 displays a 3D dia coordination network and 7 forms a 2D structure with the (63)(66)-3,4L88 topology. The BTC3− ligands in 8 adopt the μ4-bonding modes, resulting in a 3D coordination network with the rare (65·8)-hxg-d-4-P2/c topology. The various bonding modes, the ligand-isomerism of the polycarboxylate ligands and the identity of the metal center play important roles in determining the structural diversity. Their thermal and luminescent properties are also discussed.

Entanglement in Co(II) coordination networks: polycatenation from single net to 2-fold and 3-fold interpenetrated nets

The synthesis, structures and properties of six coordination networks based on N,N′-di(4-pyridyl)suberoamide (L) and angular dicarboxylate ligands, {[Co(L)(MBA)]·2H2O}n (H2MBA = diphenylmethane-4,4′-dicarboxylic acid), 1, {[Co(L)0.5(MBA)]·CH3OH}n, 2, [Co(L)0.5(MBA)]n, 3, {[Co2(L)(OBA)2]·7CH3OH}n [H2OBA = 4,4′-oxybis(benzoic acid)], 4, {[Co(L)(hfipbb)]·2H2O}n [H2hfipbb = 4,4′-(hexafluoroisopropylidene)bis(benzoic acid)], 5, and {[Co(L)(SDA)]·H2O}n (H2SDA = 4,4′-sulfonyldibenzoic acid), 6, are reported. Complex 1 is a 1D → 2D polycatenane derived from the helical channels, whereas both complexes 2 and 3 show 2D layers with the (42·68·8·104)(4)2-2,6L1 topology, which are further entangled to form a 2-fold 2D → 2D interpenetration network and a 2D → 3D inclined polycatenation network, respectively, and complex 4 shows a 3-fold 3D → 3D interpenetration network with the (412·63)-pcu topology. The unusual topological features of 5 and 6 consist of 2- and 3-fold interpenetrated layers with the (44·62)-sql topology, which are further catenated to the two such adjacent sheets in parallel and uniform fashions to give 2D → 3D polycatenated networks. Complexes 1, 5 and 6 represent unique examples that the angular dicarboxylate ligands show significant effect on the degree of interpenetration of polycatenation coordination networks with interpenetrating modes. The CO2 capture is preferable to N2 and H2 in the gas sorption for the desolvated product of 4.

Homo- and heterometallic coordination networks based on linear trinuclear Co(II) units: syntheses, structures and magnetic properties

Two three-dimensional (3D) coordination networks, [Co3(1,4-BDC)3(L1)]∞ (L1 = N,N′-bis(3-pyridinyl)-1,4-benzenedicarboxamide; 1,4-H2BDC = 1,4-benzenedicarboxylic acid), 1, and [K2Co3(L2)4]∞ (H2L2 = 5-acetamidoisophthalic acid), 2, have been synthesized by hydrothermal reactions and characterized by single crystal X-ray crystallography. Complex 1 consists of linear trinuclear Co(II) centers, which are linked by the 1,4-BDC− and L1 ligands to form a rare (1 + 3) self-catenated 3D net with the new (36,410,511,6) topology, and complex 2 reveals a 3p–3d heterometallic coordination network based on linear trinuclear Co(II) and dinuclear K(I) centers bridged by the μ6-L2 ligands, forming a 4,4,8-connected trinodal net with the new (414·610·84)(42·64)(44·62) topology. The linear trinuclear Co(II) centers in 1 adopt the square pyramidal–octahedral–square pyramidal geometries, whereas those in 2 are tetrahedral–octahedral–tetrahedral. Both of the complexes exhibit paramagnetism that is consistent with the Curie–Weiss law between 60 and 300 K. The effective magnetic moments (〈μeff〉) of both complexes are larger than the estimated value of 6.71 μB/f.u., revealing the spin–orbit couplings that are invoked by the different distorted geometries of the linear trinuclear Co(II) centers. The dinuclear K(I) centers in 2 weaken the magnetic coupling, and reduce the antiferromagnetic ordering at 6 K.

Stepwise formation of heteronuclear coordination networks based on quadruple-bonded dimolybdenum units containing formamidinate ligands

Reactions of [Mo2(4-pyf)4] (4-Hpyf = 4-pyridylformamidine) with HgX2 (X = Cl, Br and I) afforded the first 2D and 3D heteronuclear coordination networks based on quadruple-bonded dimolybdenum units.