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A Pair of Co Supramolecular Isomers Based on Flexible Bis-Pyridyl-Bis-Amide and Angular Dicarboxylate Ligands.

Thermal reactions of cobalt(II) salts with flexible -bis(pyrid-3-ylmethyl)adipoamide () and angular 4,4'-sulfonyldibenzoic acid (HSDA) in HO and CHOH afforded a pair of supramolecular isomers: [Co()(SDA)], , and [Co()(SDA)]⋅CHOH⋅HO, . The structure of complex can be simplified as a one-dimensional (1D) looped chain with ligands penetrating into the middles of squares, forming a new type of self-catenated net with the (4⋅5)(4)(5) topology, whereas complex displays a 2-fold interpenetrated 2D net with the rare (4⋅6⋅8⋅10)(4)-2,6L1 topology. While both complexes and display antiferromagnetism with strong spin-orbital coupling, the antiferromagnetism of is accompanied by a cross-over behavior and probably a spin canting phenomenon.

One-Dimensional Mercury Halide Coordination Polymers Based on A Semi-Rigid -Donor Ligand: Reversible Structural Transformation.

Four one-dimensional (1D) mercury(II) halide coordination polymers have been synthesized by using a semi-rigid -donor ligand, 2,2'-(1,4-phenylene)-bis(-(pyridin-3-yl)acetamide) (1,4-pbpa). While [Hg(1,4-pbpa)Cl₂·CH₃OH], , forms a sinusoidal chain, the complexes [Hg(1,4-pbpa)X₂] (X = Cl, ; Br, ; I, ) are helical. The sinusoidal undergoes reversible structural transformation with helical upon removal and uptake of CH₃OH, which was accompanied with the conformation adjustment of the 1,4-pbpa ligand from anti-anti to syn-anti.

Metal and Ligand Effects on the Construction of Divalent Coordination Polymers Based on bis-Pyridyl-bis-amide and Polycarboxylate Ligands.

Ten coordination polymers constructed from divalent metal salts, polycarboxylic acids, and bis-pyridyl-bis-amide ligands with different donor atom positions and flexibility are reported. They were structurally characterized by single-crystal X-ray diffraction. The ten coordination polymers are as follows: () {[Ni()(3,5-PDA)(H₂O)₃]·2H₂O} ( = ,'-di(3-pyridyl)suberoamide, 3,5-H₂PDA = 3,5-pyridinedicarboxylic acid); () {[Ni₂()₂(1,3,5-HBTC)₂(H₂O)₄]·H₂O} (1,3,5-H₃BTC = 1,3,5-benzenetricarboxylic acid); () {[Ni()(5--IPA)(H₂O)₂]·2H₂O} ( = ,'-di(3-pyridyl)adipoamide, 5--H₂IPA = 5--butylisophthalic acid); () [Ni()(5--IPA)] ( = ,'-di(4-pyridyl)adipoamide); () [Co()(1,3,5-HBTC)(H₂O)]; () {[Co₃()₃(1,3,5-BTC)₂(H₂O)₂]·6H₂O}; () [Cu()(AIPA)] ( = ,'-bis(3-pyridinyl)terephthalamide, H₂AIPA = 5-acetamido isophthalic acid); () {[Cu()(AIPA)]·MeOH}; () {[Zn()(AIPA)]·2H₂O}; and () {[Zn()(AIPA)]·2H₂O}.

Hg(II) Coordination Polymers Based on N,N'-bis(pyridine-4-yl)formamidine.

Reactions of -bis(pyridine-4-yl)formamidine (4-Hpyf) with HgX₂ (X = Cl, Br, and I) afforded the formamidinate complex {[Hg(4-pyf)₂]·(THF)}, 1, and the formamidine complexes {[HgX₂(4-Hpyf)]·(MeCN)} (X = Br, 2; I, 3), which have been structurally characterized by X-ray crystallography. Complex 1 is a 2D layer with the {4⁴·6²}-sql topology and complexes 2 and 3 are helical chains. While the helical chains of 2 are linked through N⁻H···Br hydrogen bonds, those of 3 are linked through self-complementary double N⁻H···N hydrogen bonds, resulting in 2D supramolecular structures.