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An unprecedented 3D framework, [Ag(Ag6(C2-Me-(Mepdz)2)3(CH3CN))2](ClO4)13, has been synthesized by using a ligand with both rigid pyridazine and flexible hydrazone segments, which represents to the best of our knowledge, the first example of metallosupramolecule built by the triple-stranded helixes sharing the same penta-silver core.

The sulfamide derivative of triphenylmethanol, 3-[hydroxy(diphenyl)methyl]benzenesulfonamide (H2NSO2Ph)Ph2COH was synthesized and, alongside with the parent triphenylmethanol and triphenylmethylamine, was investigated for selective interactions with crown ethers of different dimensionality (12-18-membered cycles). The molecule of 12-crown-4 (12C4) appeared to be the best candidate for Ph3COH, Ph3CNH2 and Ph3CNH3·NCS, while (H2NSO2Ph)Ph2COH forms the complex exclusively with 18-crown-6 (18C6). The triphenylammonia trifluoroacetate, Ph3CNH3·CF3COO, selectively forms the complex only with 2-methoxyethanol. The crystalline products of the compositions (Ph3COH)2·12C4, (Ph3CNH2)2·12C4, (Ph3CNH3·NCS)2·12C4, [(H2NSO2Ph)Ph2COH]2·18C6 and Ph3CNH3·CF3COO CH3OCH2CH2OH were obtained and studied by X-ray single crystal diffraction.

Two synthetic pathways, the interaction of Nb2O5 or Ta2O5 with an aqueous solution of hydrofluoric acid, HF, in the presence of 18-crown-6 (18C6), 15-crown-5 (15C5), benzo-15-crown-5 (B15C5) or benzo-12-crown-4 (B12C4), and the direct interaction of the corresponding pentafluorides, MF5 (M = Ta, Nb), in the presence of HF with the same crown ethers result in crystalline complexes of the same composition, [18C6 · H3O][NbF6] (1), [18C6 · H3O][TaF6] (2), [15C5 · H5O2][TaF6] (3), [(B15C5)2 · H5O2][(B15C5)2 · H3O][TaF6]2 (4) and [(B12C4)2 · H3O][TaF6] (5). Complexes 1–5 were identified by elemental and X-ray structural analysis. Compounds 1 and 2 are isostructural, with the [H3O]+ oxonium ion embedded in one crown molecule via OH⋯O hydrogen bonds. Complexes 3–5 represent sandwich-like adducts with the [H3O]+ or [H5O2]+ cations encapsulated. A plethora of weak C–H⋯F interactions with NbF 6 - and TaF 6 - anions is responsible for the extended supramolecular architectures.

The crystal structures of [(cys-syn-cys-dicyclohexano-18-crown-6 · H3O)][TaF6] and [(cys-syn-cys-dicyclohexano-18-crown-6 · H3O)][NbF6] complex compounds are determined using X-ray diffraction analysis. The tantalum complex has two polymorphic modifications, namely, the monoclinic (I) and triclinic (II) modifications. The unit cell parameters of these compounds are as follows: a = 8.507(4) A, b = 11.947(5) A, c = 27.392(12) A, β = 93.11(1)°, Z = 4, and space group P21/n for modification I; and a = 10.828(1) A, b = 11.204(1) A, c = 12.378(1) A, α = 72.12(1)°, β = 79.40(1)°, γ = 73.70(1)°, Z = 2, and space group P-1 for modification II. The triclinic niobium complex [(cys-syn-cys-dicyclohexano-18-crown-6 · H3O)][NbF6] (III) with the unit cell parameters a = 10.796(3) A, b = 11.183(3) A, c = 12.352(3) A, α = 72.364(5)°, β = 79.577(5)°, γ = 73.773(4)°, Z = 2, and space group P-1 is isostructural with tantalum complex II. The structures of all three complexes are ionic in character. The oxonium cation in complexes I–III is encapsulated by the crown ether and thus forms one ordinary and two bifurcated hydrogen bonds with the oxygen atoms of the crown ether. This macrocyclic cation is bound to the anions through the C-H...F contacts (H...F, 2.48–2.58 A). The conformation of the macrocycle in complex I differs substantially from that in complex II (III).

The reaction of thionicotinamide (3-thioamidopyridine) with 18-membered crown ethers, 18-crown-6 (18C6), benzo-18-crown-6 (B18C6) and cis–anti–cis-dicyclohexyl-18-crown-6 (D18C6) results in the molecular complexes of 1:1 ratio for 18C6 (complex 1) and B18C6 (complex 2) and monohydrate of 2:1:1 ratio for D18C6 (complex 3), respectively. The complexes are sustained by combination of N–H⋯O, O–H⋯N and C–H⋯O hydrogen bonds, and the components are associated into molecular adduct (1) or infinite chain (2 and 3).

A microporous material constructed by π-π interaction of a twisted H-shape poly-aromatic molecule, 1,4-bis(3,6-diphenylpyridazin-4-yl)benzene ( 1 ) was synthesized and X-ray quality crystals were isolated. The intermolecular distances between the various aromatic rings are within the range of 3.4 ∼ 3.7 A, which indicate intermolecular π-π interactions. Hexagonal channels with pores of 13 A width along the c-axis were observed. Interstitial H2O and MeOH molecules were located within each porous channel.

Two cuprous complexes Cu(L1)(PPh3)I (1) and Cu(L2)(PPh3)I (2) were obtained by reaction of Cu(PPh3)3I (PPh3 = triphenylphosphine) with two different α-diimine ligands L 1 (3,5-di(2′-pyridyl)-4-amin...

The reaction of 3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine (4-PTA) with trimesic acid (TMA) in methanol solution in a 1.5:1 mole proportion affords molecular complex 1 . The structure was confirmed by single crystal X-ray diffraction study. The compound crystallizes in the triclinic space group P-1 with a = 9.7625(11), b = 11.7298(13), c = 13.0734(13), α = 68.849(10)°, β = 72.701(8)°, γ = 83.937(9)° and Z = 2. The crystal structure of 1 shows hydrogen bonding between 4-PTA and TMA, and the presence of an interstitial H2O molecule in the crystal. The zigzag 1-dimensional framework was constructed by the intermolecular hydrogen bond containing O–H…N, O–H…O and C–H…O interactions. The π–π interactions are the non-covalent forces operating between the pyridine ring in 4-PTA and benzene ring in TMA to generate 3-dimensional network.