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In the structure of the title salt, {[Ba(μ3-C3H2N3O2)2(μ-H2O)(H2O)]·H2O}n, the barium ion and all three oxygen atoms of the water molecules reside on a mirror plane. The hydrogen atoms of the bridging water and the solvate water molecules are arranged across a mirror plane whereas all atoms of the monodentate aqua ligand are situated on this mirror plane. The distorted ninefold coordination of the Ba ions is completed with four nitroso-, two carbonyl- and three aqua-O atoms at the distances of 2.763 (3)–2.961 (4) Å and it is best described as tricapped trigonal prism. The three-dimensional framework structure is formed by face-sharing of the trigonal prisms, via μ-nitroso- and μ-aqua-O atoms, and also by the bridging coordination of the anions via carbonyl-O atoms occupying two out of the three cap positions. The solvate water molecules populate the crystal channels and facilitate a set of four directional hydrogen bonds. The principal Ba–carbamoylcyanonitrosomethanido linkage reveals a rare example of the inherently polar binodal six- and three-coordinated bipartite topology (three-letter notation sit). It suggests that small resonance-stabilized cyanonitroso anions can be utilized as bridging ligands for the supramolecular synthesis of MOF solids. Such an outcome may be anticipated for a broader range of hard Lewis acidic alkaline earth metal ions, which perfectly match the coordination preferences of highly nucleophilic nitroso-O atoms. Thermal analysis reveals two-stage dehydration of the title compound (383 and 473 K) followed by decomposition with release of CO2, HCN and H2O at 558 K. [ABSTRACT FROM AUTHOR]

In the structure of the title co-crystal, C3H3N3O2·C5H8N2, the components are linked by a set of directional O--H...N, N--H...O, N--H...N and C--H...O hydrogen bonds to yield a two-dimensional mono-periodic arrangement. The structure propagates in the third dimension by extensive π-π stacking interactions of nearly parallel molecules of the two components, following an alternating sequence. The primary structure-defining interaction is very strong oxime-OH donor to pyrazole-N acceptor hydrogen bond [O...N = 2.587 (2) Å ], while the significance of weaker hydrogen bonds and π-π stacking interactions is comparable. The distinct structural roles of different kinds of interactions agree with the results of a Hirshfeld surface analysis and calculated interaction energies. The title compound provides insights into co-crystals of active agrochemical molecules and features the rational integration in one structure of a fungicide, C3H3N3O2, and a second active component, C5H8N2, known for alleviation the toxic effects of fungicides on plants. The material appears to be well suited for practical uses, being non-volatile, air-stable, water-soluble, but neither hygroscopic nor efflorescent. [ABSTRACT FROM AUTHOR]

Seventeen porphyrins are synthesized to explore the use of porphyrins tethered to silicon via carbosilane linkages as well as two high-temperature processing methods are developed for rapid (minutes), facile covalent attachment to Si platforms. The findings indicate that porphyrins bearing a variety of functional groups can be covalently attached to Si via high temperature processing.

1,2,4-Triazol-4-yl-acetic acid (trGly-H) has been used as a heterobifunctional ligand for preparing homometallic (AgI) and heterometallic (AgI/UVI) coordination polymers under hydrothermal conditions. Four coordination compounds, [Ag4(trGly)4]·2H2O (1), [Ag4(trGly)2(trGly-H)2](NO3)2·2H2O (2), [(UO2){Ag4(trGly)4(NO3)2(H2O)}]·4H2O (3) and [(UO2)2{Ag6(trGly)10}]·7H2O (4), have been synthesized and structurally characterized. Compounds 1 and 2 are similar and consist of tetranuclear [Ag4(tr)4(COO)2] secondary building units (SBUs) supported by four [–N–N–] triazole bridges in the {Ag4}-cluster plane and two carboxylate functions in the axial positions, which link the rhomboid units together into a thick layer. Addition of uranyl ions in the reaction system leads to compounds 3 and 4, where tr- and –COO−-functional groups are differentiated by their coordination role: tr binds Ag+ ions, while –COO− interacts with UO22+. The crystal structure of 3 includes tetranuclear [Ag4(tr)4(NO3)2] units linked by four [–N–N–] triazoles and two nitrate anions above and below the cluster core. In 3, uranium in a pentagonal bipyramidal {UO7} arrangement forms "cation–cation" interactions with AgI centers (the Ag⋯O＝U＝O distance is short, 2.600 Å). The 3D framework of compound 4 is constructed from hexanuclear [Ag6(tr)10] SBUs in a form of hexagonal twisted prisms that are further stacked into a column motif through argentophilic (Ag⋯Ag) interactions of 3.06 Å. To explore the AgNO3/trGly-H/UO2(NO3)2·6H2O system, the composition space diagram approach was employed. The defined crystallization fields of the compounds show that complex 3 is the dominant product, while 4 appears only in a high ligand concentration range. The thermal behavior and solid-state photoluminescence properties of the compounds have been investigated. [ABSTRACT FROM AUTHOR]

The synthesis of a family of redox-active molecules bearing a tripodal tether with three protected thiol groups is presented. A series of electrochemical studies designed to evaluate the redox characteristics and the electron-transfer and charge-dissipation rates of the self-assembled monolayers of the various thiol-derivatized complexes on Au is described.

The synthesis of a selection of porphyrins bearing benzylphosphonic acid, hexylphosphonic acid, and tripodal phosphonic acid groups are presented. The electrochemical characteristics of a porphyrin-tripodal phosphonic acid compound tethered to a SiO2 dielectric layer on a Si platform are described.

The methodologies for preparing diverse porphyrinic molecules bearing phenylphosphonic acid tethers for attachment to oxides are discussed. The foundation for the synthesis of diverse redox-active molecules suitable for attachment to a range of surfaces for studies of information storage is provided.

The title coordination polymer, {[Cu3(C4H4N3O9)3(SeO4)(OH)]·2H2O}n or ([Cu3(μ3-OH)(trgly)3(SeO4)]·2H2O), crystallizes in the monoclinic space group P21/c. The three independent Cu2+ cations adopt distorted square-pyramidal geometries with {O2N2+O} polyhedra. The three copper centres are bridged by a μ3-OH anion, leading to a triangular [Cu3(μ3-OH)] core. 2-(1,2,4-Triazol-4-yl)acetic acid (trgly-H) acts in a deprotonated form as a μ3-κ³N¹:N²:O ligand. The three triazolyl groups bridge three copper centres of the hydroxo-cluster in an N¹:N² mode, thus supporting the triangular geometry. The [Cu³(μ3-OH)(tr)3] clusters serve as secondary building units (SBUs). Each SBU can be regarded as a six-connected node, which is linked to six neighbouring triangles through carboxylate groups, generating a two-dimensional uninodal (3,6) coordination network. The selenate anion is bound in a μ3-κ³O¹:O²:O³ fashion to the trinuclear copper platform. The [Cu3(OH)(trgly)3(SeO4)] coordination layers and guest water molecules are linked together by numerous O--H···O and C--H···O hydrogen bonds, leading to a three-dimensional structure. [ABSTRACT FROM AUTHOR]

The crystal structure of the title mol­ecular complex, [Ag2{VO2F2}2(C13H17N3O2)4]·4H2O, supported by the heterofunctional ligand tr-ad-COOH [1-(1,2,4-triazol-4-yl)-3-carb­oxy­adamantane] is reported. Four 1,2,4-triazole groups of the ligand link two AgI atoms, as well as AgI and VV centres, forming the heterobimetallic coordination cluster {AgI2(VVO2F2)2(tr)4}. VV exists as a vanadium oxofluoride anion and possesses a distorted trigonal–bipyramidal coordination environment [VO2F2N]. A carb­oxy­lic acid functional group of the ligand stays in a neutral form and is involved in hydrogen bonding with solvent water mol­ecules and VO2F2− ions of adjacent mol­ecules. The extended hydrogen-bonding network is responsible for the crystal packing in the structure. [ABSTRACT FROM AUTHOR]

The title Cu2+–chloride coordination polymer with the 4,4′-bi-1,2,4-triazole ligand (btr), [Cu4Cl8(C4H6N6)3]n, crystallizes in the non-centrosymmetric ortho­rhom­bic space group Fdd2. The two independent Cu2+ cations adopt distorted square-pyramidal geometries with {Cl2N2+Cl} coordination polyhedra. The metal atoms are bridged by μ-Cl anions forming left- and right-handed helical chains of sequence [–(μ-Cl)CuCl–]n along the c-axis direction. In the perpendicular directions, the btr ligands act in μ- and μ3– coordination modes in a 2:3 ratio. The μ-btr bridges connect neighboring helices of the same handedness, whereas the μ3-btr ligands link the helices of opposite handedness, leading to a racemic three-dimensional framework. The structure is consolidated by weak C—H· · ·Cl and C—H· · ·N inter­actions. [ABSTRACT FROM AUTHOR]

A bitopic ligand, 4-(3,5-dimethylpyrazol-4-yl)-1,2,4-triazole (Hpz-tr) (1), containing two different heterocyclic moieties was employed for the design of copper(II)-molybdate solids under hydrothermal conditions. In the multicomponent CuII/Hpz-tr/MoVI system, a diverse set of coordination hybrids, [Cu(Hpz-tr)2SO4]·3H2O (2), [Cu(Hpz-tr)Mo3O10] (3), [Cu4(OH)4(Hpz-tr)4Mo8O26]·6H2O (4), [Cu(Hpz-tr)2Mo4O13] (5), and [Mo2O6(Hpz-tr)]·H2O (6), was prepared and characterized. A systematic investigation of these systems in the form of a ternary crystallization diagram approach was utilized to show the influence of the molar ratios of starting reagents, the metal (CuII and MoVI) sources, the temperature, etc., on the reaction products outcome. Complexes 2-4 dominate throughout a wide crystallization range of the composition triangle, while the other two compounds 5 and 6 crystallize as minor phases in a narrow concentration range. In the crystal structures of 2-6, the organic ligand behaves as a short [N-N]-triazole linker between metal centers Cu···Cu in 2-4, Cu···Mo in 5, and Mo···Mo in 6, while the pyrazolyl function remains uncoordinated. This is the reason for the exceptional formation of low-dimensional coordination motifs: 1D for 2, 4, and 6 and 2D for 3 and 5. In all cases, the pyrazolyl group is involved in H bonding (H-donor/H-acceptor) and is responsible for π-π stacking, thus connecting the chain and layer structures in more complicated H-bonding architectures. These compounds possess moderate thermal stability up to 250-300 °C. The magnetic measurements were performed for 2-4, revealing in all three cases antiferromagnetic exchange interactions between neighboring CuII centers and long-range order with a net moment below Tc of 13 K for compound 4. [ABSTRACT FROM AUTHOR]