Ag(I)Based Tectons for the Construction of Helical and meso Helical Hydrogen-Bonded Coordination Networks (original) (raw)
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Journal of Molecular Structure, 2011
Construction of AgX (X À = ClO À 4 and BF À 4 ) with highly flexible N,N,N 0 ,N 0 -tetrakis(ethylisonicotinoyl)ethylendiamine (L) has been scrutinized for the weak argentophilic, Ag anion, and AgÁsolvent interactions. All such complexes afford coordination polymers consisting of 2:1 (Ag(I):L). [Ag 2 (L)(CH 3 CN) 2 ](X) 2 (X À = ClO À 4 and BF À 4 ) and [Ag 2 (L)(H 2 O)](BF 4 ) 2 are double-stranded 1D, whereas [Ag 2 (ClO 4 ) 2 (L)(Me 2 CO) 2 ] yields a 2D network structure. The molecular construction has been affected by anions, solvents, and the crystallization method. The natures of anion-and solvent-coordination, including the argentophilic interaction play important roles in the formation of skeletal structures. For [Ag 2 (L)(CH 3 CN) 2 ](ClO 4 ) 2 , weakly coordinated solvate acetonitrile reversibly associates and dissociates in the solid state.
European Journal of Inorganic Chemistry, 2004
New Au I /Ag I complexes containing one or two substituted pyrazole ligands [Au(Hpz bp2)(PPh 3)](p-CH 3 C 6 H 4 SO 3) [Hpz bp2 = 3,5-bis(4-n-butoxyphenyl)pyrazole] (1) and [M(Hpz R2) 2 ] n X [Hpz R2 = Hpz bp2 , M = Au, n = 1, X = p-CH 3 C 6 H 4 SO 3 (2), NO 3 − (3); n = 2, X = 1,5-naphthalenedisulfonate (1,5nds) (4); Hpz R2 = Hpz bp2 , M = Ag, n = 1, X = BF 4 − (5), CF 3 SO 3 − (6); Hpz R2 = Hpz NO2 (3,5-dimethyl-4-nitropyrazole), M = Ag, n = 1, X = BF 4 − (7), CF 3 SO 3 − (8)], have been prepared and characterized. Compounds 1, 2, 5 and 8 have been proved to be useful for supramolecular assembly from their single X-ray diffraction analysis. In all cases strong
Zeitschrift für anorganische und allgemeine Chemie, 2019
New hybrid ligands are reported that combine two types of popular donor groups within a single linear scaffold, viz., a central pyrazolate bridge and two appended bis(N‐heterocyclic carbene) units; the ligand strands thus provide two potentially tridentate {NCC} compartments. The pyrazole/tetraimidazolium proligands, [H5L1](PF6)4 and [H5L2](PF6)4, were synthesized via multi‐step protocols, and the NH prototropy of [H5L1](PF6)4 was examined by variable temperature (VT) NMR spectroscopy, giving solvent dependent activation parameters (ΔH‡ = 27.6 kJ·mol–1, ΔS‡ = –125 J·mol–1·K–1 in [D3]MeCN; ΔH‡ = 40.4 kJ·mol–1, ΔS‡ = –86.9 J·mol–1·K–1 in [D6]DMSO) that are in the range typical for pyrazoles. Reaction of the proligands with Ag2O gave hexametallic complexes [Ag6(L1)2](PF6)4 and [Ag6(L2)2](PF6)4 that involve all six potential donor atoms of the ligands, viz. the four CNHC and two Npz donors, in metal coordination. X‐ray crystallography revealed a chair‐like central {Ag6} deck in both com...
Coordination polymers and isomerism; a study using silver(i) and a π-stacked ligand
Journal of the Chemical Society, Dalton Transactions, 2001
The ligand 2,5-bis(2-pyridylmethylsulfanylmethyl)pyrazine (L) was prepared by the base coupling of 2-(sulfanylmethyl)pyridine and 2,5bis(chloromethyl)pyrazine. This new ligand was treated with AgClO 4 in a 1:1 metal-to-ligand ratio and with AgNO 3 in a 1:2 metal-to-ligand ratio to give coordination polymers. The crystal structures of {[Ag(L)]ClO 4 } (1) and {[Ag 2 (L)](NO 3) 2 } (2) were determined. The Ag(I) ions in the onedimensional polymeric chains 1 adopted square-pyramidal geometries with the pyridine and pyrazine N donors coordinated in an extremely bent fashion. The structure of 2 revealed two isomeric polymer chains in the one crystal forming a single supramolecular array. The isomeric polymers differed in the donor atoms about the Ag(I) ions and in the arrangement of adjacent ligands along the chain. A feature of both structures was that L adopted a "three-layer" -stacked arrangement.
Acta crystallographica. Section E, Crystallographic communications, 2015
The asymmetric unit of the title compound, {[AgL]·BF4·0.5CH3OH} n , L = N-(pyridin-4-ylmeth-yl)pyridine-3-amine, C11H11N3, contains one Ag(I) ion, one ligand L, one tetra-fluorido-borate anion disordered over two orientations in a 0.669 (13):0.331 (13) ratio and one half of a methanol solvent mol-ecule situated on an inversion center. Each Ag(I) ion is coordinated by two N atoms from two L ligands in a distorted linear geometry [N-Ag-N = 174.70 (19)°]. Each L ligand bridges two Ag(I) ions, thus forming polymeric helical chains propagating in [010]. In the crystal, Ag⋯Ag [3.3369 (10) Å] and π-π inter-actions between the aromatic rings [centroid-to-centroid distance = 3.676 (4) Å] link these chains into layers parallel to (10-1). Ag⋯F and weak N(C)-H⋯F inter-actions further consolidate the crystal packing.
Crystal Growth & Design, 2005
The coordination chemistry of the oxadiazole-containing rigid bidentate ligands 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (L1) and 2,5bis(3-pyridyl)-1,3,4-oxadiazole (L2) with inorganic IIB metal salts have been investigated. Five new coordination polymers (1-5) were prepared by solution reactions and fully characterized by infrared spectroscopy, elemental analysis, and single-crystal X-ray diffraction. Cd(L1) 2 (CH 3 CN) 2 ](ClO 4 ) 2 AE (CH 3 CN) 2 (1) crystallized in the monoclinic space group P2 1 /c, a = 8.4028 Å , b = 21.3726(13) Å , c = 10.5617(7) Å , b = 95.1200(10)°, and Z = 2. In the solid state, it adopts an infinite two-dimensional polymeric structural motif with effective cross section of ca. 14.31 · 14.31 Å . Cd(L2)(H 2 O)(NO 3 ) 2 (2) crystallized in the monoclinic space group Ia, a = 7.1203(5) Å , b = 22.2475(15) Å , c = 20.2652(16) Å , b = 90.6080(10)°, and Z = 8. In the solid state, the two Cd(II) centers are connected to each other by L2 ligands and bridging nitrates into a two-dimensional network. [ZnCl 2 (L1)] (3) and [HgI 2 (L1)] AE CH 3 CN (4) crystallized in the monoclinic crystal system (3: P2 1 /c, a = 5.3702(3) Å , b = 20.4800(11) Å , c = 12.4093(7) Å , b = 94.7930(10)°, and Z = 4; 4: P2/n, a = 17.2733(11) Å , b = 5.2173(3) Å , c = 20.4069(13) Å , b = 102.8690(10)°, and Z = 4). In the solid state, Zn(II) and Hg(II) metal centers are connected to each other by L1 ligands into a zigzag chain motif. Compound 5 (HgBr 2 (L2) is different from 3 and 4, monoclinic, P2(1)/n, a = 5.470(4) Å , b = 16.271(13) Å , c = 16.486(12) Å , b = 93.197(15)°, and Z = 4) adopts a novel one-dimensional helical chain motif which resulted from the relative different coordinated orientation of the two N-donors on L2 ligand.
Inorganic Chemistry, 2008
New coordination polymers have been obtained by the self-assembly of silver salts AgX (X ) BF 4 , PF 6 , CF 3 SO 3 ) and 2,4-diamino-6-R-1,3,5-triazines L (R ) phenyl and p-tolyl) of formulas AgLX (1-6). A complex of different stoichiometry, [Ag 3 L 2 (H 2 O)(acetone) 2 ](BF 4 ) 3 , 7 (R ) phenyl), has also been synthesized. The three-dimensional structures of five compounds have been determined by X-ray diffraction studies. For the AgLX complexes, when X ) BF 4 and R ) phenyl or p-tolyl, chiral chains with alternating Ag and L are formed. The chains are cross-linked by the counteranions in a three-dimensional fashion through hydrogen bonds and weak Ag · · · F interactions giving rise to a structure with solvent-filled channels. Different and more compact structures have been found when the counteranion is CF 3 SO 3 (OTf). When R ) phenyl, sheets are formed which consist of [Ag 2 (OTf) 2 L 2 ] units with double triflate bridges and which contain columns of π-π stacked arenes. Hydrogen bonds connect the sheets. When AgOTf is used and R is p-tolyl, a different and unusual ladderlike structure is obtained in which the rungs are double asymmetric bridges consisting of the triflate groups bonded to Ag in κ 2 O,µ 2 -O and κ 1 O,µ 2 -O fashion. The ladders are parallel to each other and are mutually linked by N-H · · · N hydrogen bonds to give a 3D architecture. A very similar ladderlike structure has been found for 7 but with a water molecule and a BF 4group acting as bridges. The role played by the hydrogen bonds in complex 6 to form the 3-D structure is played in 7 by [Ag(acetone) 2 ] fragments. The noncovalent interactions play an important role in the different solid-state 3D structures. The behavior of the new derivatives in solution has also been analyzed. A new species has been detected at low temperatures, and this exhibits restricted rotation of the phenyl ring. Moler, D. B.; Li, H.; Chen, B.; Reineke, T. M.; O'Keeffe, M.; Yagi, O. M. Acc. Chem. Res. 2001, 34, 319-330. (d) Ockwig, N. W.; Delgado-Friedrichs, O.; O'Keeffe, M.; Yagi, O. M.
Silver(I)–3,6-bis(pyridin-3-yl)-1,2,4,5-tetrazine coordination polymers: a diversity of chain motifs
Crystal Engineering, 1999
The influence of solvent and anion on the formation of coordination polymers between silver(I) and 3,6-bis(pyridin-3-yl)-1,2,4,5-tetrazine (3,3Ј-pytz), a bridging ligand that can adopt both cisoid and transoidconformations, is reported. Reaction of AgPF 6 in MeCN with 3,3Ј-pytz in CH 2 Cl 2 gives ([{Ag(NCMe) 2 }(-3,3Ј-pytz)][PF 6 ]⅐MeCN) ϱ , 1, of AgPF 6 in MeNO 2 and 3,3Ј-pytz in CH 2 Cl 2 gives ([{Ag 2 (-3,3Ј-pytz) 2 }(-3,3Ј-pytz)][PF 6 ] 2 ⅐ 4MeNO 2 ) ϱ , 2, and of AgCF 3 SO 3 in MeCN and 3,3Ј-pytz in CH 2 Cl 2 gives {[Ag(-3,3Ј-pytz)]CF 3 SO 3 } ϱ , 3. These cationic coordination polymers exclusively form chain structural motifs. That in 1, ([{Ag(NCMe) 2 }(-3,3Јpytz)] ϩ ) ϱ , has a castellated construction with each tetrahedral silver(I) center coordinated by two solvent molecules as well as two linking transoid-oriented 3,3Ј-pytz bridges (Ag . . . Ag 13.210 Å) in a 1:1 polymeric chain. That in 2, ([{Ag 2 (-3,3Ј-pytz) 2 }(-3,3Ј-pytz)] 2ϩ ) ϱ , is novel. It is the first coordination polymer to exhibit both cisoid and transoid conformations of a bridging ligand coordinated to the same metal center. Pairs of silver(I) centers are linked by pairs of cisoid-oriented 3,3Ј-pytz molecules (Ag . . . Ag ϭ 11.695 Å) to form [Ag 2 (-3,3Ј-pytz) 2 ] motifs, which are bridged, in turn, by transoid-oriented 3,3Ј-pytz molecules (Ag . . . Ag ϭ 13.318 Å) to form a 3:2 ligand:metal infinite polymeric zigzag chain. That in 3, {[Ag(-3,3Ј-pytz)] ϩ } ϱ , has a zigzag architecture despite being based on linear silver(I) centers. Transoid-oriented 3,3Ј-pytz molecules link silver(I) centers (Ag . . . Ag 13.225 Å) to give a 1:1 ligand:metal infinite polymeric zigzag chain. The chains aggregate in parallel
Crystals, 2016
Two new linear silver(I) nitrate coordination polymers with bitopic ligand 1,1,2,2tetra(pyrazol-1-yl)ethane were synthesized. Synthesized compounds were characterized by IR spectroscopy, elemental analysis, powder X-ray diffraction and thermal analysis. Silver coordination polymers demonstrated a yellow emission near 500 nm upon excitation at 360 nm. Crystal structures of coordination polymers were determined and structural peculiarities are discussed. In both of the structures, silver ions are connected via bridging ligand molecules to form polymeric chains with a five-atomic environment. The coordination environment of the central atom corresponds to a distorted trigonal bipyramid with two N atoms of different ligands in apical positions. The Ag-N bond distances vary in a wide range of 2.31-2.62 Å, giving strongly distorted metallacycles. Thermolysis of coordination polymers in reductive atmosphere (H 2 /He) leads to the formation of silver nanoparticles with a narrow size distribution.