Crystal chemical analysis of structures of the unsaturated tetraazamacrocyclic gold(III) complexes

The detailed comparative study is carried out for crystal structure packings of the following gold(III) complexes with unsaturated ligands: [Au(C₁₄H₂₂N₄)]Br (I), [Au(C₁₄H₂₃N₄)](ClO₄)₂ (II), [Au(C₁₄H₂₄N₄)](H₃O)(ClO₄)₄ (III). The determining role in the topological pattern of packings I–III belongs to the compositions and structures of the cations along with the ability of the ions of the complexes to act as donors and acceptors of hydrogen bonds. The 3D packings of complexes I and II containing iminate six-membered rings are determined and stabilized by a wide network of weak hydrogen bonds (C–H…π, C–H…Au, and C–H…Br(O)) and short contacts Au(N)…O (in structure II). The structure of imine complex III is characterized by one-dimensional piles formed due to hydrogen bonds O(w)–H…O and contacts Au…O of the О(2) atom of anion Сl(1)О ₄ ^- with cations (H₃O)⁺ and [Au(C₁₄H₂₄N₄)]³⁺ (CIF files CCDC 251258 (I), 276132 (II), and 287784 (III)).     

Synthesis and crystal structures of two new Schiff base cobalt(II) and nickel(II) complexes

The Schiff base ligand (HL) obtained from phenylmethanamine and 5-methoxysalicylaldehyde are used as ligands for Co(II) and Ni(II) resulting in complexes [Co(L)₂] (I) and [Ni(L)₂] (II), and their solid state structures were determined by X-ray crystallography. In both complexes, weak interactions play an important role in the molecular self-assembly. Complex I was stacked up to the 2D layers by C-H…O hydrogen bonds and C-H…π interactions. In contrast, complex II was extended into 2D sheet by C-H…O hydrogen bonds, the C-H…π interactions, and edge-to-face interactions.     

Anions-induced assembly: Structures and luminescent properties

Self-assembly of a multidentate ligand containing pyridyl groups, namely, 6-phenyl-4-(4′-[2-(2-naphthalene)ethenyl]phenyl)-2,2′-bipyridine (L) with corresponding zinc(II) salts, affords a series of coordination complexes, ZnLI₂ (I), [ZnLCl₂]₂ · 2CH₂Cl₂ (II), ZnLBr₂ (III). Complexes I and II were characterized by single crystal X-ray diffraction (CIF files CCDC nos. 943273 (I), 944798 (II)). In complex I, the π-π stacking and C-H?π interactions based on the pyridyl group constructed the 1D and 2D structures. While in complex II, various weak interactions including hydrogen bonds (C-H?Cl and C-H?π) played significant roles in the final supramolecular structures. The luminescent properties of ligand and the complexes were investigated. The results reveal that different anions have shown a great influence on both the molecular structures and luminescent properties of the complexes.     

Synthesis and structure of tri-m-tolylbismuth dicarboxylates

Tri-m-tolylbismuth bis(2-methoxybenzoate) (I) (84%), tri-m-tolylbismuth dibenzoate (II) (91%), and tri-m-tolylbismuth bis(trichloroacetate) (III) (92%) have been synthesized via the reaction between tri-m-tolylbismuth, carboxylic acid, and hydrogen peroxide. According to X-ray diffraction data, a bismuth atom in compounds I–III have a distorted trigonal bipyramidal coordination (disregarding the additional coordination of carbonyl oxygen atoms) to m-tolyl ligands in equatorial positions. The Bi-C bonds in compounds I, II, and III range within 2.193(3)–2.228(5) Å, and the Bi-O and Bi…O(=C) distances are 2.267(3), 2.282(3) Å and 2.791(6), 2.895(6) Å in I; 2.293(2), 2.296(3) Å and 2.815, 2.905(5) Å in II; and 2.278(4), 2.300(4) Å and 3.008(9), 3.115(9) Å in III. The equatorial CBiC angles on the side of Bi…O(=C) contacts are considerably enlarged, thus decreasing the other two angles (150.6°, 104.7°, and 104.7° in I, 140.2°, 107.4°, and 112.3° in II, and 138.0°, 110.1°, and 111.0° in III).     

The syntheses and structures of two silver compounds based on Phdat

Based on the organic ligand 2,4-diamine-6-phenyl-1,3,5-triazine (Phdat), two Ag(I) compounds, Ag(Phdat)₂(NO₃) (I) and Ag(Phdat)₂(OAc) (II), have been synthesized and characterized by single crystal X-ray diffractions, elemental analyses, and IR spectra. Compounds I and II are mononuclear and binuclear structures, respectively, and with the help of N-H…O and N-H…N hydrogen bonds and π…π packing interactions, the 3D supramolecular networks are built up.     

Heterometallic complexes of macrocyclic oxamide with polycarboxylates: Syntheses,crystal structures,and magnetic properties

Three complexes with the formula [Co(Ip)(CuL)(H₂O)₂] · H₂O (I), [Co(Ip)(NiL)(H₂O)₂] · H₂O (II), [Co(CuL)₂(Hbtc)(H₂O)] (III), (H₂Ip = m-isophthalic acid; H₂L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien; H₃Btc = 1,3,5-benzenetricarboxylic acid) were synthesized and structurally characterized by elemental analysis, IR and UV spectroscopy. Single-crystal X-ray analyses reveal that the complexes I and II contain neutral heterometallic binuclear CoM (for I and II, M = Cu, Ni, respectively) moieties, and complex III contains discrete neutral trinuclear CoCu₂ moieties. The structures of I–III consist of two-dimensional supramolecular architecture formed by strong O-H…O intermolecular hydrogen bonds. Furthermore, the magnetic properties of complex I were investigated and discussed in detail.     

Synthesis and structural features of tris(5-bromo-2-methoxyphenyl)antimony dicarboxylates

Tris(5-bromo-2-methoxyphenyl)antimony bis(4-nitrophenylacetate) (I), tris(5-bromo-2-methoxyphenyl)antimony bis(2-methoxybenzoate) (II), and tris(5-bromo-2-methoxyphenyl)antimony bis(phenylpropiolate) (III) have been synthesized via the reaction between tris(5-bromo-2-methoxyphenyl) antimony and 4-nitrophenylacetic acid, 2-methoxybenzoic acid, and phenylpropiolic acid, respectively, in the presence of hydrogen peroxide (molar ratio: 1: 2: 1). According to X-ray diffraction data, the antimony atom in molecules of complexes I–III has a distorted trigonal bipyramidal coordination. The OSbO axial angles and the CSbC bond angles in the equatorial plane are 173.27(15)°, 172.96(11)°, 172.99(10)°, and 115.5(2)°–123.3(2)°, 108.81(16)°–129.32(17)°, and 110.66(17)°–127.91(17)°, respectively. The Sb-O bond lengths are 2.092(4) and 2.115(4)Å in I, 2.088(3) and 2.097(2) Å in II, and 2.096(3) and 2.120(3) Å in III. The Sb-C bonds range within 2.095(6)–2.123(6) Å in I, 2.107(4)–2.117(4) Å in II, and 2.097(4)–2.116(4) Å in III. Complexes I, II, and III are observed to have intramolecular Sb…OCH₃ contacts (3.169–3.226, 3.134–3.174, and 3.147–3.196 Å, respectively) in addition to Sb…O=C interactions (3.121, 3.139Å; 2.944, 3.038 A0; 3.111, 3.120 Å).     

Hydrothermal synthesis, crystal structure, and luminescence of a novel tetranuclear zinc(ii) complex

A new tetranuclear zinc(II) complex [Zn₄(tmphen)₄(tbip)₄(H₂O)₄] (1, tmphen = 3,4,7,8-tetramethyl-1,10-phenanthroline, H₂tbip = 5-tert-butyl isophthalic acid) is hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction, elemental analysis, and IR spectroscopy. In complex 1, four tbip^2? ligands act as bridges between four neighboring Zn atoms to form an unusual tetranuclear zinc cluster. The clusters are further connected by two types of O-H…O and C-H…O hydrogen bonds, generating a three-dimensional supramolecular structure. Meanwhile, π-π stacking interactions and C-H…π interactions further consolidate the three-dimensional supramolecular framework of 1. In addition, the luminescence measurements reveal that complex 1 exhibits strong fluorescent emissions in the solid state at room temperature.     

Synthesis and structural characterization of binuclear ytterbium(III) complexes with 2-amino and 3-amino benzoic acid

Two novel homobinuclear ytterbium(III) complexes, [Yb₂(2AMB)₆(H₂O)₄] · 2C₂H₆O (I) and Yb₂(3AMB)₆(H₂O)₄] · 3H₂O (II) (2AMB = 2-aminobenzoic acid, 3AMB = 3-aminobenzoic acid) have been synthesized and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis and X-ray crystallography (CIF files CCDC nos. 950103 (I), 921652 (II)). Complex I crystallizes in triclinic space group \(P\bar 1\) and complex II crystallizes in monoclinic space group P2₁/n. X-ray analysis shows that both complexes (I, II) have the dinuclear structure. The central Yb³⁺ ions in both complexes are eight-coordinated adopting distorted YbO₈ dodecahedral geometry. Each Yb³⁺ ion is coordinated to two O atoms from bridging carboxylate, four O atoms from the chelating carboxylate ligands and two O atoms of water molecules. The crystal structure of I and II are stabilized by N-H…O, O-H…O, O-H…N, and C-H…O hydrogen bonds, C-H…π interactions and weak π-π stacking interactions.     

Secondary interactions in the crystal structure of the iminate amine gold(III) complex [Au(C9H19N4)]I2

The acyclic iminate amine gold(III) complex iodide [Au(C₉H₁₉N₄)]I₂ (I) was obtained. The crystal structure of complex I is stabilized by weak secondary interactions N-H??I, C-H??Y (Y = I, Au, and ??), and Au??I forming an infinite 2D network. Double stacks of cations along the axis x are united through zigzag chains of H-bonds and of secondary contacts. Structure I contains 3?C14-membered cation-cation and cation-anion rings. The anions I(1)^? and I(2)^? act as bridges in structure I.     

Crystal structures of two 4-phenylbenzophenones

Two 4-phenylbenzophenones (I) and (II) are synthesized via Friedel-Crafts reactions. There are four crystallographically independent molecules with different conformations in the crystal structure of [1,1′-biphenyl]-4-yl(2-chlorophenyl)methanone (I). Crystals are orthorhombic, Pca2₁, C₁₉H₁₃ClO, a = 13.699(3) Å, b = 8.9385(17) Å, c = 46.836(9) Å; V = 5735(2) ų, Z = 16, d _x = 1.356 g/cm³. Torsion angles between the biphenyl rings are between 28.5° and 30.8°. Several C-H…O and C-H…Cl hydrogen bonds and weak π-π stacking contacts consolidate the crystal. Crystals of [1,1′-biphenyl]-4-yl(3-methoxyphenyl)methanone (II) are orthorhombic, Pbca, C₂₀H₁₆O₂, a = 7.8179(15) Å, b = 16.003(3) Å, c = 23.345(5) Å; V = 2920.7(10) ų, Z = 8, d _x = 1.311 g/cm³. The torsion angle between the biphenyl rings is 28.1° and C-H…O hydrogen bonds are observed in compound (II).     

Binding forms of gold(III) from solutions by cadmium diethyl dithiocarbamate: Thermal behavior and role of secondary interactions in the supramolecular self-assembly of polymeric complexes ([Au{S2CN(C2H5)2}2][AuCl4]) n and [Au{S2CN(C2H5)2}Cl2] n

The chemisorption interaction between the binuclear cadmium diethyl dithiocarbamate (EDtc), [Cd₂{S₂CN(C₂H₅)₂}₄], (chemisorbent I) and AuCl₃ solutions in 2 M HCl results in the formation of polymeric gold(III) complexes: ([Au{S₂CN(C₂H₅)₂}₂][AuCl₄]) _n (II) and [Au{S₂CN(C₂H₅)₂}Cl₂] _n (III) with the same Au : EDtc : Cl ratio (1 : 1 : 2). The alternating centrosymmetric cations and anions of complex II are structurally self-assembled to form linear polymeric chains: the gold atom in [Au{S₂CN(C₂H₅)₂}₂]⁺ forms secondary Au(1)?Cl(1) bonds (3.7784 Å) with two neighboring [AuCl₄]^? anions. This binding is additionally strengthened by secondary S(1)?Cl(1) interactions (3.4993 Å). The mixed-ligand complex III comprises two structurally non-equivalent molecules [Au{S₂CN(C₂H₅)₂}Cl₂]: A—Au(1) and B—Au(2), each being in contact with two nearest neighbors through pairs of unsymmetrical secondary bonds: Au(1)?S(1)^a/b 3.4361/3.6329; and Au(2)?S(4)^c/d 3.4340/3.6398 Å. At the supramolecular level, this gives rise to independent zigzag-like polymeric chains, (?A?A?A?) _n and (?B?B?B?) _n along which antiparallel isomeric molecules of III alternate. The chemisorption capacity of cadmium diethyl dithiocarbamate calculated from the gold(III) binding reaction is 963.2 mg of gold per 1 g of the sorbent. The recovery conditions for the bound gold were elucidated by simultaneous thermal analysis of II and III. The DSC curves reflect different sets of heat effects, because thermolysis occurs for complex molecules (III) or for cations and anions (II). Nevertheless, the patterns of experimental TG curves are similar despite different structures of the complexes. The final product of thermal transformations is reduced gold.     

Dichlorotriethylphosphine-[N-formyl-N,N′-bis(3,4-dimethoxy)benzyl-trimethylenediamine] platinum(II)

By treatment of 1,3-bis(3,4-dimethoxybenzyl)-3,4,5,6-tetrahydropyrimidinium chloride (1) with KOBu ^t and [PtCl₂(PEt₃)₂]₂ N-coordinated platinum complex (2) is obtained. The Pt atom is coordinated in square planar arrangements by two chloride ions in a trans-configuration, the N-formyl-N,N′-bisaryltrimethylenediamine nitrogen atom, and the phosphine P atom. An extensive three-dimensional network of three C-H…O hydrogen bonds, two C-H…π and one π…π interactions are responsible for the crystal stabilization. Intermolecular hydrogen bonds and C-H…π interactions produce R ₂ ² (6), R ₂ ² (22), R ₂ ² (24), R ₃ ³ (23), R ₄ ⁴ (26), and R ₄ ⁴ (32) rings.     

Three one-dimensional chains with bulky backbone carboxylate ligands: Syntheses,crystal structures,and luminescent properties

To explore the influence of bulky backbone on complexes, three Co(II) and Zn(II) complexes with phenanthrene-9-carboxylate (L¹), 9H-fluorene-9-carboxylate (L²) or biphenyl-4-carboxylate (L³) together with incorporating auxiliary bridging ligad 4,4′-bipyridine (4Bipy), were synthesized and characterized: [Co(L¹)₂(4Bipy)(H₂O)₂]_∞ (I), [Zn(L²)₂(4Bipy)_0.5(4Bipy)_0.5]_∞ (II), and [Zn₃(L³)₄(4Bipy)_0.5(4Bipy)_0.5(4Bipy)_0.5(OH)₂]_∞ (III). X-ray single-crystal diffraction analyses show that complexes I–III both assume one-dimensional (1D) structures by incorporating the bridging 4Bipy (CIF file CCDC nos. 942729 (I), 942727 (II), and 942733 III). In I, mononuclear six-coordinated Co²⁺ ions are linked into a 1D linear chain by 4Bipy. While in II, mononuclear four-coordinated Zn²⁺ ions are linked into a 1D zigzag chain by 4Bipy. But in III, because of the existence of OH^?, hexanuclear Zn(II) can be regarded as a node, then bridge adjacent hexanuclear Zn(II) nodes by almost parallelled three 4Bipy ligands into a 1D linear chain. Finally the 1D chains of I–III are further assembled into an overall three-dimensional (3D) framework via intermolecular H-bonding, π…π stacking, and/or C-H…π supramolecular interactions, respectively. The results indicate that, besides different metal ions Co²⁺ and Zn²⁺ or OH^? anions, the steric hindrance of backbone ligands play an important role in the formation of I–III. Moreover, the luminescent properties of corresponding ligands and their complexes were briefly investigated.     

Oxidative addition reactions of tri(2-methylphenyl)antimony

Bis[??-oxo-tri(2-methylphenyl)antimony] (I) was synthesized via oxidation of tri(2-methylphenyl)antimony by hydrogen peroxide in ether. In the presence of 2-hydroxy-5-bromobenzaldoxime or furfural oxime, the reaction between these reactants (in a 1: 1: 1 molar ratio, respectively) yields (??-oxo)bis[2-hydroxy-5-bromobenzaldoximato-tri(2-methylphenyl)antimony] (II) or (??-oxo)bis[furfural-oximatotri(2-methylphenyl)antimony] (III). The structures of compounds I?CIII was determined by X-ray diffraction. In the centrosymmetric dimeric complex I, the Sb atom has a distorted trigonal-bipyramidal coordination with oxygen atoms in equatorial and axial positions. In II and III, the axial positions are occupied by the bridge oxygen atom and the oxygen atom of the oxime ligand. Bond length values are as follows: Sb-C 2.137(3)?C2.183(3), 2.116(7)?C2.131(7), and 2.105(5)?C2.126(6)?; Sb-O 1.934(2), 2.077(2), 1.973(4)?C2.151(4), and 1.9706(3)?C2.112(6) ? for I, II, and III, respectively. Intramolecular contacts Sb...N (2.953(8), 3.002(9), and 2.951(8) II and III.     

Copper(II) and cobalt(II) complexes with a chiral 5-pyrazolone derivative obtained from the terpene (+)-3-carene: Synthesis and properties

The complexes [CuLCl₂] (I), [CoLCl₂] (II), and CuLBr₂ (III) (where L is the derivative of optically active 5-pyrazolone prepared from the terpene (+)-3-carene) were obtained and characterized. According to X-ray diffraction data, crystal structures I and II (orthorhombic crystal system) are built from mononuclear acentric molecules. In the resulting complexes, the Cu²⁺ or Co²⁺ ion coordinates two N atoms of the chelating bidentate ligand L and two Cl atoms, thus making a distorted tetrahedron. Intermolecular contacts and the hydrogen bonds Cl(1)…H-O(1) give rise to columns parallel to axis y. For complexes I and III, μ_eff = 1.83 and 1.81 μB, respectively; these values correspond to the electronic configuration d ⁹ . For complex II, μ_eff = 4.42 μB, which suggests the tetrahedral structure of the coordination entity CoCl₂N₂. Complexes I and III were studied by EPR spectroscopy.     

Copper(I) halide complexes with N,N′-diallyl-N,N,N′,N′-tetramethylethylenediaminium (L2+). Synthesis and crystal structures of the complexes [L0.5CuCl2], [L0.5CuCl0.72Br1.28], and [L0.5CuBr2]

The Eschweiler-Clarke reaction of ethylenediamine with formaldehyde and formic acid yielded N,N,N′,N′-tetramethylethylenediamine, which was alkylated with allyl chloride or allyl bromide to give the corresponding N,N′-diallyl-N,N,N′,N′-tetramethylethylenediaminium (L²⁺) dihalides. In methanolic solutions of copper(II) halide and an appropriate ligand, ac electrochemical synthesis with copper wire electrodes afforded single crystals of Cu(I) complexes with L²⁺: [L_0.5CuCl₂] (I), [L_0.5CuCl_0.72Br_1.28] (II), and [L_0.5CuBr₂] (III). The crystal structures of complexes I–III were determined by X-ray diffraction study. The isostructural crystals of I and II are monoclinic, space group P2₁/n, Z = 4. For I: a = 7.632(4) Å, b = 11.318(5) Å, c = 10.635(5) Å, β = 98.551(7)°, V = 908.4(7) ų. For II: a = 7.7415(7) Å, b = 11.4652(9) Å, c = 10.7267(10) Å, β = 98.351(4)°, V = 942.0(2) ų. The organic cation L²⁺ acts as a bridge linking a pair of separate cuprous halide fragments Cu₂X₄. Although being isostoichiometric with I and II, complex III has a different structure. The crystals of III are monoclinic, space group P2₁/c, a = 6.519(2) Å, b = 9.060(3) Å, c = 16.284(6) Å, β = 97.219(4)°, V = 954.2(6) ų, Z = 4. In structure III, the inorganic fragment forms infinite polymer chains (CuBr ₂ ^? ) _n . The organic and inorganic parts are held together only by electrostatic interactions. Structures I–III are stabilized by hydrogen bonds (C)H…X (2.6–2.9 Å).     

X-ray diffraction investigation of siloxanes. I. Effects of organic substituents at the silicon atoms on the structure of acyclic trisiloxane-1,5-diols and on formation of different hydrogen bond systems

The molecular and crystal structure of four acyclic trisiloxane compounds, which differ in substituents at the silicon atoms (Ph-phenyl, mPh-methoxyphenyl, 2mPh-dimethoxyphenyl), was investigated by X-ray diffraction analysis. Due to intermolecular hydrogen bonding between the oxygen atoms of the diol fragments, the crystal structure of 1,1,5,5-tetramethyl-3,3-diphenyl-1,3,5-trisiloxane-1,5-diol (C₁₆H₂₄O₄Si₃) (I) is a double chain architecture with hydrogen-bonded dimeric motifs of C(8)R ₄ ⁴ (12) type in graph set representation. In 1,1,5,5-tetramethyl-3,3-(2-methoxybenzo)-1,3,5-trisiloxane-1,5-diol (C₁₈H₂₈O₆Si₃) (II) and 1,1,5,5-tetramethyl-3,3-(2,6-dimethoxybenzo)-1,3,5-trisiloxane-1,5-diol (C₂₀H₃₂O₈Si₃) (III), a double chain structure with a graph set R ₃ ³ (8)D ₃ ³ (10) is formed. In contrast to I–III, 1,1,3,3,5,5-hexaphenyl-1,3,5-trisiloxane-1,5-diol (C₃₆H₃₂O₄Si₃) (IV) has an intramolecular hydrogen bond S(8). The independent molecules are joined by O-H...O intermolecular hydrogen bonds into centrosymmetrical dimers; the system of hydrogen bonds in general may be described as S(8)R ₄ ⁴ (8).     

Catalase activity of cobalt(II) complexes with N,N,N′,N′-tetrasubstituted thiocarbamoylsulfenamides

On the base of the kinetic and activation parameters of the hydrogen peroxide decomposition in the presence of chelates of CoX₂ salts (X = Cl, Br, I, NCS) with N,N,N′,N′-tetrasubstituted thiocarbamoylsulfenamides containing exocyclic (out-of-chelate) fragments of dimethylamine (I), piperidine (II), and piperazine (III) the nature of acido-ligands influence on catalase activity of complexes I–III was revealed, depending on the structure and composition of the chelating ligand. Mononuclear complexes I(Br) and II(Br) can transform into 10-membered binuclear macrochelate intermediates.     

Synthesis and structure of bis(monohaloacetates) of tris(5-bromo-2-methoxyphenyl)antimony

Tris(5-bromo-2-methoxyphenyl)antimony bis(monohaloacetates) [(5-Br)(2-MeO)C₆H₃]₃Sb[OC(O)CH₂X]₂, X = Cl (I), Br (II), I (III) have been synthesized by the reaction of tris(5-bromo-2-methoxyphenyl)antimony with chloro-, bromo-, and iodoacetic acids in the presence of hydrogen peroxide. According to X-ray analysis the antimony atom in I–III has a distorted trigonal-bipyramidal coordination.