Synthesis and crystal structures of two 1H-benzo[d]imidazole derivatives: DFT and anticorrosion studies, and Hirshfeld surface analysis.

The title benzimidazole compounds, namely, 2-(4-methoxynaphthalen-1-yl)-1H-benzo[d]imidazole, C18H14N2O (I) and 2-(4-methoxynaphthalen-1-yl)-1-[(4-methoxynaphthalen-1-yl)methyl]-1H-benzo[d]imidazole ethanol monosolvate, C30H24N2O2·C2H6O (II), were synthesized by the condensation reaction of benzene-1,2-diamine with 4-methoxynaphthalene-1-carbaldehyde in the ratios 1:1 and 1:2, respectively. In I, the mean plane of the naphthalene ring system is inclined to that of the benzimidazole ring by 39.22 (8)°, while in II, the corresponding dihedral angle is 64.76 (6)°. This difference is probably influenced by the position of the second naphthalene ring system in II; it is inclined to the benzimidazole ring mean plane by 77.68 (6)°. The two naphthalene ring systems in II are inclined to one another by 75.58 (6)°. In the crystal of I, molecules are linked by N-H...N hydrogen bonds to form chains propagating along the a-axis direction. Inversion-related molecules are also linked by a C-H...π interaction linking the chains to form layers lying parallel to the ac plane. In the crystal of II, the disordered ethanol molecule is linked to the molecule of II by an O-H...N hydrogen bond. There are a number of C-H...π interactions present, both intra- and intermolecular. Molecules related by an inversion centre are linked by C-H...π interactions, forming a dimer. The dimers are linked by further C-H...π interactions, forming ribbons propagating along the b-axis direction. The interatomic contacts in the crystal structures of both compounds were explored using Hirshfeld surface analysis. The molecular structures of I and II were determined by density functional theory (DFT) calculations at the M062X/6-311+g(d) level of theory and compared with the experimentally determined molecular structures in the solid state. Local and global reactivity descriptors were computed to predict the reactivity of the title compounds. Both compounds were shown to exhibit significant anticorrosion properties with respect to iron and copper.

Crystal structure and Hirshfeld surface analysis of 1-[(E)-2-(3-nitro-phen-yl)diazen-1-yl]naphthalen-2-ol.

The title compound, C16H11N3O3, belongs to the family of azo dyes. In the light of a single-crystal X-ray study, it is evident that of the tautomeric forms (azo-hydrazone), the hydrazone form is the predominant form in the solid state, namely, (1E)-1-[2-(3-nitro-phen-yl)hydrazin-1-yl-idene]-1,2-di-hydro-naphthalen-2-one. The naphthol and benzene fragments attached to the -N=N- moiety adopt the s-trans conformation. Furthermore, the mol-ecules are nearly coplanar, subtending a dihedral angle of 2.63 (5)°. An intra-molecular N-H⋯O hydrogen bond occurs. There are only two types of inter-molecular inter-actions in the crystal structure: strong hydrogen-bonding C-H⋯O inter-actions and π-π stacking inter-actions. The importance of C-H⋯O inter-actions in the mol-ecular packing is reflected by the relatively high contributions (28.5%) made by O⋯H/H⋯O contacts to the Hirshfeld surface.

Bis(2-amino-3,5-di-chloro-pyridinium) hexa-chlorido-stannate(IV) dihydrate.

The title hybrid compound, (C5H5N2Cl2)2[SnCl6]·2H2O, was synthesized and its structure was identified by single-crystal X-ray diffraction. The structure is non-polymeric (0D) in terms of containing isolated [SnCl6]2- polyhedra. The special position (0,0,0) of the SnIV atom in the crystal structure gives rise to a stacking structure with alternating cationic and anionic layers parallel to (001). The water mol-ecules are inter-calated between these layers, which are linked by cation-anion hydrogen bonds and dominant non-covalent inter-actions. The stability of the three-dimensional network for this compound is also discussed.

4-Amidino-pyridinium hexa-chlorido-stannate(IV) dihydrate.

In the title hydrated mol-ecular salt {systematic name: 4-[amino-(iminium-yl)meth-yl]pyridin-1-ium hexa-chlorido-stannate(IV) dihydrate}, (C6H9N3)[SnCl6]·2H2O, the tin atom lies on a crystallographic inversion centre and the organic cation shows whole-mol-ecule disorder. Numerous N-H⋯O, N-H⋯Cl and O-H⋯Cl hydrogen bonds link the components in the crystal.

A new chiral rare-earth organic framework constructed by tartaric acid: synthesis, structural, thermal investigations and optical properties.

Hydrothermal reactions of rare-earth cerium with L-tartaric acid afford a new coordination polymer, namely, poly[[triaqua(µ4-L-tartrato)cerium(III)] chloride], {[Ce(C4H4O6)(H2O)3]Cl}n, (1). The structure was determined by single-crystal X-ray diffraction analysis and further characterized by IR and UV-Vis spectroscopy, powder X-ray diffraction and thermogravimetric analysis. Single-crystal X-ray diffraction analysis revealed that the compound is a new two-dimensional (2D) double-layered structure with one-dimensional left-handed helical chains. The different intermolecular interactions were confirmed using Hirshfeld surface analysis and molecular fingerprint plots. Molecular 2D fingerprint plots quantify the different interactions and highlight that H...H (24.8%), H...O/O...H (26.3%), Cl...H/H...Cl (19.6%), O...O (13.8%) and Ce...O/O...Ce (13.6%) interactions account for 99.8% of all contacts. Additionally, the photoluminescence properties of the compound were investigated in the solid state.

Alkali and alkaline earth coordination polymers constructed from benzene-1,2,4,5-tetracarboxylic acid and flexible dicarboxylate acid ligands: syntheses, structures and spectroscopic and thermal properties.

Two new metal coordination complexes, namely, poly[aqua(µ6-benzene-1,2,4,5-tetracarboxylic acid-κ8O1:O1,O2:O2':O4:O4,O5:O5')(µ-but-2-enedioato-κ2O1:O4)potassium(I)], [K2(C4H2O4)(C10H6O8)(H2O)2]n or [K2(fum)(H4btec)(H2O)2]n, (1), and poly[aqua(µ8-2,5-dicarboxybenzene-1,4-dicarboxylato-κ12O1:O1',O2:O2,O2':O2':O4:O4',O5:O5,O5':O5')(µ-ethanedioato-κ4O1,O2:O1',O2')strontium(II)], [Sr2(C2O4)(C10H4O8)(H2O)2]n or [Sr2(ox)(H2btec)(H2O)2]n, (2) (H4btec = benzene-1,2,4,5-tetracarboxylic acid, H2btec = 2,5-dicarboxybenzene-1,4-dicarboxylate, fum = fumarate and ox = oxalate), have been obtained under hydrothermal conditions by reacting the different alkali and alkaline earth metal salts with H4btec, fumaric acid (H2fum) and oxalic acid (H2ox). Complexes (1) and (2) were structurally characterized by single-crystal X-ray diffraction, IR and UV-Vis spectroscopy, powder X-ray diffraction (PXRD) and thermogravimetic analysis-differential scanning calorimetry (TGA-DSC). Complex (1) displays a two-dimensional (2D) layer with the K+ ion in a distorted pentagonal bipyramidal geometry and exhibits a uninodal 6-connected hxl/Shubnikov plane net (3,6) with {36.46.53} topology. Complex (2) displays a three-dimensional (3D) network structure, in which the Sr2+ ion is in a distorted monocapped square antiprism geometry. The framework possess a binodal (5,8)-connected net with the Schläfli symbol {32.410.58.64.74}{32.46.52}2. The 3D Hirshfeld surfaces and 2D fingerprint plots show that the main interactions are the O...H/H...O intermolecular interactions. Moreover, the thermal decompositions of (1) and (2) in the temperature range 303-1273 K revealed that they both decompose in three steps and transform to the corresponding metal oxide.

A new P,S-coordinating ferrocenyl ligand: synthesis of a precursor and its coordination compounds with PdII and PtII. Corrigendum.

In the paper by Mouas Toma et al. [Acta Cryst. (2014), C70, 460-464], there was an error in the name of the first author.

Erratum: rac-{[2-(Diphenyl-thio-phosphor-yl)ferrocen-yl]meth-yl}dimethyl-ammonium diphenyl-dithio-phosphinate. Corrigendum.

[This corrects the article DOI: 10.1107/S1600536812009129.].

Synthesis, crystal structure and Hirshfeld surface of bis-(2-amino-pyridinium) hexa-chlorido-stannate(IV).

In the title mol-ecular salt, (C5H7N2)2[SnCl6], the cation is protonated at the pyridine N atom and the complete dianion is generated by a crystallographic centre of symmetry. In the crystal, N-H⋯Cl hydrogen bonds link the components into a three-dimensional network built up from the stacking of alternate cationic and anionic layers. The nature of the inter-molecular inter-actions has been analysed in terms of the Hirshfeld surfaces of the cations and the anions. The thermal behaviour and the Raman spectrum of the title compound are reported.

In situ synthesis, crystal structures, topology and photoluminescent properties of poly[di-µ-aqua-di-aqua-[µ3-4-(1H-tetra-zol-1-id-5-yl)benzoato-κ4 O:O,O':O'']barium(II)] and poly[µ-aqua-di-aqua-[µ3-4-(1H-tetra-zol-1-id-5-yl)benzoato-κ4 O:O,O':O']strontium(II)].

Two alkaline-earth coordination compounds, [Ba(C8H4N4O2)(H2O)4] n , (I), and [Sr(C8H4N4O2)(H2O)3] n , (II), from the one-pot hydrolysis transformation of benzoyl chloride and the in situ self-assembled [2 + 3] cyclo-addition of nitrile are presented. These coordination compounds are prepared by reacting 4-cyano-benzoyl chloride with divalent alkaline-earth salts (BaCl2 and SrCl2) in aqueous solution under hydro-thermal conditions. The mononuclear coordination compounds (I) and (II) show the same mode of coordination of the organic ligands. The cohesion of the crystalline structures is provided by hydrogen bonds and π-stacking inter-actions, thus forming three-dimensional supra-molecular networks. The two compounds have a three-dimensional (3,6)-connected topology, and the structural differences between them is in the number of water mol-ecules around the alkaline earth metals. Having the same emission frequencies, the compounds exhibit photoluminescence properties with a downward absorption value from (I) to (II).

Crystal structure, characterization and Hirshfeld analysis of bis-{(E)-1-[(2,4,6-tri-bromo-phen-yl)diazen-yl]naphthalen-2-olato}copper(II) dimethyl sulfoxide monosolvate.

In the title compound, [Cu(C16H8Br3N2O)2]·C2H6OS, the CuII atom is tetra-coordinated in a square-planar coordination, being surrounded by two N atoms and two O atoms from two N,O-bidentate (E)-1-[(2,4,6-tri-bromo-phen-yl)diazen-yl]naphthalen-2-olate ligands. The two N atoms and two O atoms around the metal center are trans to each other, with an O-Cu-O bond angle of 177.90 (16)° and a N-Cu-N bond angle of 177.8 (2)°. The average distances between the CuII atom and the coordinated O and N atoms are 1.892 (4) and 1.976 (4) Å, respectively. In the crystal, complexes are linked by C-H⋯O hydrogen bonds and by π-π inter-actions involving adjacent naphthalene ring systems [centroid-centroid distance = 3.679 (4) Å]. The disordered DMSO mol-ecules inter-act weakly with the complex mol-ecules, being positioned in the voids left by the packing arrangement of the square-planar complexes. The DMSO solvent mol-ecule is disordered over two positions with occupancies of 0.70 and 0.30.

A strongly fluorescent NiII complex with 2-(2-hy-droxy-eth-yl)pyridine ligands: synthesis, characterization and theoretical analysis and comparison with a related polymeric CuII complex.

The synthesis and characterization of di-aqua-bis-[2-(2-hy-droxy-eth-yl)pyridine-κ2N,O)nickel(II) dinitrate, [Ni(C7H9NO)2(H2O)2](NO3)2, under ambient conditions is reported and compared with catena-poly[[bis-[2-(2-hy-droxy-eth-yl)pyridine-κ2N,O]copper(II)]-µ-sulfato-κ2O:O'], [Cu(C7H9NO)2(SO4)] n [Zegh-ouan et al. (2016 ▸). Private communication (refcode 1481676). CCDC, Cambridge, England]. In the two complexes, the 2-(2-hy-droxy-eth-yl)pyridine ligands coordinate the metal ions through the N atom of the pyridine ring and the O atom of the hy-droxy group, creating a chelate ring. The NiII or CuII ion lies on an inversion centre and exhibits a slightly distorted MO4N2 octa-hedral coordination geometry, build up by O and N atoms from two 2-(2-hy-droxy-eth-yl)pyridine ligands and two water mol-ecules or two O atoms belonging to sulfate anions. The sulfate anion bridges the CuII ions, forming a polymeric chain. The photoluminescence properties of these complexes have been studied on as-synthesized samples and reveal that both compounds display a strong blue-light emission with maxima around 497 nm. From DFT/TDDFT studies, the blue emission appears to be derived from the ligand-to-metal charge-transfer (LMCT) excited state. In addition, the IR spectroscopic properties and thermogravimetric behaviours of both complexes have been investigated.

Synthesis, X-ray structure, in silico calculation, and carbonic anhydrase inhibitory properties of benzylimidazole metal complexes.

Three coordination compounds of formula {M(bmim)2Cl2} were synthetised (M = Co, Zn, and Hg) and fully characterised. Each complex incorporates 1-benzyl-2-methylimidazole (bmim) as ligand. The coordination polyhedron around the metal center for all complexes has a quasi-regular tetragonal geometry. Density functional theory calculations were carried out on the title compounds and as well on hypothetical complexes (Cu, Ni), in order to elucidate their electronic and molecular structure. The calculations reproduced the Co, Zn, and Hg experimental structures and could predict stable complexes in the case of Ni(II) and Cu(II) ions. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory effects of the three complexes were investigated. Only compound {Hg(bmim)2Cl2} (3) exhibited a modest inhibitory effect against hCA I, probably due to the affinity of Hg(II) for His residues at the entrance of the active site cavity.

The crystal structure of a new ferrocenyl P,N ligand: 1-[(2,2-di-methyl-hydrazin-1-yl-idene)meth-yl]-1'-(di-phenyl-phospho-rothio-yl)ferrocene.

The asymmetric unit of the title compound, [Fe(C8H11N2)(C17H14PS)], contains two independent mol-ecules (A and B) with very similar conformations. Each mol-ecule is built up from a ferrocene unit substituted in the 1 and 1' positions by a protected sulfur di-phenyl-phosphine and by a di-methyl-hydrazine, -C(H)=N-N(CH3)2, fragment. The two independent mol-ecules are linked by a C-H⋯N hydrogen bond. In the crystal, the A-B dimer is linked by a pair of C-H⋯S hydrogen bonds, forming a centrosymmetric four-mol-ecule arrangement. These units are linked by C-H⋯π inter-actions, forming a supra-molecular three-dimensional structure.

Crystal structure, Hirshfeld surface analysis and anti-oxidant capacity of 2,2'-{(1E,1'E)-[1,2-phenyl-enebis(aza-nylyl-idene)]bis-(methanylyl-idene)}bis-(5-benz-yloxy)phenol.

The whole mol-ecule of the title Schiff base compound, C34H28N2O4, is generated by mirror symmetry, with the mirror bis-ecting the central benzene ring. It was synthesized via the condensation reaction of 1,2-di-amine-benzene with 4-benz-yloxy-2-hy-droxy-benzaldehyde. The mol-ecule is V-shaped and there are two intra-molecular O-H⋯N hydrogen bonds present forming S(6) ring motifs. The configuration about the C=N imine bonds is E. The central benzene ring makes dihedral angles of 41.9 (2) and 43.6 (2)° with the phenol ring and the outer benz-yloxy ring, respectively. The latter two rings are inclined to each other by 84.4 (2)°. In the crystal, mol-ecules are linked by C-H⋯π inter-actions, forming layers lying parallel to the ab plane. The Hirshfeld surface analysis and the two-dimensional fingerprint plots confirm the predominance of these inter-actions in the crystal structure. The anti-oxidant capacity of the compound was determined by the cupric reducing anti-oxidant capacity (CUPRAC) process.

(E)-2-{[(2-Amino-phen-yl)imino]-meth-yl}-5-(benz-yl-oxy)phenol and (Z)-3-benz-yl-oxy-6-{[(5-chloro-2-hy-droxy-phen-yl)amino]-methyl-idene}cyclo-hexa-2,4-dien-1-one.

The title Schiff base compounds, C20H18N2O2 (I) and C20H16ClNO3 (II), were synthesized from 4-benz-yloxy-2-hy-droxy-benzaldehyde by reaction with 1,2-di-amino-benzene for (I), and condensation with 2-amino-4-chloro-phenol for (II). Compound (I) adopts the enol-imine tautomeric form with an E configuration about the C=N imine bond. In contrast, the o-hy-droxy Schiff base (II), is in the keto-imine tautomeric form with a Z configuration about the CH-NH bond. Neither mol-ecule is planar. In (I), the central benzene ring makes dihedral angles of 46.80 (10) and 78.19 (10)° with the outer phenyl-amine and phenyl rings, respectively, while for (II), the corresponding angles are 5.11 (9) and 58.42 (11)°, respectively. The mol-ecular structures of both compounds are affected by the formation of intra-molecular contacts, an O-H⋯N hydrogen bond for (I) and an N-H⋯O hydrogen bond for (II); each contact generates an S(6) ring motif. In the crystal of (I), strong N-H⋯O hydrogen bonds form zigzag chains of mol-ecules along the b-axis direction. Mol-ecules are further linked by C-H⋯π inter-actions and offset π-π contacts and these combine to form a three-dimensional network. The density functional theory (DFT) optimized structure of compound (II), at the B3LYP/6-311+G(d) level, confirmed that the keto tautomeric form of the compound, as found in the structure determination, is the lowest energy form. The anti-oxidant capacities of both compounds were determined by the cupric reducing anti-oxidant capacity (CUPRAC) process.

Crystal structures and anti-oxidant capacity of (E)-5-benz-yloxy-2-{[(4-chloro-phen-yl)imino]-meth-yl}phenol and (E)-5-benz-yloxy-2-({[2-(1H-indol-3-yl)eth-yl]iminium-yl}meth-yl)phenolate.

The title Schiff base compounds, C20H16ClNO2 (I) and C24H22N2O2 (II), were synthesized via the condensation reaction of 2-amino-4-chloro-phenol for (I), and 2-(2,3-di-hydro-1H-indol-3-yl)ethan-1-amine for (II), with 4-benz-yloxy-2-hy-droxy-benzaldehyde. In both compounds, the configuration about the C=N imine bond is E. Neither mol-ecule is planar. In (I), the central benzene ring makes dihedral angles of 49.91 (12) and 53.52 (11)° with the outer phenyl and chloro-phenyl rings, respectively. In (II), the central benzene ring makes dihedral angles of 89.59 (9) and 72.27 (7)°, respectively, with the outer phenyl ring and the mean plane of the indole ring system (r.m.s. deviation = 0.011 Å). In both compounds there is an intra-molecular hydrogen bond forming an S(6) ring motif; an O-H⋯O hydrogen bond in (I), but a charge-assisted N+-H⋯O- hydrogen bond in (II). In the crystal of (I), mol-ecules are linked by C-H⋯π inter-actions, forming slabs parallel to plane (001). In the crystal of (II), mol-ecules are linked by pairs of N-H⋯O hydrogen bonds, forming inversion dimers. The dimers are linked by C-H⋯O hydrogen bonds, C-H⋯π inter-actions and a weak N-H⋯π inter-action, forming columns propagating along the a-axis direction. The anti-oxidant capacity of the synthesized compounds was determined by cupric reducing anti-oxidant capacity (CUPRAC) for compound (I) and by 2,2-picrylhydrazyl hydrate (DPPH) for compound (II).

Synthesis, structure characterization, photoluminescence properties and TD-DFT calculations for two new borates.

Due to their rich structural chemistry and wide variety of applications, borate materials have provided a rich area of research. In a continuation of this research, diethylammonium bis(2-oxidobenzoato-κ2O1,O2)borate, C4H12N+·BO4(C7H4O)2-, (1), and propylammonium bis(2-oxidobenzoato-κ2O1,O2)borate, C3H10N+·BO4(C7H4O)2-, (2), have been synthesized by the reaction of boric acid with salicylic acid under ambient conditions. In both structures, the B atom exhibits a slightly distorted tetrahedral environment formed by the bidentate coordination of two salicylate anions via the O atoms of the central carboxylate and oxide groups. In the crystals of salts (1) and (2), mixed cation-anion layers lying parallel to the (101) plane are formed through N-H...O, C-H...O and C-H...π/N-H...O hydrogen-bonding interactions, resulting, in each case, in a two-dimensional supramolecular architecture in the solid state. The photoluminescence properties of the salts were studied using the as-synthesized samples and reveal that salts (1) and (2) both display a strong blue-light emission, with maxima at 489 and 491 nm, respectively. In DFT/TD-DFT (time-dependent density functional theory) studies, the blue emission appears to be derived from an intramolecular charge transfer (ICT) excited state. In addition, IR and UV-Vis spectroscopies were used to investigate the title salts.

Two novel alkaline earth coordination polymers constructed from cinnamic acid and 1,10-phenanthroline: synthesis and structural and thermal properties.

In coordination chemistry and crystal engineering, many factors influence the construction of coordination polymers and the final frameworks depend greatly on the organic ligands used. The diverse coordination modes of N-donor ligands have been employed to assemble metal-organic frameworks. Carboxylic acid ligands can deprotonate completely or partially when bonding to metal ions and can also act as donors or acceptors of hydrogen bonds; they are thus good candidates for the construction of supramolecular architectures. We synthesized under reflux or hydrothermal conditions two new alkaline earth(II) complexes, namely poly[(1,10-phenanthroline-κ2N,N')bis(µ-3-phenylprop-2-enoato-κ3O,O':O)calcium(II)], [Ca(C10H7O2)2(C10H8N2)]n, (1), and poly[(1,10-phenanthroline-κ2N,N')(µ3-3-phenylprop-2-enoato-κ4O:O,O':O')(µ-3-phenylprop-2-enoato-κ3O,O':O)barium(II)], [Ba(C10H7O2)2(C10H8N2)]n, (2), and characterized them by FT-IR and UV-Vis spectroscopies, thermogravimetric analysis (TGA) and single-crystal X-ray diffraction analysis, as well as by powder X-ray diffraction (PXRD) analysis. Complex (1) features a chain topology of type 2,4 C4, where the Ca atoms are connected by O and N atoms, forming a distorted bicapped trigonal prismatic geometry. Complex (2) displays chains of topology type 2,3,5 C4, where the Ba atom is nine-coordinated by seven O atoms of bridging/chelating carboxylate groups from two cinnamate ligands and by two N atoms from one phenanthroline ligand, forming a distorted tricapped prismatic arrangement. Weak C-H...O hydrogen bonds and π-π stacking interactions between phenanthroline ligands are responsible to the formation of a supramolecular three-dimensional network. The thermal decompositions of (1) and (2) in the temperature range 297-1173 K revealed that they both decompose in three steps and transform to the corresponding metal oxide.

Crystal structure, thermal and fluorescence properties of 2,2':6',2''-terpyridine-1,1',1''-triium tetra-chlorido-nickelate(II) chloride.

The title compound, (C15H14N3)[NiCl4]Cl, comprises an NiII cation tetra-hedrally coordinated by four chloride anions, a non-coordinating chloride anion and an essentially planar terpyridinium trication (tpyH33+), in which the central pyridinium ring forms dihedral angles of 5.7 (2) and 6.0 (2)° with the peripheral pyridinium rings. Three inter-species N-H⋯Cl hydrogen bonds are formed with the Cl- anion, which also forms a link between the (tpyH33+) cations through an aromatic C-H⋯Cl inter-action, forming a zigzag chain extending along the 21 (b) screw axis. Two of the anionic Cl atoms of the [NiCl4]2- anions form Ni-Cl⋯π inter-actions with separate pyridinium rings [Ni⋯Cg = 3.669 (3) and 3.916 (4) Å]. In the crystal, successive undulating inorganic and organic layers are formed, extending across the (100) plane. Thermogravimetric and differential thermal analysis (TGA/DTA) indicate that the compound starts to decompose at 313 K and may be a candidate for use as a blue-light luminescent material.