Synthesis, crystal structure and Hirshfeld surface analysis of bromido-tetra-kis-[5-(prop-2-en-1-yl-sulf-an-yl)-1,3,4-thia-diazol-2-amine-κN3]copper(II) bromide.

A novel cationic complex, bromido-tetra-kis-[5-(prop-2-en-1-ylsulfan-yl)-1,3,4-thia-diazol-2-amine-κN 3]copper(II) bromide, [CuBr](C5H7N3S2)4Br, was synthesized. The complex crystallizes with fourfold mol-ecular symmetry in the tetra-gonal space group P4/n. The CuII atom exhibits a square-pyramidal coord-ination geometry. The Cu atom is located centrally within the complex, being coordinated by four nitro-gen atoms from four AAT mol-ecules, while a bromine anion is located at the apex of the pyramid. The amino H atoms of AAT inter-act with bromine from the inner and outer spheres, forming a two-dimensional network in the [100] and [010] directions. Hirshfeld surface analysis reveals that 33.7% of the inter-mol-ecular inter-actions are from H⋯H contacts, 21.2% are from S⋯H/H⋯S contacts, 13.4% are from S⋯S contacts and 11.0% are from C⋯H/H⋯C, while other contributions are from Br⋯H/H⋯Br and N⋯H/H⋯N contacts.

2-Amino-benzoxazole-oxalic acid (2/1).

In the title compound, 2C7H7N2O+·C2O4 2-, proton transfer from oxalic acid to the N atom of the heterocycle has occurred to form a 2:1 molecular salt. In the extended structure, N-H⋯O hydrogen bonds link the components into [100] chains, which feature R 2 2(8) and R 4 4(14) loops.

Synthesis and structure of trans-bis-(4-amino-3-nitro-benzoato-κO)bis-(4-amino-3-nitro-benzoic acid-κO)di-aqua-manganese(II) dihydrate.

The manganese title complex, [Mn(C7H5N2O4)2(C7H6N2O4)2(H2O)2]·2H2O, is one of the first 4-amino 3-nitro-benzoic acid (4 A3NBA) monoligand metal complexes to be synthesized. It crystallizes in the centrosymmetric monoclinic space group P21/n with the complex mol-ecules located on inversion centers. Four 4 A3NBA ligand mol-ecules are monodentately coordinated by the Mn2+ ion through the carb-oxy-lic oxygen atoms while the other two positions of the inner coordination sphere are occupied by water mol-ecules, giving rise to a distorted octa-hedron, and two water mol-ecules are in the outer coordination sphere. There are two intra-molecular hydrogen bonds in the complex mol-ecule. The first is of the common N-H⋯O=N type, while the second is a rarely occurring very strong hydrogen bond in which a common proton is shared by two uncoordinated oxygen atoms of neighboring carboxyl-ate groups. In the crystal, an intricate system of inter-molecular hydrogen bonds links the complex mol-ecules into a three-dimensional-network.

Synthesis, crystal structure and Hirshfeld surface analysis of di-aqua-bis-(o-phenyl-enedi-amine-κ2N,N')nickel(II) naphthalene-1,5-di-sulfonate.

The reaction of o-phenyl-enedi-amine (OPD), sodium naphthalene1,5-di-sulfonate (Na2NDS) and nickel sulfate in an ethanol-water mixture yielded the title compound, [Ni(OPD)2(H2O)2]·NDS or [Ni(C6H8N2)2(H2O)2](C10H6O6S2). This salt consists of a complex [Ni(OPD)2(H2O)2]2+ cation with two bidentate OPD ligands and trans aqua ligands, and a non-coordinating NDS2- anion, which is the double-deprotonated form of H2NDS. The NiII atom is situated at a center of inversion and exhibits a slightly tetra-gonally distorted {O2N4} octa-hedral coordination environment, with four shorter equatorial Ni-N bonds [2.0775 (17) and 2.0924 (18) Å] and a longer axial Ni-O bond [2.1381 (17) Å]. The OPD ligand is located about an inversion center and is nearly coplanar with the NiN4 plane [dihedral angle 0.95 (9)°]. In the crystal, the cations and anions are connected by charge-assisted inter-molecular N-H⋯O and O-H⋯O hydrogen-bonding inter-actions into the tri-periodic network structure. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (44.1%), O⋯H/H⋯O (34.3%), C⋯H/H⋯C (14.8%) C⋯C (6.5%) (involving the cations) and O⋯H/H⋯O (50%), H⋯H (25%), C⋯H/H⋯C (15.3%), C⋯C (8.2%) (involving the anions) inter-actions.

Crystal structure and Hirshfeld surface analysis of 8-aza-niumylquinolinium tetra-chlorido-zincate(II).

The reaction of 8-amino-quinoline, zinc chloride and hydro-chloric acid in ethanol yielded the title salt, (C9H10N2)[ZnCl4], which consists of a planar 8-aza-n-ium-yl-quinolinium dication and a tetra-hedral tetra-chloro-zincate dianion. The 8-amino-quinoline moiety is protonated at both the amino and the ring N atoms. In the crystal, the cations and anions are connected by inter-molecular N-H⋯Cl and C-H⋯Cl hydrogen bonds, forming sheets parallel to (001). Adjacent sheets are linked through π-π inter-actions involving the pyridine and arene rings of the 8-aza-niumylquinolinium dication. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯Cl (48.1%), H⋯H (19.9%), H⋯C/C⋯H (14.3%) (involving the cations) and H⋯Cl (82.6%) (involving the anions) interactions.

Synthesis, structure and Hirshfeld surface analysis of a coordination compound of cadmium acetate with 2-amino-benzoxazole.

A first coordination compound of 2-amino-benzoxazole (2AB), namely, bis-(2-amino-benzoxazole-κN 3)bis-(acetato-κ2 O,O')cadmium(II), [Cd(CH3COO)2(2AB)2], has been synthesized from ethanol solutions of Cd(CH3(COO)2 and 2AB. In the monoclinic crystals with the space group C21/c, the cadmium ions coordinate two neutral 2AB mol-ecules in a monodentate fashion through the oxazole N atom, while two acetate ligands are coordinated through the O atoms in a bidentate manner. The coordination polyhedron of the central ion is substanti-ally distorted octa-hedral. There are two relatively strong intra-molecular hydrogen bonds in the complex mol-ecule. Additionally, two inter-molecular hydrogen bonds associate complex mol-ecules into columns running in the [10] and [110] directions. The Hirshfeld surface analysis shows that 45.7% of the inter-molecular inter-actions are from H⋯H contacts, 24.7% are from O⋯H/H⋯O contacts and 18.8% are from C⋯H/H⋯C contacts, while other contributions are from N⋯H/H⋯N and O⋯O contacts.

Synthesis, crystal structure, Hirshfeld surface analysis and DFT study of the 1,1'-(buta-1,3-diyne-1,4-di-yl)bis-(cyclo-hexan-1-ol).

The title compound, C16H22O2, was synthesized in order to obtain its guest-free form because 'wheel-and-axle'-shaped mol-ecules tend to crystallize from solutions as solvates or host-guest mol-ecules. It crystallizes in the monoclinic space group P2/c with two crystallographically non-equivalent mol-ecules, one situated on an inversion center and the other on a twofold axis. The rod-like 1,3-diyne fragments have the usual linear geometry. In the crystal, O-H ⋯ O bonds form eight-membered rings of the R 4 4(8) type, linking mol-ecules into layers. The Hirshfeld surface analysis indicates that the largest con-tributions are from inter-molecular H⋯H (ca 71%) and H⋯C/C⋯H (ca 19%) contacts. The energies of the frontier mol-ecular orbitals were determined by DFT calculations at the B3LYP/def2-TZVP level of theory.

Synthesis, crystal structure and Hirshfeld surface analysis of a cadmium complex of naphthalene-1,5-di-sulfonate and o-phenyl-enedi-amine.

A novel o-phenyl-enedi-amine (opda)-based cadmium complex, bis-(benzene-1,2-di-amine-κ2 N,N')bis-(benzene-1,2-di-amine-κN)cadmium(II) naphthalene-1,5-di-sulfonate, [Cd(C6H8N2)4](C10H6O6S2), was synthesized. The complex salt crystallizes in the monoclinic space group C2/c. The Cd atom occupies a special position and coordinates six nitro-gen atoms from four o-phenyl-enedi-amine mol-ecules, two as chelating ligands and two as monodentate ligands. The amino H atoms of opda inter-act with two O atoms of the naphthalene-1,5-di-sulfonate anions. The anions act as bridges between [Cd(opda)4]2+ cations, forming a two-dimensional network in the [010] and [001] directions. The Hirshfeld surface analysis shows that the primary factors contributing to the supramolecular inter-actions are short contacts, particularly van der Waals forces of the type H⋯H, O⋯H and C⋯H.

Tetra-aqua-(ethane-1,2-di-amine-κ2N,N')nickel(II) naphthalene-1,5-di-sulfonate dihydrate.

The reaction of ethane-1,2-di-amine (en, C2H8N2), the sodium salt of naphthalene-1,5-di-sulfonic acid (H2NDS, C10H8O6S2), and nickel sulfate in an aqueous solution resulted in the formation of the title salt, [Ni(C2H8N2)(H2O)4](C10H6O6S2)·2H2O or [Ni(en)(H2O)4](NDS)·2H2O. In the asymmetric unit, one half of an [Ni(en)(H2O)4]2+ cation and one half of an NDS2- anion, and one water mol-ecule of crystallization are present. The Ni2+ cation in the complex is positioned on a twofold rotation axis and exhibits a slight tetra-gonal distortion of the cis-NiO4N2 octa-hedron, with an Ni-N bond length of 2.0782 (16) Å, and Ni-O bond lengths of 2.1170 (13) Šand 2.0648 (14) Å. The anion is completed by inversion symmetry. In the extended structure, the cations, anions, and non-coordinating water mol-ecules are connected by inter-molecular N-H⋯O and O-H⋯O hydrogen bonding, as well as C-H⋯π inter-actions, forming a three-dimensional network.

Synthesis, crystal structure and Hirshfeld surface analysis of catena-poly[[bis-(semicarbazide-κ2 N,O)copper(II)]-µ-sulfato-κ2 O:O'].

The title polymer, [Cu(SO4)(CH5N3O)2] n , has been synthesized from aqueous solutions of CuSO4 and semicarbazide. In the crystal structure, the CuII atoms are chelated by two neutral semicarbazide mol-ecules through the oxygen atom and a nitro-gen atom of the amino group. The remaining two positions of the Jahn-Teller-distorted octa-hedral coordination sphere are occupied by oxygen atoms of two sulfate anions in the axial positions. The coordination bonds of the latter associate the polyhedra into polymeric chains running parallel to the c axis. There is a weak intra-molecular hydrogen bond between the N-H group and an oxygen atom of the SO4 2- anion. Thirteen relatively weak inter-molecular hydrogen-bonding inter-actions link the chains into a three-dimensional network. Hirshfeld surface analysis revealed that 64.7% of the inter-molecular inter-actions are from O⋯H/H⋯O contacts and 20.1% from H⋯H contacts. Other inter-actions such as N⋯H/H⋯N or C⋯H/H⋯C contribute less to the crystal packing.

2-Hy-droxy-ethyl-ammonium [2-(2,6-di-chloro-anilino)phen-yl]acetate monohydrate.

In the solid-state structure of the title compound derived from diclofenac, C2H8NO+·C14H10Cl2NO2 -·H2O, the asymmetric unit contains one cation, one anion and a water mol-ecule, all in general positions. A complex network of hydrogen bonds is present in the crystal structure.

Synthesis, crystal structure and Hirshfeld surface analysis of (1H-benzimidazol-2-yl)(morpholin-4-yl)methane-thione.

The title compound, C12H13N3OS, was synthesized via the Willgerodt-Kindler method. The benzimidozole moiety is essentially planar (r.m.s. deviation = 0.0084 Å). The thio-amide group is inclined by 54.80 (14)° to the benzimidazole ring system. The morpholine ring is disordered over two sets of sites [ratio 0.841 (11):0.159 (11)], with chair conformations for both components. In the crystal, mol-ecules are linked into N-H⋯N hydrogen-bonded chains running parallel to the c axis. Hirshfeld surface analysis was used to qu-antify the inter-molecular inter-actions.

Synthesis, crystal structure and Hirshfeld surface analysis of hexa-aqua-nickel(II) bis-(4-hy-droxy-benzoate) dihydrate.

The title compound, [Ni(H2O)6](PHB)2·2H2O (1) (PHB = 4-hy-droxy-benzoate, C7H5O3), was obtained by the reaction of NiCl2, 4-hy-droxy-benzoic acid (PHBA) and mono-ethano-lamine in aqueous ethanol solution. The NiII ion is coordinated by six water mol-ecules and is located on an inversion center. The outer coordination sphere in the asymmetric unit comprises one PHB anion and one water mol-ecule, i.e. the compound is a salt and a hydrate consisting of three components. In the crystal, the components are packed into an inter-molecular network stabilized by O-H⋯O hydrogen bonds. A comprehensive Hirshfeld surface analysis was carried out to investigate the inter-molecular inter-actions in detail.

Synthesis, crystal structure and Hirshfeld surface analysis of a zinc(II) coordination polymer of 5-phenyl-1,3,4-oxa-diazole-2-thiol-ate.

A new zinc coordination polymer with 5-phenyl-1,3,4-oxa-diazole-2-thiol-ate, namely, catena-poly[zinc(II)-bis-(µ2-5-phenyl-1,3,4-oxa-diazole-2-thiol-ato)-κ2 N 3:S;κ2 S:N 3], [Zn(C8H5N2OS)2] n , was synthesized. The single-crystal X-ray diffraction analysis shows that the polymeric structure crystallizes in the centrosymmetric monoclinic C2/c space group. The ZnII atom is coordinated to two S and two N atoms from four crystallographically independent (L) ligands, forming zigzag chains along the [001] direction. This polymer complex forms an eight-membered [Zn-S-C-N-Zn-S-C-N] chair-like ring with two ZnII atoms and two ligand mol-ecules. On the Hirshfeld surface, the largest contributions come from the short contacts such as van der Waals forces, including H⋯H, C⋯H and S⋯H. Inter-actions including N⋯H, O⋯H and C⋯C contacts were also observed; however, their contribution to the overall stability of the crystal lattice is minor.

The mol-ecular and crystal structures of 2-(3-hy-droxy-prop-yl)benzimidazole and its nitrate salt.

2-(3-Hy-droxy-prop-yl)-1H-benzimidazole, C10H12N2O, which has potential biological activity, can be used as a ligand for complexation with metals. This compound is an electron donor, due to the lone pair of the nitro-gen atom in the imidazole ring. This nitro-gen atom also acts as a proton acceptor. In the crystalline phase, the nitrate salt, namely, 2-(3-hy-droxy-prop-yl)-1H-benzim-id-azol-3-ium nitrate, C10H13N2O+·NO3 -, has been studied. The protonation of the 2-(3-hy-droxy-prop-yl)benzimidazole unit results in significant delocalization of the electron density within the imidazole ring. The salt formation leads to variations in the inter-molecular inter-actions, which were studied by analysis of the Hirshfeld surfaces and two-dimensional fingerprint plots.

Crystal structure, Hirshfeld surface analysis and DFT studies of tetra-kis-(µ-3-nitro-benzoato-κ2 O 1:O 1')bis-[(N,N-di-methyl-formamide-κO)copper(II)] di-methyl-formamide disolvate.

The title compound, [Cu2(C7H4NO4)4(C3H7NO)2]·(C3H7NO)2, is a binuclear copper(II) complex located on an inversion center midway between the two copper(II) cations. The asymmetric unit consists of one CuII cation, two 3-nitro-benzoato ligands, and two di-methyl-formamide (DMF) mol-ecules, one of which coordinates to the CuII cation and one is a solvate mol-ecule. The carboxyl-ate groups of the ligands bridge two CuII cations with a Cu-Cu distance of 2.6554 (6) Å, completing a distorted octa-hedral O5Cu coordination environment. The dihedral angles between the carboxyl-ate and the aromatic ring planes of the two independent ligands are different from one another, viz. 5.2 (3) and 23.9 (3)°. The three-dimensional structure is consolidated by weak C-H⋯O inter-actions and stabilized by π-π stacking inter-actions between the aromatic rings. The complex and the free ligand were further characterized by Fourier-transform infrared spectroscopy (FT-IR), and the energies of the frontier mol-ecular orbitals of the complex were determined by DFT calculations at the B3LYP/def2-TZVP level of theory.

Crystal structure and Hirshfeld surface analysis of the ortho-rhom-bic polymorph of a ZnII complex with 3,5-di-nitro-benzoic acid and ethyl-enedi-amine.

During systematic investigations of the biological action enhancement of well known compounds, a new metal complex, namely, bis-(3,5-di-nitro-benzoato)(ethane-1,2-di-amine)zinc(II), [Zn(C7H3N2O6)2(C2H8N2)], was synthesized and the structure of its ortho-rhom-bic form has determined. The synthesis and crystal structure of the monoclinic polymorph has previously been reported [Ibragimov et al. (2020 ▸). Rep. Uzb. Acad. Sci. 1, 45-50]. The zinc ion has a distorted tetra--hedral environment formed by two monodentate 3,5-di-nitro-benzoato anions and chelating ethyl-enedi-amine mol-ecule. In the crystal, the complex mol-ecules are linked by N-H⋯O and C-H⋯O hydrogen bonds into a two-dimensional network parallel to the ac plane. The Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯O/O⋯H (43.4%) and O⋯C/C⋯O (17.7%) inter-actions.

Crystal structure of tetra-µ-acetato-bis-[(5-amino-2-methyl-sulfanyl-1,3,4-thia-diazole-κN 1)copper(II)].

The reaction of 2-methyl-thio-5-amino-1,3,4-thia-diazole (Me-SNTD; C3H5N3S2) with copper(II) acetate monohydrate [Cu(OAc)2·H2O; C4H8CuO5] resulted in the formation of the title binuclear compound, [Cu2(C2H3O2)4(C3H5N3S2)2] or [Cu2(OAc)4(Me-SNTD)2]. The structure has triclinic (P ) symmetry with a crystallographic inversion centre located at the midpoint of the line connecting the Cu atoms in the dimer. These two Cu atoms of the dimer [Cu⋯Cu = 2.6727 (6) Å] are held together by four carboxyl-ate groups. Each Cu atom is further coordinated to the N atom of an Me-SNTD mol-ecule and exhibits a Jahn-Teller-distorted octa-hedral geometry. The dimers are connected into infinite chains by hydrogen bonds between the NH (Me-SNTD) and the carboxyl-ate groups of neighbouring mol-ecules, generating an R 2 2(12) ring motif. The mol-ecules are further linked by C-H⋯π inter-actions between the thia-diazole rings and the methyl groups of the acetate units.

Crystal structure of trans-bis-[2-(1H-benzotriazol-1-yl)acetato-κO]bis-(ethano-lamine-κ2 N,O)copper(II).

The reaction of 2-(1H-benzotriazol-1-yl)acetic acid (HBTA; C8H7N3O2) and mono-ethano-lamine (MEA; C2H7NO) with CuCl2·2H2O resulted in the formation of the title complex, [Cu(C8H6N3O2)2(C2H7NO)2] or [Cu(BTA)2(MEA)2]. Its asymmetric unit comprises one BTA anion coordin-ating to the Cu2+ cation (site symmetry ) through the carboxyl O atom, and one MEA ligand chelating the metal cation by two heteroatoms (O and N). The equatorial Cu-O and Cu-N bond lengths are similar at 2.029 (1) and 1.980 (2) Å, respectively, while the length of the axial Cu-O bond is considerably greater [2.492 (2) Å], as is typical for Jahn-Teller-distorted systems. An intra-molecular hydrogen bond is present between the hy-droxy group of the MEA ligand and the non-coordinating O atom of the carboxyl-ate group. Inter-molecular hydrogen bonding involving the amino function of the MEA ligand and the carboxyl-ate group results in eight-membered rings with an R 2 2(8) graph-set motif. The mol-ecules are further linked by C-H⋯π inter-actions involving the triazole rings and methyl-ene groups of MEA, thus generating an overall three-dimensional supra-molecular framework.

Conformational dimorphism in o-nitrobenzoic acid: alternative ways to avoid the O...O clash.

Polymorphism is a challenging phenomenon and the competitive packing alternatives which are characteristic for polymorphs may be encountered for essentially rigid molecules. A second crystal form of the well known compound o-nitrobenzoic acid, C7H5NO4, an important intermediate in the production of dyes, pharmaceuticals and agrochemicals, is described. Although obtained serendipitously, its intra- and intermolecular features match expectations from database searches and theoretical calculations. O-H...O hydrogen-bonded carboxylic acid dimers represent the building blocks in both polymorphs. For steric reasons and in agreement with a calculated potential energy surface, the carboxylic acid and nitro groups cannot simultaneously be coplanar with the benzene ring but have to tilt. In the well established crystal form, this out-of-plane torsion is more pronounced for the nitro substituent. In contrast, the new polymorph is characterized by a major tilt of the carboxylic acid group. The molecules in both alternative crystal forms achieve a similar compromise with respect to acceptable intramolecular O...O contacts.