In the title compound, C22H20O3, the dihedral angles between the central and peripheral aromatic rings are 83.47 (2) and 66.00 (2)° and the packing is consolidated by C-H⋯π inter-actions. Hirshfeld surface analysis indicates that the major contributions to the two-dimensional fingerprint plots arise from H⋯H (51.1%), C⋯H/H⋯C (32.7%), and H⋯O/O⋯H (14.3%) contacts. Energy framework calculations indicate that dispersion energy makes the largest contribution (-240 kJ mol-1) to the packing compared to the other energy components.
In the title salt, (C5H6N)[ZnCl3(C5H5N)], the Zn2+ atom is four-coordinated by one pyridine N atom and three chloride ligands, forming a slightly distorted tetra-hedral ZnNCl3 environment. In the crystal, the cation and anion are linked by bifurcated N-H⋯(Cl,Cl) and C-H⋯Cl hy-dro-gen bonds, generating a supra-molecular assembly that is further consolidated by π-π stacking inter-actions between aromatic rings. Hirshfeld surface analysis shows that H⋯Cl/Cl⋯H contacts are the dominant contribution to the crystal packing, accounting for 44.1% of the total surface contacts, followed by H⋯H (29.9%) and H⋯C/C⋯H (15.0%) inter-actions.
The reaction of (4-bromo-benz-yl)tri-phenyl-phospho-nium bromide ([4BrBzTPP][Br]) with excess perchloric, tetra-fluoro-boric or hydro-iodic acid in methanol affords the corresponding anion-exchanged salts. X-ray quality crystals of (4-bromo-benz-yl)tri-phenyl-phospho-nium perchlorate, C25H21BrP+·ClO4 - or [4BrBzTPP][ClO4], (I), (4-bromo-benz-yl)tri-phenyl-phospho-nium tetra-fluoro-borate, C25H21BrP+·BF4 - or [4BrBzTPP][BF4], (II), and (4-bromo-benz-yl)tri-phenyl-phospho-nium triiodide, C25H21BrI3P+·I3 - or [4BrBzTPP][I3], (III), were isolated and characterized by single-crystal X-ray diffraction. Compounds (I) and (II) are isostructural and crystallize in the ortho-rhom-bic space group Pbca, whereas compound (III) crystallizes in the monoclinic space group P21/n. In all three structures, the phospho-nium cation adopts a tetra-hedral geometry at phospho-rus, with C-P-C bond angles in the range 106.09 (11)-112.67 (11)°. Hirshfeld surface analyses show that H⋯H and H⋯C contacts dominate the environments of the (4-bromo-benz-yl)tri-phenyl-phospho-nium cations, whereas the perchlorate, tetra-fluoro-borate and triiodide anions are linked to the surrounding cations primarily through H⋯O, H⋯F and H⋯I contacts, respectively.
The asymmetric unit of the title compound, [Cu2I2(C6H8N2)] n , consists of six crystallographically independent CuI cations, six unique iodide anions and three independent 2,6-di-methyl-pyrazine ligands, all of them located in general positions. Three of the six copper cations display trigonal planar coordinations (one 2,6-di-methyl-pyrazine ligand and two iodide ions), whereas the remaining cations are tetra-hedrally coordinated (one 2,6-di-methyl-pyrazine ligand and three iodide ions). In the extended structure, two different CuI substructures are observed. In one of them, discrete (CuI)4 units are observed, which show a ladder-like arrangement. Two of the cations are threefold, the other two cations are fourfold coordinated and are linked by two μ-1,1 and two μ-1,1,1 bridging iodide anions. In the other substructure (CuI)2 rings built up of one threefold and one fourfold coordinated copper cation as well as one μ-1,1 and one μ-1,1,1 bridging iodide anion are connected into chains. These CuI substructures are linked by bridging 2,6-di-methyl-pyrazine ligands into layers that lie parallel to the ab plane. The layers are connected by a number of C-H⋯I inter-actions. Analyzing the CuI substructures in related copper(I) iodide coordination compounds with pyrazine deriv-atives as neutral ligands revealed that the same ladder-like CuI substructure is observed in all of them, which is completely different from that observed in the title compound.
The title compound, C13H14Cl2N2S, consists of di-chloro-phenyl and di-hydro-pyrimidine-thione rings, where the pyrimidine ring is in a flattened-boat conformation. In the crystal, N-H⋯S hydrogen bonds link the mol-ecules, enclosing R 2 2(8) ring motifs, into centrosymmetric dimers. Neither π-π stacking nor C-H⋯π(ring) inter-actions are observed. Hirshfeld surface analysis revealed that the most important contributions for crystal packing are from H⋯H (40.8%), H⋯Cl/Cl⋯H (28.7%) and H⋯S/S⋯H (15.5%) inter-actions. The volume of the crystal voids and the percentage of free space were calculated to be 135.01 Å3 and 17.99%, showing the crystal packing is not compact. Computational methods indicated an N-H⋯S hydrogen-bonding energy of -58.2 kJ mol-1. Evaluations of the electrostatic, dispersion and total energy frameworks indicate that the crystal cohesion is dominated by electrostatic energy contributions.
The solid-state structure of the adduct of di-phenyl-tin(IV) hydroxide chloride, Ph2Sn(OH)Cl, with 2-vinyl-pyridine, 2Vipy, namely, di-μ-hydroxido-bis-[chlorido-diphenyl-tin(IV)]-2-ethenyl-pyridine (1/2), [Sn2(C6H5)4Cl2(OH)2]·2C7H7N, exhibits dimeric, hydrogen-bonded aggregates [Ph2Sn(OH)Cl·2Vipy]2. The aggregates are non-centrosymmetric but exhibit the characteristic structural features of Brønsted base, BB, stabilized diorganotin(IV) hydroxide-halides, [R 2Sn(OH)Hal·BB]2, with trigonal-bipyramidally coordinated tin atoms and two bridging hydroxide groups. Non-centrosymmetry leads to a slightly bent and distorted rhombic, four-membered Sn2-O2 ring consisting of two different tin and oxygen atoms. As usual, Sn-O bond lengths depend on the position the hydroxyl groups adopt within the trigonal-bipyramidal coordination sphere of the Sn atoms [mean values: d(Sn-OH)ax = 2.191 (9) Å, d(Sn-OH)eq = 2.019 (3) Å]. Bond angles within the Sn2-O2 ring are acute [mean value: 71.1 (2)°] at the tin atoms and obtuse [mean value: 108.9 (3)°] at the oxygen atoms. Hydroxyl groups display a trigonal-planar constitution and are involved in hydrogen bonds [mean values: d(O⋯N) = 2.714 (8) Å; <(O-H⋯N) = 170 (5)°] to the N atoms of the 2-vinyl-pyridine mol-ecules.
Titanium(IV) chloride was reacted with a slight excess of barium penta-fluoro-phenoxide in tetra-hydro-furan (THF) solution. After filtration and solvent evaporation, the resulting orange crystalline material was obtained. The product was recrystallized by preparing a concentrated solution in THF at room tem-per-a-ture, followed by cooling to 253 K. The supernatant solution was deca-nted using a pipet, and the crystals were dried by allowing the solvent to evaporate in the atmosphere of a glovebox. It was possible to obtain good-quality X-ray data at 100 K on a crystal, namely, tetra-kis-(penta-fluoro-phenoxido-κO)bis-(tetra-hy-dro-furan-κO)titanium(IV), [Ti(C6F5O)4(C4H8O)2], having monoclinic (P21/n) symmetry. This com-pound adopts a solid-state structure in which the titanium(IV) ions have a distorted octa-hedral coordination environment with two coordinated THF mol-ecules occupying cis positions.
The title com-pound, C25H28N4O2, crystallizes in space group P1 with Z = 4. The two independent mol-ecules are related by the approximate translation (x + 1, y + 1, z), but differ in the orientation of the phenyl substituent. Crystals are non-merohedrally twinned by a 180° rotation about c*. In the modified chromene ring systems, the two formal double bonds are the shortest C-C bonds. The oxo ring displays a flattened boat conformation, whereas the other ring is approximately a flattened envelope, with the CMe2 C atom out of the plane. The mol-ecules are connected by classical N-H⋯Npyrazole hy-dro-gen bonds to form a ribbon of alternating independent mol-ecules parallel to [110]. The ribbons are joined by weak Cpyrazole-H⋯Nnitrile hy-dro-gen bonds to form a layer structure parallel to the ab plane in the region z ≃ 3/4.
The title compound, bis-(imidazolidine-2-thione-κS)di-thio-cyanato-cobalt(II), [Co(NCS)2(C3H6N2S)2], was prepared by the reaction of cobalt thio-cyanate with ethyl-ene-thio-urea in ethanol solution. The asymmetric unit (space group P21/c) consists of one cobalt cation, as well as two crystallographically independent thio-cyanate anions and two ethyl-ene-thio-urea ligands, all of them located in general positions. The metal cations are tetra-hedrally coordinated by two N-bonding anionic ligands and two ethyl-ene-thio-urea ligands into discrete complexes. These complexes are linked by N-H⋯S hydrogen bonds into layers. The IR spectrum is in agreement with the presence of a tetra-hedral coordination with N-bonding thio-cyanate anions and measurements using X-ray powder diffraction indicate that a pure crystalline phase has been obtained. The title compound represents a new isomer of Co(NCS)2(C3H6N2S)2, which was already reported in the literature in space group P1 [Mautner et al., (2018 ▸). Polyhedron 154, 436-442]. In contrast to the title compound, in the triclinic isomer the cobalt cations are octa-hedrally coordinated and linked into chains by μ-1,3-bridging thio-cyanate anions. Solvent-mediated conversion experiments starting from a mixture of both isomers show that the title complex is the thermodynamically stable form at room temperature.
A crystallography educational outreach activity was developed and implemented in the US kindergarten level (K) (5–6 years old), which included writing and illustrating a new children's book about crystallography titled, X-ray Crystallography Adventures! Cat & Elephant's Sugar Crystal Mystery. The outreach activity included four rotating centers that encompassed hands-on crystallization experiments, observing crystals under microscopes, learning about the crystallography process through coloring, and connecting crystallography to life through reading. Detailed descriptions of the centers and overall activity should enable the ready adoption of this model by others for encouraging young children to engage with and learn about crystallography. >
A new mixed alkali-metal borate, poly[[sodium rubidium [hydroxido-octa-μ-oxido-penta-borate] monohydrate], NaRbB5O8(OH)·H2O, has been synthesized via a surfactant-thermal method using H3BO3, Rb2CO3, Na2SiO3·9H2O, ethanedi-amine and poly(ethyl-ene glycol)-400 as starting materials. It features a layered boron-oxide framework constructed from penta-borate [B5O10(OH)]6- building units. Adjacent single layers are inter-connected to form double layers through hydrogen-bonding inter-actions. Na+, Rb+ cations and H2O mol-ecules are located in the voids of the framework.
Cocrystallization of norfloxacin (NFX) with three heterocyclic coformers, namely, pyridine-3,5-dicarboxylic acid, pyridazine-3-carboxylic acid and pyrimidine-5-carboxylic acid, yielded three molecular salts: norfloxacinium [4-(3-carboxy-1-ethyl-6-fluoro-4-oxo-1,4-dihydroquinolin-7-yl)piperazin-1-ium] 5-carboxypyridine-3-carboxylate trihydrate, 2C 16 H 19 FN 3 O 3 + ·2C 7 H 4 NO 4 − ·3H 2 O, ( 1 ), norfloxacinium pyridazine-3-carboxylate, C 16 H 19 FN 3 O 3 + ·C 5 H 3 N 2 O 2 − , ( 2 ), and norfloxacinium pyrimidine-5-carboxylate monohydrate, C 16 H 19 FN 3 O 3 + ·C 5 H 3 N 2 O 2 − ·H 2 O, ( 3 ). In all structures, the quinolone skeleton of the norfloxacin cation is essentially planar, while the piperazine ring adopts a chair conformation. The crystal packing is governed primarily by N—H...O and N—H...N hydrogen bonds, which generate distinct mono-periodic and di-periodic motifs depending on the coformer. These assemblies are further linked by weak C—H...O and C—H...N interactions into tri-periodic supramolecular networks. The crystal structures are additionally stabilized by aromatic π–π interactions, which differ in their stacking arrangements among the three salts. Hirshfeld surface analysis of the norfloxacin cations shows that H...H and O...H/H...O contacts dominate, whereas variations in the contributions from C...C, C...H/H...C and N...H/H...N contacts reflect differences in the supramolecular packing.
The title isomorphous copper(I) coordination complexes, bis(μ-4-methyl-1 H -1,2,4-triazole-5-thiolato)bis[chlorido(triphenylphosphane)copper(II)], [Cu 2 (C 3 H 5 N 3 S) 2 Cl 2 (C 18 H 15 P) 2 ], and bis(μ-4-methyl-1 H -1,2,4-triazole-5-thiolato)bis[bromido(triphenylphosphane)copper(II)], [Cu 2 (C 3 H 5 N 3 S) 2 Br 2 (C 18 H 15 P) 2 ], were synthesized from copper(I) halide salts and a mixed-ligand system containing Hmptrz and PPh 3 in acetonitrile (Hmptrz = 4-methyl-1 H -1,2,4-triazole-5-thione and PPh 3 = triphenylphosphine). The asymmetric unit comprises one-half of the dinuclear complex, with each copper(I) center exhibiting a distorted tetrahedral coordination geometry defined by one halide ion, one phosphorus atom from PPh 3 , and two μ-S bridging from Hmptrz bridging molecules. The two μ-S bridges [Cu—S—Cu ≃ 70.2°] connect pairs of copper(I) atoms to generate a lozenge-shaped, centrosymmetric Cu 2 S 2 core. In the extended structure C—H... X ( X = Cl or Br) hydrogen bonds link the dimers into a three-dimensional supramolecular architecture. Hirshfeld surface and two-dimensional fingerprint plot analyses were also carried out to investigate and quantify the intermolecular contacts governing the crystal packing.
The crystal structure of the title compound {systematic name: [bis(prop-2-en-1-yl)carbamodithioato-κ 2 S , S ′](2-methylquinoline-κ N )zinc(II)}, [Zn(C 7 H 10 NS 2 ) 2 (C 10 H 9 N)] the heteroleptic complex reveals supramolecular dimers established by π–π interactions between adjacent quinaldine units with a centroid–centroid distance of 3.672 (2) Å. The compound crystallizes in the triclinic crystal system, space group P 1 , with the Zn II atom exhibiting a trigonal–bipyramidal geometry.
The title compound, [CdBr 2 (C 6 H 8 N 2 )] n , was prepared by the reaction of cadmium bromide with 2,3-dimethylpyrazine in acetonitrile. Powder X-ray diffraction (PXRD) indicated that a pure phase had been obtained. The asymmetric unit consists of one Cd cation located on a center of inversion, one 2,3-dimethylpyrazine ligand situated on a twofold rotation axis and one bromide anion in a general position. In the extended structure, the cadmium cation is octahedrally coordinated by four bridging bromide anions and two bridging 2,3-dimethylpyrazine coligands. The cations are linked via common bromide-ion edges into [010] chains that are further connected into (100) layers by the bridging 2,3-dimethylpyrazine coligands. Measurements using thermogravimetry and differential thermoanalysis reveal that the compound decomposes in two separate steps in which a more 2,3-dimethylpyrazine-deficient compound is formed, which according to PXRD measurements is crystalline.
The title menthol-derived ester, C 19 H 26 O 4 , was synthesized by chloroacetylation of menthol followed by reaction with sodium benzoate. It crystallizes in the Sohncke space group P 2 1 with one molecule in the asymmetric unit. The cyclohexane ring adopts a chair conformation, and the benzoate fragment is essentially planar. The oxoethyl bridge shows a gauche conformation about the O—CH 2 bond and an anti conformation about the CH 2 —C bond. In the crystal, the packing is mainly consolidated by a weak C—H...O contact linking molecules into chains parallel to [100]. Hirshfeld surface analysis indicates that H...H contacts make the largest contribution to the crystal cohesion, followed by O...H/H...O and C...H/H...C contacts, consistent with the hydrophobic menthyl entity. DFT calculations show reasonable agreement between the refined and optimized structures. Frontier-orbital and electrostatic-potential analyses identify the benzoate ester and carbonyl oxygen atoms as the main electronically active regions.
The title compound, [Co(NCS) 2 (C 6 H 4 N 2 ) 2 (H 2 O) 2 ], is isotypic to its Ni analog and to one of the two modifications of Mn(NCS) 2 (4-cyanopyridine)(H 2 O) 2 reported recently [Näther (2026). Acta Cryst. E 82 , 441–445 and Wellm et al. (2020). Cryst. Growth Des. 20 , 3374–3385]. Its asymmetric unit is built up of one cobalt cation that occupies a center of inversion, one thiocyanate anion, one neutral 4-cyanopyridine coligand and one water molecule that are located in general positions. The metal cations are sixfold coordinated by two terminally N-bonding thiocyanate anions, two water molecules and two 4-cyanopyridine coligands within a slightly distorted octahedral geometry. The discrete complexes are linked by intermolecular O—H...S hydrogen bonding into layers that condense into a three-dimensional network via weak C—H...N interactions. Powder X-ray diffraction (PXRD) proves that a pure sample has been obtained. Thermogravimetric measurements reveal that the title compound decomposes in different steps, in which compounds with the composition Co(NCS) 2 (4-cyanopyridine) 2 and Co(NCS) 2 (4-cyanopyridine) are formed as intermediates, which are not isotypic to the corresponding Mn compounds already reported in the literature [Wellm et al. (2020). Cryst. Growth Des. 20 , 3374–3385].
The title compound, C 17 H 18 N 4 O 4 , consists of almost planar isatin and triazole rings inclined by 78.47 (5)°, as well as a butyl acetate moiety bonded to the N atom of the triazole ring. In the crystal, molecules link into a semicolon shape along the b -axis direction through bifurcated C—H...O hydrogen bonds. Aromatic π–π and C—H...π(ring) interactions also help to consolidate the crystal packing. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H...H (40.6%), H...O/O...H (26.6%), H...N/N...H (13.8%) and H...C/C...H (8.9%) interactions. The volume of the crystal voids and the percentage of free space in the unit cell were calculated to be 82.1 Å 3 and 10.0%, respectively, showing that there is no large cavity in the crystal packing. Computational methods revealed C—H...O hydrogen-bonding energy of −11.6 kJ mol −1 . The evaluation of the electrostatic, dispersion and total energy frameworks indicates that the stabilization is dominated via the dispersion energy contributions in the crystal structure.
Two N -alkyl derivatives of 2-methoxy-5-nitroaniline, namely, 2-methoxy- N -(4-methylbenzyl)-5-nitroaniline (C 15 H 16 N 2 O 3 , orange crystals) and 2-methoxy-5-nitro- N -(triphenylmethyl)aniline ethanol quatersolvate (C 26 H 22 N 2 O 3 ·0.25C 2 H 5 OH, yellow crystals), have been prepared and analyzed by single-crystal X-ray diffraction to determine if these compounds display the same face-to-face π-stacking arrangement as observed in the un-alkylated parent compound. The triphenylmethyl derivative crystallizes with 0.25 ethanol molecules, the contribution of which has been modeled with a solvent mask due to a high degree of disorder. The UV-Vis spectra show that the benzyl derivative displays concentration-dependent shifts in the visible portion of the spectrum, shifting to longer wavelengths with higher concentration, which is attributed to aggregation in solution. This behavior is similar to that observed for the parent compound. In contrast, the triphenylmethyl derivative shows an attenuated concentration dependence on visible absorption, which does not display as great a red shift, and therefore represents a lesser tendency for aggregation in solution. The crystal packing for these compounds is distinguishing, with the benzyl derivative π-stacking in a face-to-face manner with dipole moments oriented anti-parallel, while the sterically demanding triphenylmethyl group prevents direct π-stacking for this compound. The packing observed for these compounds supports the hypothesis that an intermolecular charge-transfer process is responsible for the orange color of crystals of the benzyl derivative. It is concluded that sterically undemanding groups attached at the amino group could deliver materials which mimic the color center formation hypothesized for the parent compound. These types of structural changes may have useful applications in the field of organic semiconductors.
In the title salt, C 14 H 14 N 3 + ·NO 3 − , the cation is almost planar (r.m.s. deviation = 0.014 Å), implying significant conjugation of the lone pair of the tertiary amino group N atom with the aromatic ring system. In the extended structure, N—H...O and C—H...O hydrogen bonds link the components into infinite chains of alternating cations and anions propagating along the b -axis direction. Aromatic π–π stacking interactions with centroid–centroid distances of 3.5773 (12) and 3.5889 (12) Å may help to consolidate the packing. Hirshfeld surface analysis revealed that the most important contributions for the crystal packing are from H...H (39.2%), H...O/O...H (31.6%), H...C/C...H (10.3%) and C...C (9.1%) interactions.
