Weak Intermolecular Contacts Research Articles

Crystal structure and Hirshfeld-surface analysis of an etoxazole metabolite designated R13

The etoxazole metabolite R13, systematic name 4-(4-tert-butyl-2-ethoxyphenyl)-2-(2,6-difluorophenyl)oxazole (C21H21F2NO2), results from the oxidation of etoxazole, a chitin synthesis inhibitor belonging to the oxazoline class, widely used as an insecticide/acaricide since 1998. The structure of R13 features a central oxazole ring with attached 2,6-difluorophenyl and 4-t-butyl-2-ethoxyphenyl moieties. The overall conformation gives dihedral angles between these rings and the oxazole of 24.91 (5)° (with difluorophenyl) and 15.30 (6)° (with t-butyl-ethoxyphenyl), indicating an overall deviation from planarity. Additionally, torsion angles of the ethoxy and t-butyl groups define the orientation of these substituents relative to their benzene ring. In the crystal packing, no significant hydrogen bonds are present, but a Hirshfeld surface analysis highlights weak intermolecular contacts leading to π–π-stacked dimers linked by weak C—H...N contacts. The packing analysis confirms that most intermolecular interactions involve hydrogen atoms.

Crystal structure of polymeric bis-(3-amino-1H-pyrazole)-cadmium diiodide.

The reaction of cadmium iodide with 3-amino-pyrazole (3-apz) in ethano-lic solution leads to tautomerization of the ligand and the formation of crystals of the title compound, catena-poly[[di-iodido-cadmium(II)]-bis-(μ-3-amino-1H-pyrazole)-κ2 N 2:N 3;κ2 N 3:N 2], [CdI2(C3H5N3)2] n or [CdI2(3-apz)2] n . Its asymmetric unit consists of a half of a Cd2+ cation, an iodide anion and a 3-apz mol-ecule. The Cd2+ cations are coordinated by two iodide anions and two 3-apz ligands, generating trans-CdN4I2 octa-hedra, which are linked into chains by pairs of the bridging ligands. In the crystal, the ligand mol-ecules and iodide anions of neighboring chains are linked through inter-chain hydrogen bonds into a di-periodic network. The inter-molecular contacts were qu-anti-fied using Hirshfeld surface analysis and two-dimensional fingerprint plots, revealing the relative qu-anti-tative contributions of the weak inter-molecular contacts.

Исследование кристаллических структур 7-иод-8-оксихинолин-5-сульфонатов алкилтрифенилфосфония [Ph3PAlk][OSO2C9NH4(I-7)(OH-8)], Alk = CH2Ph, CH=CHMe, CH2C≡CH

From alkyltriphenylphosphonium bromides and 7-iodo-8-hydroxyquinoline-5-sulfonic acid in water, ionic alkyltriphenylphosphonium 7-iodo-8-hydroxyquinoline-5-sulfonates Ph3PAlk][OSO2C9NH4(I-7)(OH-8)], Alk = CH2Ph (1), CH=CHMe (2), CH2C≡CH (3) have been obtained. Crystals 1 [C34H27NO4PSI, M 703.50; monoclinic system, symmetry group P21/c; cell parameters: a = 8.805(4), b = 16.146(10), c = 20.833(11) Å; β = 93.410(17), V = 2956(3) Å3, Z = 4; rcalc = 1.581 g/cm3], 2 [C30H25NO4PSI, M 653.44; rhombic system, symmetry group P212121; cell parameters: a = 9.382(3), b = 14.033(4), c = 21.035(6) Å; a = β = g = 90.00 deg., V = 2769.5(15) Å3, Z = 4; rcalc = 1.567 g/cm3], 3 [C30H27NO6PSI, M 687.46; monoclinic system, symmetry group P21/n; cell parameters: a = 9.426(3), b = 19.239(5), c = 16.088(5) Å; β = 97.296(14) deg., V = 2894.0(15) Å3, Z = 4; rcalc = 1.578 g/cm3]. According to the X-ray diffraction data, the phosphorus atoms in cations 1–3 have a distorted tetrahedral coordination, while the sulfonate anions have a regular geometry with a tetrahedral sulfur atom. The P–C bond lengths vary in the range 1.772(3)−1.815(2) Å; the CPC bond angles take values of 106.08(11)°−112.33(11)°. In the arenesulfonate anions of the complexes, the S–C distances are close to each other [1.781(2)–1.7920(19) Å], the S–O bonds are practically aligned [1.4464(16)–1.4590(17) Å]. In the crystal of hydrate 3 [Ph3PCH2C≡CH][OSO2C9NH4(I-7)(OH-8)] ∙ 2H2O, water molecules participate in formation of a dimeric anion (the O∙∙∙H and N∙∙∙H distances are 1.93 and 2.03 Å, while the arene rings of the sulfonate ligands are almost parallel (the angle between them is 3.24°)). Other water molecules link the dimeric anions into a chain with hydrogen bonds (the O∙∙∙H distances equal 2.12 and 2.15 Å). The structural organization in complexes 1–3 is mainly due to weak intermolecular contacts of the O···H type: 2.04–2.69 Å (1), 2.05–2.69 Å (2), 2.12–2.15 Å (3).

Self-Assembly and Conformational Change in the Oligomeric Structure of the Ectodomain of the TBEV E Protein Studied via X-ray, Small-Angle X-ray Scattering, and Molecular Dynamics

The determination of the three-dimensional structures of viral proteins is a necessary step both for understanding the mechanisms of virus pathogenicity and for developing methods to combat viral infections. This study aimed to explore the folding and oligomeric state of the major component of the virion surface of the tick-borne encephalitis virus (TBEV), the ectodomain of the envelope E protein (ectoE), which was expressed in E. coli in a soluble form and purified from inclusion bodies as a mixture of dimeric and monomeric forms. The time-dependent assembly of monomers into dimers was detected using size-exclusion chromatography. An X-ray diffraction study of the ectoE crystals grown at pH 4.5 confirmed the dimeric folding of the recombinant protein typical for ectoE. The ability of ectoE dimers to self-assemble into tetramers was detected via small-angle X-ray scattering (SAXS) in combination with molecular dynamics. Such self-assembly occurred at protein concentrations above 4 mg/mL and depended on the pH of the solution. In contrast to stable, specific dimers, we observed that tetramers were stabilized with weak intermolecular contacts and were sensitive to environmental conditions. We discovered the ability of ectoE tetramers to change conformation under crystallization conditions. These results are important for understanding the crystallization process of viral proteins and may be of interest for the development of virus-like particles.

Crystal structure of polymeric bis-(3-amino-1H-pyrazole)-cadmium dibromide.

The reaction of cadmium bromide tetra-hydrate with 3-amino-pyrazole (3-apz) in ethano-lic solution leads to tautomerization of the ligand and the formation of crystals of the title compound, catena-poly[[di-bromido-cadmium(II)]-bis-(μ-3-amino-1H-pyrazole)-κ2 N 3:N 2;κ2 N 2:N 3], [CdBr2(C3H5N3)2]n or [CdBr2(3-apz)2]n. Its asymmetric unit consists of a half of a Cd2+ cation, a bromide anion and a 3-apz mol-ecule. The Cd2+ cations are coordinated by two bromide anions and two 3-apz ligands, generating trans-CdN4Br2 octa-hedra, which are linked into chains by pairs of the bridging ligands. In the crystal, the ligand mol-ecules and bromide anions of neighboring chains are linked through inter-chain hydrogen bonds into a two-dimensional network. The inter-molecular contacts were qu-anti-fied using Hirshfeld surface analysis and two-dimensional fingerprint plots, revealing the relative qu-anti-tative contributions of the weak inter-molecular contacts.

Benzothiadiazolyl‐pyridine and ‐2,2′‐bipyridine Ligands for Luminescent and Magnetic Complexes

AbstractTwo new luminescent ligands, 4‐(2‐pyridine)‐7‐methyl‐2,1,3‐benzothiadiazole (L1) and 4‐(2,2‐bipyridine)‐7‐methyl‐2,1,3‐benzothiadiazole (L2), based on 2,1,3‐benzothiadiazole and pyridine or bipyridine were obtained by Suzuki coupling reactions. DFT and TD‐DFT type calculations have been performed on L1 and L2 in order to assign their experimental UV‐visible and emission bands. Reaction of L1 and L2 with metal(II) chlorides (M=Zn, Mn, Cu) provided the neutral complexes of formulas [ZnL1Cl2] (1), [Zn(L1)2Cl2] (2), [ZnL2Cl2] (3), [MnL2Cl2] ⋅ 0,5CH2Cl2 (4) and [CuL2Cl2] ⋅ H2O (5) which have been structurally characterized. The Zn(II) ions in 1 and 2 are four‐coordinate in somewhat distorted tetrahedral N2Cl2 surroundings with L1 adopting bidentate (1) and monodentate (2) coordination modes. Complexes 3–5 are isostructural and their metal atoms are five‐coordinate in distorted square pyramidal environments with three nitrogen atoms from the tridentate L2 ligand and a chlorine building the basal plane and another chlorine atom occupying the apical position. The three Zn(II) complexes are strongly luminescent in solution and the solid state, while the cryomagnetic study of the paramagnetic compounds 4 and 5 in the temperature range 2.9–300 K shows a Curie‐Weiss behaviour typical of small antiferromagnetic interactions which are mediated by weak intermolecular contacts.

Toward Near-Infrared Emission in Pt(II)-Cyclometallated Compounds: From Excimers’ Formation to Aggregation-Induced Emission

Two series of Pt(II)-cyclometallated compounds containing N^C^N tridentate and alkynyl-chromophore ligands have been synthesized and structurally characterized. The N^C^N ligands differ on the presence of R1 = H or F in the central aromatic ring, while six different chromophores have been introduced to the alkynyl moiety. Single-crystal X-ray structures for some of the compounds reveal the presence of weak intermolecular contacts responsible for the formation of some dimers or aggregates. The photophysical characterization shows the presence of two emission bands in solution assigned to the 3π-π* transition from the N^C^N ligands mixed with 3MLCT/3ILCT transitions (higher energy band) in deaerated samples. The formation of excimers has also been identified as a broad band at longer wavelengths [near-infrared (NIR) emission] that becomes the main emission band for compounds containing phenanthrene as the chromophore. NIR emission behavior has also been explored using acetonitrile/water mixtures, and the presence of aggregates that emit at ca. 650 nm has also been detected.

A combined crystallographic and theoretical investigation of noncovalent interactions in 1,3,4-oxadiazole-2-thione-N-Mannich derivatives: in vitro bioactivity and molecular docking.

Two 1,3,4-oxadiazole-2-thione-N-Mannich derivatives, specifically 5-(4-chlorophenyl)-3-[(2-trifluoromethylphenylamino)methyl]-1,3,4-oxadiazole-2(3H)-thione (1) and 5-(4-chlorophenyl)-3-[(2,5-difluorophenylamino)methyl]-1,3,4-oxadiazole-2(3H)-thione (2), were synthesized and then characterized by elemental analysis and NMR (1H and 13C) spectroscopy and the single crystal X-ray diffraction method. The formed weak intermolecular interactions in the solid-state structures of these derivatives were thoroughly investigated utilizing a variety of theoretical tools such as Hirshfeld surface analysis and quantum theory of atoms in molecules (QTAIM). Furthermore, the CLP-PIXEL and density functional theory calculations were used to study the energetics of molecular dimers. Numerous weak intermolecular interactions such as C-H⋯S/Cl/F/π interactions, a directional C-Cl⋯Cl halogen bond, π-stacking, type C-F⋯F-C contact and a short F⋯O interaction, help to stabilize the crystal structure of 1. Crystal structure 2 also stabilizes with several weak intermolecular contacts, including N-H⋯S, C-H⋯N//Cl/F interactions, a highly directional C1-Cl1⋯C(π) halogen bond and C(π)⋯C(π) interaction. In vitro antimicrobial potency of compounds 1 and 2 was assessed against various Gram-positive and Gram-negative bacterial strains and the pathogenic yeast-like Candida albicans. Both compounds showed marked activity against all tested Gram-positive bacteria and weak activity against Escherichia coli and lacked inhibitory activity against Pseudomonas aeruginosa. In addition, compounds 1 and 2 displayed good in vitro anti-proliferative activity against hepatocellular carcinoma (HepG-2) and mammary gland breast cancer (MCF-7) cancer cell lines. Molecular docking studies revealed the binding modes of title compounds at the active sites of prospective therapeutic targets.

Синтез и строение органосульфонатов тетраорганилфосфония [R4P][OSO2R’], R = Me, R’ = C6H3Cl2-2,5; R = Bu, R’ = C10H5(OH-1)(NO2)2-2,4; [Ph3PR][OSO2R’], R = CH2CH=CHCH2PPh3, R’ = OSO2C9H4N(OH-8)(I-7); R = C6H11-cyclo, R’ = C6H3(NO2)2-2,4; R = CH2CH=CHMe, R’ = C6H3Cl2-2,5

The interaction of equimolar amounts of tetraorganylphosphonium halides with 2,5-dichlorobenzenesulfonic, 2,4-dinitrobenzenesulfonic, 1-hydroxy-2,4-dinitro-7-naphthalenesulfonic and 8-hydroxy-7-iodo-5-quinolinesulfonic acids in water leads to the formation of ionic tetraorganylphosphonium organosulfonates [R4P][OSO2R’], R = Me, R’ = C6H3Cl2-2,5 (1); R = Bu, R’ = C10H5(OH-1)(NO2)2-2,4 (2); [Ph3PR][OSO2R’], R = CH2CH=CHCH2PPh3, R’ = C9H4N(OH-8)(I-7) (3); R = C6H11-cyclo, R’ = C6H3(NO2)2-2,4 (4); R = CH2CH=CHMe, R’ = C6H3Cl2-2,5 (5). The structures of complexes 1‒4 have been established by X-ray diffraction analysis. The X-ray structural analysis has been carried out on an automatic four-circle D8 Quest Bruker diffractometer (МоКα-radiation, λ = 0.71073 Å, graphite monochromator) at 293 K. Crystals 1 [C16H22O8PS2Cl4, M 579.23; monoclinic syngony, space group С2/с; сell parameters: a = 35.69(4), b = 7.454(9), c = 23.67(2) Å;  = 90.00, β = 129.16(3),  = 90.00 deg., V = 4883(9) Å3, Z = 8; calc = 1.576 g/cm3], 2 [C42H77N2O8P2S, M 832.06; orthorhombic syngony, space group Pbca; сell parameters: a = 14.712(9), b = 22.825(16), c = 29.475(16) Å;  = 90.00, β = 90.00,  = 90.00 deg., V = 9898(11) Å3, Z = 8; calc = 1.117 g/cm3], 3 [C29H27O6PSIN, M 675.45; triclinic syngony, space group P–1; сell parameters: a = 9.506(8), b = 11.323(12), c = 13.662(10) Å;  = 82.21(4), β = 89.26(2),  = 72.60(4) deg., V = 1390(2) Å3, Z = 2; calc = 1.614 g/cm3], and 4 [C30H29N2O7PS, M 592.58; triclinic syngony, space group P–1; сell parameters: a = 9.793(5), b = 11.214(5), c = 14.341(7) Å;  = 109.495(17), β = 99.55(3),  = 94.58(2) deg., V = 1448.5(12) Å3, Z = 2; calc = 1.359 g/cm3]. The coordination of the phosphorus atoms in cations 1‒5 is distorted tetrahedral; organosulfonate anions have the usual geometry with a tetrahedral sulfur atom. The Р−С bond lengths are 1.746(7)−1.841(19) Å, which is less than the sum of the covalent radii of the partner atoms (1.83 Å). The S−C distances are in the range of 1.759(5)−1.815(3) Å. The СРС valence angles vary in the range 85.2(8) −114.0(5) deg. The structural organization in crystals 1‒4 is due to weak intermolecular contacts of the O···Н type, 1.60–2.72 Å (the sum of the Van der Waals radii of the partner atoms is 2.62 Å). Complete tables of atomic coordinates, bond lengths and bond angles for structures have been deposited at the Cambridge Crystallographic Data Centre (No. 2153156 (1), No. 2157531 (2), No. 2160476 (3), No. 2157713 (4); deposit@ccdc.cam.ac.uk; https://www.ccdc.cam.ac.uk).

Реакции пентафенил- и пента(пара-толил)сурьмы с фумаровой кислотой

The interaction of pentaphenylantimony with fumaric acid in benzene (24 h, 24 С, molar ratio 4:3) gave a solvate with benzene Ph4SbOC(O)CH=CHC(O)OSbPh4 ∙ 2Ph4SbOC(O)CH=CHC(O)H ∙ 3PhH (1). At a molar ratio of the initial reagents of 2:1, the binuclear derivative of fumaric acid Ph4SbOC(O)CH=CHC(O)OSbPh4 (2) was formed. In similar reactions of penta(para-tolyl)antimony with fumaric acid, the adduct p-Tol4SbOC(O)CH=CHC(O)OSbTol4 ∙ HOC(O)CH=CHC(O)OH ∙ 4PhH (3) and the solvate of the binuclear derivative of fumaric acid with benzene p-Tol4SbOC(O)CH=СHC(O)OSbTol4 ∙ 3PhH (4) were formed, respectively. According to X-ray diffraction analysis performed at 293 K on a D8 Quest Bruker automatic four-circle diffractometer (two-coordinate CCD detector, Mo Kα radiation, λ = 0.71073 Å, graphite monochromator), the antimony atoms in crystals 1 [C63H53O6Sb2, M 1149.55; triclinic syngony, symmetry group P–1; cell parameters: a = 9.938(4), b = 14.999(8), c = 19.088(8) Å;  = 92.833(17), β = 102.148(16),  = 99.02(3) degrees; V = 2737(2) Å3; crystal size 0.3 × 0.17 × 0.05 mm; reflec-tion index intervals –13 ≤ h ≤ 13, –20 ≤ k ≤ 20, –25 ≤ l ≤ 25; total reflections 89119; independent reflections 14039; Rint = 0.0698; GOOF 1.070; R1 = 0.0442, wR2 = 0.0675; residual electron density 0.47/–0.80 e/Å3], 2 [C26H21O2Sb, M 487.18; monoclinic syngony, symmetry group С2/с; cell parameters: a = 28.35(3), b = 10.453(15), c = 17.49(2) Å; β = 93.01(5) degrees; V = 5176(12) Å3; crystal size 0.2×0.12×0.08 mm; reflection index intervals –26 ≤ h ≤ 30, –11 ≤ k ≤ 11, –19 ≤ l ≤ 13; total reflections 6329; independent reflections 3283; Rint = 0.1220; GOOF 1.318; R1 = 0.1253 wR2 = 0.3080; residual electron density 2.09–4.45 e/Å3], 3 [C88H86O8Sb2, M 1515.09; triclinic syngony, symmetry group P–1; cell parameters: a = 13.35(2), b = 13.50(2), c = 14.15(2) Å;  = 67.02(5), β = 62.29(6),  = 65.63(6) degrees; V = 1994(5) Å3; crystal size 0.55 × 0.33 × 0.28 mm; reflection index intervals –17 ≤ h ≤ 17, –17 ≤ k ≤ 17, –18 ≤ l ≤ 18; total reflections 54923; independent reflections 9183; Rint = 0.0604; GOOF 1.069; R1 = 0.0494, wR2 = 0.1159; residual electron density 1.83–1.68 e/Å3], 4 [C39H38O2Sb, M 660.44; triclinic syngony, symmetry group P-1; cell parameters: a = 11.328(6), b = 12.416(7), c = 12.997(6) Å;  = 82.24(2), β = 72.87(2),  = 75.50(3) degrees; V = 1687.5(15) Å3; crystal size 0.23×0.17×0.05 mm; reflection index in-tervals –14 ≤ h ≤ 14, –15 ≤ k ≤ 15, –16 ≤ l ≤ 16; total reflections 40178; independent reflections 7469; Rint 0.2589; GOOF 1.029; R1 = 0.0627, wR2 = 0.1275; residual electron density 0.95/–1.72 e/Å3], have a distorted trigonal-bipyramidal coordination with the carbon and oxygen atoms in axial positions (axial angles are 173.65(10), 175.74(11) for 1, 176.6(7)° for 2, 176.07(10)° for 3, 178.41(16)° for 4). The Sb–O distances are 2.253(2) and 2.240(2) Å for 1, 2.262(17) Å for 2, 2.302(3) Å for 3, and 2.234(4) Å for 4. The Sb–C bond lengths vary in a narrow range of values (2.110(3)–2.176(3) Å for 1, 2.114(2)–2.18(3) Å for 2, 2.109(5)–2.188(4) Å for 3, 2.113(5)–2.184(5) Å for 4). Structural organization in crystals is due to weak intermolecular contacts of the C=O•••H type (1.83–2.71 Å for 1, 1.81–2.71 Å for 3, 2.69 Å for 4). In crystals 1, 3, 4 the blocks of two dicarboxylic acids are linked to each other via the -C=O•••HOC(O)-chains (1.83, 1.83, 1.81 Å, respectively). Complete tables of atomic coordinates, bond lengths, and bond angles for the structures were deposited at the Cambridge Crystallographic Data Center (no. 2217281 for 1, (no. 2214920 for 2, no. 2220380 for 3, no. 2217063 for 4; deposit@ccdc.cam.ac.uk; https://www.ccdc.cam.ac.uk).

Dynamics of Formation of Binuclear Metal Complexes: A New Cu(I) Compound with N‐(2‐thiophenecarbonyl)‐N’‐(3‐Cl, 4‐F‐phenyl)thiourea as Ligand

AbstractHerein we report the synthesis and characterization of a new copper(I) complex with triphenylphosphine (PPh3) and N‐(2‐thiophenecarbonyl)‐N’‐(3‐Cl, 4‐F‐phenyl)thiourea (HL), as ligands. The complex was characterized by vibrational (FTIR and FT‐Raman) and multinuclear (1H, 13C {1H}, 31P{1H}) NMR spectroscopies. The crystalline structure of the complex was determined by single‐crystal X‐ray diffraction, confirming that a neutral binuclear compound, identified as [Cu(PPh3)(L‐κ2‐N,μ‐S)]2, was obtained. The anionic thiourea ligand coordinates to the metal through the sulfur and nitrogen atoms in an unusual bidentate κ2‐N,μ‐S coordination mode. The complex is a dimer sited on a crystallographic center of symmetry. Each Cu2(μ‐S)2 cation bridges trough the sulfur atoms of two symmetry related thiourea moieties and is also coordinated to the nitrogen atom of the thiourea ligand and the phosphorus atom from PPh3 co‐ligand, forming a slightly distorted tetrahedral geometry. An intramolecular N−H⋅⋅⋅O=C hydrogen bond is observed in the anionic ligand, forming a six‐membered ring that stabilizes the N−H thioamide group. Hirshfeld surface analysis shows that the molecules are connected by weak intermolecular contacts C⋅⋅⋅C, H⋅⋅⋅C and H⋅⋅⋅H which add to the stability of the crystalline packing. The in vitro cytotoxicity study of the complex indicates that it is more active against human lung carcinoma cells (A549), when compared to the free ligand.

A combined experimental and theoretical study on the synthesis, spectroscopic characterization of Magnesium(II) porphyrin complex with DMAP axial ligand and antifungal activity

We report in the present paper the synthesis, the spectroscopic, structural, and electrochemical properties of a new magnesium(II) coordination compound namely the bis(4-dimethylaminopyridine)[meso-tetra(p-tolyl)porphyrinato)]magnesium(II) dichloromethane disolvate complex with the formula [Mg(TTP)(DMAP)2]•2CH2Cl2 (I). This species crystallizes in the triclinic crystal system with the centrosymmetric space group P-1. The crystal lattice of (I) is stabilized by C__H…Cg (Cg is the centroid of a phenyl ring) and C__H…Cl intermolecular interactions. Further insights on these weak intermolecular contacts are provided by the Hirshfeld surface analysis. This new Mg(II) porphyrin species was characterized by 1H NMR, IR, fluorescence, UV/Vis spectroscopy and ESI-HRMS mass spectrometry. A cyclic voltammetry investigation of this new metalloporphyrin was also reported. Furthermore, the bioactivity of the H2TTP free base porphyrin, the [Mg(TTP)] starting material and [Mg(TTP)(DMAP)2]•2CH2Cl2 (I) was evaluated in vitro, by examining their inhibitory effect against three strains of Candida viz. C. albicans, C. glabrata and C. tropicalis with MIC values in the range 2.5 to 10 μg.mL−1. The screening of the susceptibility of M. canis and T. rubrum clinical strains on the three porphyrinic derivatives is also reported.

Synthesis, characterization and catalytic studies of chromium(III) porphyrin complex with axial cyanate ligands

We report the synthesis and the spectroscopic, structural and electrochemical characterization of a new chromium(III) coordination compound namely the bis(cyanato-κN)[meso-tetratolylporphyrinato]chromate(III) (cryptand-222)potassium dihydrate [K(crypt-222)][CrIII(TTP)(NCO)2]·2H2O (complex I). This compound crystallizes in the orthorhombic crystal system with the non-centrosymmetric space group C2221. The chromium and the potassium atoms are located at special positions in a two-fold axis. The crystal lattice of complex I is stabilized by O__H…O, C__H…O, C__H…N and C__H…π intermolecular contacts involving the negatively charged [CrIII(TTP)(NCO)2]− species, the [K(crypt-222)]+ counterions and the two non-coordinated water molecules. Further insights on these weak intermolecular contacts are provided by the Hirshfeld surface analysis. Molecular electrostatic potential (MEP) theoretical calculation on [K(crypt-222)][CrIII(TTP)(NCO)2]·2H2O are reported. The new Cr(III) complex was efficient as a catalyst in the decomposition of the Rhodamine B (RbH) dye by hydrogen peroxide. This coordination compound was also tested as a photocatalyst of the photodecomposition of the RbH dye by molecular oxygen.

Isolation and Identification of Pseudo Seven-Coordinate Ru(III) Intermediate Completing the Catalytic Cycle of Ru-bda Type of Water Oxidation Catalysts

Isolation and Identification of Pseudo Seven-Coordinate Ru(III) Intermediate Completing the Catalytic Cycle of Ru-bda Type of Water Oxidation Catalysts

A Crystallographic, Spectroscopic, and Computational Investigation of Carbonyl and Oxalyl Diisothiocyanate.

Carbonyl diisothiocyanate (1) and oxalyl diisothiocyanate (2) were synthesized by reactions of phosgene and oxalyl chloride with ammonium thiocyanate, respectively. Their structures were elucidated by single-crystal X-ray diffraction. 1 exhibits weak intermolecular S-O contacts forming a loosely connected network of molecules, whereas 2 exhibits weak intermolecular Ccarbonyl-O contacts resulting in the formation of layers. Both compounds were further characterized by nuclear magnetic resonance, infrared, and Raman spectroscopy. Quantum-chemical calculations reproduced the experimental structures and enabled the interpretation of the vibrational spectra.

ON THE INFLUENCE OF WEAK INTERMOLECULAR INTERACTIONS ON THE MOLECULAR CRYSTAL DENSITY OF 1,3,5-TRIAZINE TRINITROALKYL DERIVATIVES

It is well known that the densest molecular crystals formed by molecules consisting of C, H, N, O, and F atoms are those of polynitro compounds that do not and cannot participate in strong intermolecular interactions. At the same time, many ''typical'' organic crystals are also stabilized by weak intermolecular contacts, such as C–H···O(N), O(N)···π, H···H, and so forth. However, the density of such crystals is significantly lower. In this work, we report the synthesis and properties of 1,3,5-triazine derivatives containing both trinitromethyl and/or trinitroethoxy, as well as isopropoxy groups. It was shown by X-ray structural analysis and quantum chemistry calculations that the crystal structures of the obtained 1,3,5-triazine derivatives were stabilized by weak interactions only, such as NO 2 ···NO 2 , O···π, C–H···O, C–H···N, and H···H contacts. The effects from various types of weak intermolecular contacts on crystal density were evaluated. No strong correlation was found between the energy of interactions, decrease of system volume caused by such interactions, and an increase in crystal density. It was demonstrated that crystal packing can be studied effectively by a recently proposed method via the analysis of Δ OED criterion describing the density increase of molecule and its fragments upon crystal formation from isolated molecules.

On the influence of weak intermolecular interactions on the molecular crystal density of 1,3,5-triazine trinitroalkyl derivatives

It is well known that the densest molecular crystals formed by molecules consisting of C, H, N, O, and F atoms are those of polynitro compounds that do not and cannot participate in strong intermolecular interactions. At the same time, many “typical” organic crystals are also stabilized by weak intermolecular contacts, such as C–H···O(N), O(N)···π, H···H, and so forth. However, the density of such crystals is significantly lower. In this work, we report the synthesis and properties of 1,3,5-triazine derivatives containing both trinitromethyl and/or trinitroethoxy, as well as isopropoxy groups. It was shown by X-ray structural analysis and quantum chemistry calculations that the crystal structures of the obtained 1,3,5-triazine derivatives were stabilized by weak interactions only, such as NO2···NO2, O···π, C–H···O, C–H···N, and H···H contacts. The effects from various types of weak intermolecular contacts on crystal density were evaluated. No strong correlation was found between the energy of interactions, decrease of system volume caused by such interactions, and an increase in crystal density. It was demonstrated that crystal packing can be studied effectively by a recently proposed method via the analysis of ΔOED criterion describing the density increase of molecule and its fragments upon crystal formation from isolated molecules.

Crystal structure and energetic features of the cocrystal of carbamazepine with 3,5-dinitrobenzoic acid.

The synthesis and detailed description of the crystal structure and energetic features of the 1:1 cocrystal of carbamazepine (5H-dibenzo[b,f]azepine-5-carboxamide, CBZ) with 3,5-dinitrobenzoic acid (35DNBA), i.e. C15H12N2O·C7H4N2O6, are reported. The CBZ and 35DNBA molecules are packed in alternately arranged layers. Two characteristic R22(8) and R22(16) hydrogen-bond ring motifs have been found. The supramolecular architecture, besides the network of hydrogen bonds, is also stabilized by numerous C-H...π, C=O...π, N-O...π, N-O...C and C=O...N weak intermolecular contacts involving neighbouring molecules in the crystal network. Identified interactions have been discussed in detail on the basis of a structural and energetic analysis. The latter approach, performed using the Pixel and CrystalExplorer programs, yielded additional information about the lattice energy and energetic landscape of the respective interactions in the crystal of CBZ·3DNBA with the evaluation of electrostatic, polarization, repulsion and dispersion terms.

2-Methyl-4-(4-nitro-phen-yl)but-3-yn-2-ol: crystal structure, Hirshfeld surface analysis and computational chemistry study.

The di-substituted acetyl-ene residue in the title compound, C11H11NO3, is capped at either end by di-methyl-hydroxy and 4-nitro-benzene groups; the nitro substituent is close to co-planar with the ring to which it is attached [dihedral angle = 9.4 (3)°]. The most prominent feature of the mol-ecular packing is the formation, via hy-droxy-O-H⋯O(hy-droxy) hydrogen bonds, of hexa-meric clusters about a site of symmetry . The aggregates are sustained by 12-membered {⋯OH}6 synthons and have the shape of a flattened chair. The clusters are connected into a three-dimensional architecture by benzene-C-H⋯O(nitro) inter-actions, involving both nitro-O atoms. The aforementioned inter-actions are readily identified in the calculated Hirshfeld surface. Computational chemistry indicates there is a significant energy, primarily electrostatic in nature, associated with the hy-droxy-O-H⋯O(hy-droxy) hydrogen bonds. Dispersion forces are more important in the other identified but, weaker inter-molecular contacts.

Synthesis, crystal structure, Hirshfeld Surface analysis, and DFT studies of 16-ferrocenylidene-17β-estra-1,3,5-triene-3,17-diol: Towards the application of ferrocene-hormone conjugates to target hormone dependent breast cancer

The ferrocene-hormone conjugate 16-ferrocenylidene-17β-estra-1,3,5-triene-3,17-diol crystallizes in a monoclinic unit cell, space group P21. The asymmetric unit cell contains two ferrocene-hormone conjugates, co-crystallized with two water and one acetonitrile molecules. The crystal structure shows a hydrogen bonding network within the hormone residues and the co-crystallized water and acetonitrile molecules. Hirshfeld surface and two-dimensional fingerprint plots were performed for each of the ferrocene-hormone conjugates in order to analyse weak intermolecular contacts. Particular attention is placed on hydrogen bond interactions in the crystal structure. A noncovalent OH-π intermolecular interaction was found in the crystal structure. DFT studies were employed using the long-range functional ωB97XD and 6–311 g** basis set to study such interactions. The existence of this OH-π intermolecular interaction contributes with −2.32 kcal/mol to the total energy of the crystalline structure.