The synthesis and crystal structure of (4<Emphasis Type="Italic">E</Emphasis>)-5(3-chlorophenyl)-<Emphasis Type="Italic">N</Emphasis>-(4-chlorophenyl)-2-diazo3-oxopent-4-enoic acid amide

(4E)-5-(3-Chlorophenyl)-N-(4-chlorophenyl)-2-diazo-3-oxopent-4-enoic acid amide (5) was synthesized from p-chloroaniline to N-(4-chlorophenyl)-2-diazo-3-oxo-butyramide (4) with 3-chlorobenzaldehyde. The yielded product 5 was investigated with X-ray crystallographic, NMR, MS, and IR techniques. Compound 5 (C₁₇H₁₁Cl₂N₃O₂, Formula wt = 360.19), crystallizes in the monoclinic space group P21/c with unit cell parameters a = 10.516(2), b = 17.996(4), c = 8.902(2) Å, α = 90.00, β = 105.36(3), γ = 90.00^°. V = 1624.5(6) ų, Z = 4, D _x = 1.473 Mg m^?3. The final R was 0.0511.     

Crystallization,crystal-structure refinement,and IR spectroscopy of a synthetic hexahydroborite analog

The crystal structure of the hexahydroborite analog Ca[B(OH)₄]₂ · 2H₂O (a = 7.9941(3) Å, b = 6.6321(2) Å, c = 7.9871(3) Å, β = 104.166(4)°, V = 410.58(3) ų, sp. gr. P2/c, Z = 2, ρ_calc = 1.891 g/cm³; Xcalibur S CCD automated diffractometer, 1196 reflections with I > 2σ(I), λMoK _α), which was synthesized by the hydrothermal method via the recrystallization of calciborite CaB₂O₄ (M) in the M ? B₂O₃ ? H₂O system (t = 250°C and P = 70–80 atm), was refined by the least-squares method with anisotropic displacement parameters (H atoms were located; R ₁ = 0.0260). The structure of synthetic hexahydroborite consists of infinite columns running along the c axis. The columns are formed by Ca polyhedra linked together and to [B(OH)₄] orthotetrahedra by sharing edges. Along the two other axes, the translationally equivalent columns are linked only by hydrogen bonds. The presence of a stronger bond between the discrete (Ca-B-O) columns along the shortest (b = 6.6 Å) axis accounts for the possibility of the shift of the columns by 1/2T _b and the formation of the second modification of Ca[B(OH)₄]₂ · 2H₂O. The crystals of synthetic hexahydroborite were studied by IR spectroscopy. A crystal-chemical analysis was performed for a series of natural metaborates with the general formula CaB₂O₄ · nH₂O (CaO: B₂O₃ = 1: 1, n = 0–6), including calciborite CaB₂O₄ and hexahydroborite CaB₂O₄ · 6H₂O as the end members.     

Synthesis,structural characterization,and DFT calculations of 3-buthyl-4-(3-methyl-3-mesitylcyclobut-1-yl)-1,3-thiazole-2(3<Emphasis Type="Italic">H</Emphasis>)-thione

The title compound, C₂₁H₂₉NS₂, has been synthesized and its crystal structure has been determined from single crystal X-ray diffraction data. Crystals are monoclinic, a = 11.4923(8), b = 13.1842(7), c = 14.6583(8) Å, β = 109.983(6)°, sp. gr. P2₁/c, Z = 4. Mesityl and thiazole groups are in cis positions with respect to the cyclobutane ring. The cyclobutane ring is puckered, with a dihedral angle of 26.6(2)° between the two three-atom planes. The crystal structure involves one weak intermolecular C–H···S hydrogen-bond. The molecular geometry was also optimized using density functional theory (DFT/B3LYP) method with the 6-311G(d, p) basis set in ground state. Geometric parameters (bond lengths, bond angles and torsion angles) and vibrational assignments have been calculated theoretically and compared with the experimental data.     

Coordination dimers constructed from metal(II) halides and the organic ligand 1,2-dimethoxy- 4,5-bis(2-pyridylethynyl)benzene

A series of new coordination compounds has been synthesized using the organic ligand 1,2-dimethoxy-4,5-bis(2-pyridylethynyl)benzene (dmpeb). The compounds all form dimers consisting of two metal cations bridged by two ligand molecules. Charge balance is provided by halide ligands, and the four-coordinate metal centers are distorted from the ideal tetrahedral environment. [CoCl₂(dmpeb)]₂ (1) crystallizes in the monoclinic space group P2₁/n with a = 8.5272(6) Å, b = 18.3653(13) Å, c = 13.3493(9) Å, β = 103.574(2)^°, V = 2032.2(2) ų, Z = 2. [ZnCl₂(dmpeb)]₂ (2) is isostructural to 1 and has the cell parameters a = 8.5495(4) Å, b = 18.4049(8) Å, c = 13.3692(6) Å, β = 103.4460(10)^°, V = 2046.01(16) ų, Z = 2. [ZnBr₂(dmpeb)]₂ (3) is also isostructural to 1 with a = 8.7882(5) Å, b = 18.7260(12) Å, c = 13.3857(8) Å, β = 102.5990(10)^°, V = 2149.8(2) ų, Z = 2. Additionally, the compounds [ZnI₂(dmpeb)]₂ (4, cell parameters: a = 8.9650(5) Å, b = 19.1251(10) Å, c = 13.4160(7) Å, β = 101.1660(10)^°, V = 2256.7(2) ų, Z = 2), [HgCl₂(dmpeb)]₂ (5, cell parameters: a = 8.8457(7) Å, b = 18.4030(15) Å, c = 13.3711(11) Å, β = 104.246(2)^°, V = 2109.7(3) ų, Z = 2), and [HgBr₂(dmpeb)]₂ (6, cell parameters: a = 9.0576(5) Å, b = 18.8634(11) Å, c = 13.4535(8) Å, β = 102.9780(10)^°, V = 2239.9(2) ų, Z = 2) are also isostructural to 1. A seventh dimeric compound, [HgI₂(dmpeb)]₂, not isostructural to the others was also characterized by X-ray crystallography. [HgI₂(dmpeb)]₂ (7) crystallizes in the triclinic space group P-1 with a = 8.8028(5) Å, b = 12.0990(7) Å, c = 12.4082(7) Å, α = 109.7240(10)^°, β = 107.3680(10)^°, γ = 93.0880(10)^°, V = 1169.57(12) ų, Z = 1.     

Synthesis and characterization of 9-(4-nitrophenyl)3,3,6,6-tetramethyl-3,4,6,7,9,10-hexahydro-1,8(2H,5H) acridinedione and its methoxyphenyl derivative

9-(4-Nitrophenyl)-3,3,6,6-tetramethyl-3,4,6,7,9,10-hexahydro-1,8(2H,5H) acridinedione (NTHA) crystallizes in orthorhombic space group P2₁2₁2₁ with a = 5.9716(1) Å, b = 18.0476(3) Å, c = 19.2445(2) Å, V = 2074.04(5) ų, Z = 4, D_cal = 1.263 Mg m^?3 and R = 0.0521 (wR = 0.1326) for 4078 observed reflections. 9-(4-Nitrophenyl)-10-(4-methoxyphenyl)-3,3,6,6-tetramethyl-3,4,6,7,9,10-hexahydro-1,8(2H,5H) acridinedione NMTHA, crystallizes in monoclinic space group P2₁/c with a = 15.669(5) Å, b = 10.652(4) Å, c = 18.337(6) Å, β = 108.25(1)^°, V = 2906.66(2) ų, Z = 4, D_cal = 1.245 Mg m^?3 and R = 0.0725 (wR = 0.1847) for 5105 observed reflections. The experimental values are compared with the theoretical values calculated based on the semiemperical methods. The structures are stabilized by N–H?sO and C–H?sO types of intermolecular interactions in addition to van der Waals forces.     

Unclassical hydrogen bonds of C—H⋅<Emphasis Type="Italic">s</Emphasis>O and C—H⋅<Emphasis Type="Italic">s</Emphasis>N in the crystals of 2-amino-3-cyano-4-(3,4-dichlorophenyl)-5-oxo-1,4,5,6-tetrahydro-4H-pyrano[2,3-<Emphasis Type="Italic">d</Emphasis>]pyrimidine

The 2-amino-3-cyano-4-(3,4-dichlorophenyl)-5-oxo-1,4,5,6-tetrahydro-4H-pyrano[2,3-d] pyrimidine (1, C₁₇H₁₅Cl₂N₅O₃) was synthesized and characterized by IR,¹H NMR and elemental analysis. The molecular structure of1 was further studied by using X-ray crystallography. The crystals of compound1 are triclinic, space groupP-1,a = 6.0090(4) Å,b = 10.4056(7) Å,c = 15.6021(11) Å, α = 70.983(4), β = 84.056(6), γ = 84.611(6),Z = 2,V = 915.47(11) ų. Two types of unclassical hydrogen bonds C–H?sO and C–H?sN were presented in the crystals. In addition, there were classical hydrogen bonds in the crystal structure.     

Synthesis,antityrosinase activity of curcumin analogues,and crystal structure of (1<Emphasis Type="Italic">E</Emphasis>,4<Emphasis Type="Italic">E</Emphasis>)-1,5-bis(4-ethoxyphenyl)penta-1,4-dien-3-one

Five derivatives of curcumin analogue (R = OCH₂CH₃ (1), R = N(CH₃)₂ (2), R = 2,4,5-OCH₃ (3), R = 2,4,6-OCH₃ (4), and R = 3,4,5-OCH₃ (5)) were synthesized and characterized by ¹H NMR, FT-IR and UV–Vis spectroscopy. The synthesized derivatives were screened for antityrosinase activity, and found that 4 and 5 possess such activity. The crystal structure of 1 was determined by single crystal X-ray diffraction: monoclinic, sp. gr. P2₁/c, a = 17.5728(15) Å, b = 5.9121(5) Å, c = 19.8269(13) Å, β = 121.155(5)°, Z = 4. The molecule 1 is twisted with the dihedral angle between two phenyl rings being 15.68(10)°. In the crystal packing, the molecules 1 are linked into chains by C?H···π interactions and further stacked by π···π interactions with the centroid–centroid distance of 3.9311(13) Å.     

Synthesis,thermal analysis,and crystal structure of manganese(II) 9-molybdocobaltate(III)

Manganese(II) 9-molybdocobaltate(III) of the composition [Mn(H₂O)₄] · [CoMo₉O₂₇(OH)₅] · 7H₂O (I) has been synthesized for the first time and investigated using X-ray diffraction and thermal gravimetric analyses. Compound I crystallizes in the trigonal system with the following unit cell parameters: a = 15.926(1) Å, c = 12.363(1) Å, V = 2715.6(4) ų, M = 1692.55, Z = 3, ρ_(calcd) = 3.105 g/cm³, space group R32.     

Investigation of the crystallization features,atomic structure,and microstructure of chromium-doped monticellite

A series of Cr⁴⁺:CaMgSiO₄ single crystals is grown using floating zone melting, and their microstructure, composition, and crystal structure are investigated. It is shown that regions with inclusions of second phases, such as forsterite, akermanite, MgO, and Ca₄Mg₂Si₃O₁₂, can form over the length of the sample. The composition of the single-phase regions of the single crystals varies from the stoichiometric monticellite CaMgSiO₄ to the solid solution Ca_{(1 ? x)}Mg_{(1 + x)}SiO₄(x = 0.22). The Cr:(Ca_0.88Mg_0.12)MgSiO₄ crystal is studied using X-ray diffraction. It is revealed that, in this case, the olivine-like orthorhombic crystal lattice is distorted to the monoclinic lattice with the parameters a = 6.3574(5) Å, b = 4.8164(4) Å, c = 11.0387(8) Å, β = 90.30(1)^o, Z = 4, V = 337.98 ų, and space group P2₁/c. In the monoclinic lattice, the M(1) position of the initial olivine structure is split into two nonequivalent positions with the center of symmetry, which are occupied only by Mg²⁺ cations with the average length of the Mg-O bond R _av = 2.128 Å. The overstoichiometric Mg²⁺ cations partially replace Ca²⁺ cations (in the M(2) position of the orthorhombic prastructure) with the average bond length of 2.347 Å in the [(Ca,Mg)-O₆] octahedron. The average distance in SiO₄ distorted tetrahedra is 1.541 Å.     

Synthesis,Crystal Structure,and Free Radical Scavenging Activity of 4-Aminopyridinium 3,5-Dinitrobenzoate

The crystal structure of 4-aminopyridinium 3,5-dinitrobenzoate, C₁₂H₁₀O₆N₄, has been determined by single-crystal X-ray diffraction technique. The title compound crystallizes in the monoclinic sp. gr. P21/n with the unit cell parameters: a = 7.4726(3) Å, b = 23.0898(9) Å, c = 8.0744(4) Å, V = 1338.64(10) ų, Z = 4. The asymmetric unit of the compound consists of one 3,5-dinitrobenzoate anion and 4-aminopyridine cation. The adjacent anions and cations are linked through two N?H···O hydrogen bonds, N2?H2A···O5 and N₂?H2B···O6, to form an infinite chain of anions and cations, extended along the [010] direction.     

Molecular structures of chalcone podands: A prognosis of photoinduced transformations in the crystals

A series of chalcone podands with the propenone group in the ortho position of the bridging aryl substituent with respect to the oxyethylene fragment is synthesized. The influence of the preorganization of the chalcone podand molecules in crystals on their ability to participate in topochemical reactions is investigated. From analyzing the X-ray structural data, the highest probability of the solid-state photochemical [2 + 2]cycloaddition is predicted for podands with phenyl substituents and the oxyethylene fragment containing two or three oxygen atoms. The X-ray structural data for the chalcone podand C₃₂H₂₆O₄ (3a) are as follows: a = 7.904(9) Å, b = 14.92(2) Å, c = 21.30(3) Å, β = 91.7(1)°, monoclinic system, space group P2₁/c, Z = 4, V = 2510(5) ų, ρ = 1.26 g/cm³, and R = 0.046; C₃₄H₃₀O₅ (3b): a = 15.738(9) Å, b = 11.889(2) Å, c = 15.0830(15) Å, β = 105.47(14)°, monoclinic system, space group C2/c, Z = 4, V = 2720.0(9) ų, ρ = 1.266 g/cm³, and R = 0.0418; C₃₂H₂₄N₂O₈ (4a): a = 17.9416(18) Å, b = 10.9703(8) Å, c = 41.699(2) Å, β = 105.970(11)°, monoclinic system, space group P2₁/c, Z = 4, V = 2781.4(5) ų, ρ = 1.348 g/cm³, and R = 0.0426; C₃₆H₃₂N₂O₁₀ (4c): a = 7.6286(5)Å, b = 17.9398(10) Å, c = 11.5890(3)Å, β = 95.287(4)°, monoclinic system, space group P2₁/n, Z = 2, V = 1579.27(14) ų, ρ = 1.372 g/cm³, and R = 0.0377; and C₂₈H₂₂O₆ (5a): a = 15.6032(10) Å, b = 8.1131(5) Å, c = 17.7334(11) Å, β = 91.381(5)°, monoclinic system, space group C2/c, Z = 4, V = 2244.2(2) ų, ρ = 1.345 g/cm³, and R = 0.0309.     

Crystal structure,physical properties and Pt-195 NMR characterization of Pt(bipy)Br

The complex dibromobipyridylplatinum(II), Pt(bipy)Br₂, crystallizes in the monoclinic space groupC2/c witha = 17.262(5) Å,b = 9.388(2) Å,c = 7.557(2) Å, β = 113.47(2)^°, andZ = 4. The complex is isomorphous to the monomeric copper derivative, Cu(bipy)Br₂. The¹⁹⁵Pt NMR spectrum shows the typical line broadening effect caused by coordinated nitrogen-14. The complex resonates at ?1897 ppm with a half-height peak width of 1300 Hz. The structure is compared with the analogous structures Pt(bipy)(X)₂ (X = Cl and I) and Pd(bipy)Br₂.     

Synthesis and crystal structure of <Emphasis Type="Italic">N</Emphasis>-(6methoxylbenzothiazol-2-yl)-1-(4-fluorophenyl)<Emphasis Type="Italic">O</Emphasis>,<Emphasis Type="Italic">O</Emphasis>-dipropyl-<Emphasis Type="Italic">α</Emphasis>-aminophosphonate

Molecular and crystal structure of N-(6-methoxybenzothiazol-2-yl)-1-(4-fluorophenyl)-O,O-dipropyl-α-aminophosphonate, C₂₁H₂₆FN₂O₄PS, have been determined by single-crystal X-ray diffraction study. The title compound is tetragonal, with a = 21.35(3) Å, c = 20.16(5) Å, Z = 16, D _x = 1.308 Mg/m³, μ(MoKα) = 0.247 mm^?1, and space group is I4₁/a. The structure was solved by direct method and refined to a final R = 0.0687 for 2370 reflections with I > 2σ(I). The compound shows a fully delocalized benzothiazole system with a sp² hybridization of the N(2). There is a strong intermolecular hydrogen bond between P=O and NH. The crystal structure is stabilized by a strong intermolecular N–H?sO hydrogen bond.     

X-ray diffraction study of thiocarbamide hydrochloride

Thiocarbamide hydrochloride single crystals forming a salt with the composition [(NH₂)₂CSH]⁺Cl^? are studied by the X-ray diffraction method. The tetragonal crystals have the unit-cell parameters a = 7.556(1) Å and c = 18.329(3) Å, V = 1046.5 ų, Z = 8, ρ_calcd = 1.436 g/cm³, sp. gr. P4₁2₁2, and R = 0.050. Each chloride anion in the crystal forms five hydrogen bonds with thee different cations.     

Crystal structure of a new synthetic Ca,Li pentaborate: CaLi<Subscript>4</Subscript>[B<Subscript>5</Subscript>O<Subscript>8</Subscript>(OH)<Subscript>2</Subscript>]<Subscript>2</Subscript>

When studying the phase formation in the CaO-Li₂O-B₂O₃-H₂O system, a new Ca,Li pentaborate was synthesized under hydrothermal conditions. The structure of a new compound with the crystallochemical formula CaLi₄[B₅O₈(OH)₂]₂ (sp. gr. Pb2n, a = 8.807(7), b = 9.372(7), c = 8.265(6) Å, V = 682.2(9) ų, Z = 2, d_calcd = 2.43 g/cm³, automated SYNTEX-\(P\bar 1\) diffractometer, 2690 reflections, 2θ/θ scan, λMo) is refined up to R_hkl = 0.0557 in the anisotropic approximation of atomic thermal vibrations with allowance for the localized H atoms. The structure of the Ca,Li pentaborate is formed by (010) open boron—oxygen layers formed by two independent [B₅O₈(OH)₂]^3? pentagroups, with each of them being formed by three B tetrahedra and two B triangles. The structure framework consists of the above boron—oxygen layers bound by isolated Li tetrahedra. The Ca cations are localized in the centers of eight-vertex polyhedra located in the [001] channels of the Li,B,O framework. Comparative crystallochemical analysis of the new Ca,Li pentaborate and Li pentaborate of the composition Li₃[B₅O₈(OH)₂]-II showed that the anionic matrices of both compounds are completely identical, whereas some of the cationic positions are different.     

Investigation of structural transformations in pyridine nitrate at low temperatures and high pressures

The structural transformations in pyridine nitrate PyHNO₃ (C₅D₅NHNO₃) are investigated by neutron diffraction in the temperature range 16–300 K at normal pressure and in the high-pressure range 0–3.5 GPa at room temperature. A new high-pressure phase with a monoclinic structure (space group P2₁/c) is revealed in the PyHNO₃ compound at pressures P > P_tr ～ 1 GPa. The geometry of hydrogen bonds and the coordination of the PyH⁺ and NO ₃ ^? ions in the structure of the PyHNO₃ compound are studied as a function of the temperature and pressure.     

Structure of 1-(2,6-dimethylphenyl)-<Emphasis Type="Italic">N</Emphasis>-hydroxy-4,4-dimethyl-2,5-dioxo-<Emphasis Type="Italic">N</Emphasis>-phenyl-3-pyrrolidine carboxamide

The title compound is crystallized in the monoclinic space group P2₁/c with cell parameters a = 7.499, b = 13.336, c = 19.390 Å, β = 99.716°, V = 1911.4 ų, Z = 4, D _cal = 1.273 Mg/m³ at T = 120 K. The structure is refined by full-matrix least-squares procedures to final R ₁ = 0.0548 and wR ₂ = 0.1089 for 3424 reflections. Two phenyl rings are noncoplanar with regard to each other and pyrrolidine core. The structure contains intramolecular hydrogen bond.     

Synthesis and Crystal Structure Studies of a Novel Bioactive Heterocycle: 1-Benzhydryl-4-phenylmethane Sulfonyl Piperazine

1-Benzhydryl-4-phenylmethane sulfonyl piperazine was synthesized from 1-benzhydryl piperazine with phenylmethane sulfonyl chloride. The product obtained was characterized by ¹H NMR, MS and IR techniques and finally confirmed by X-ray crystallography. The title compound C₂₄H₂₆N₂O₂S, M _r   =   406.53, crystallizes in the orthorhombic crystal class in the space group Pbca with unit cell parameters a  =  11.1240(10)Å, b  =   9.4940(15)Å, c  =  40.239(4)Å, Z  =  8 and V = 4249.7(9)ų. The structure was solved by direct methods and refined to R ₁=0.0561 for 2,445 reflections with [I > 2 σ(I)]. The piperazine ring adopts a chair conformation. The sulfonyl moiety is in a distorted tetrahedral configuration.     

Unstrained bond lengths and corresponding cation radii in crystals with perovskite structure

A method for determining average lengths of unstrained bands A-X (l_0AX) and B-X (l_0BX) and the ratio of the rigidity constants of these bonds for ABX₃ compounds with perovskite structure is proposed. The values of l_0AX and l_0BX correspond to the minimum energies of cation-anion interaction of the crystal sublattices. Values of l_0AX and l_0BX are obtained for several groups of halide and oxide compounds: A⁺B²⁺F₃, Cs⁺B²⁺Cl₃, A⁺B⁵⁺O₃, A²⁺B⁴⁺O₃, and A³⁺B³⁺O₃. It is ascertained that, for most compounds studied, the values of l_0AX and l_0BX are equal or close to the interatomic distances in crystals of binary compounds. The values of l_0AX and l_0BX are compared with the sums of the radii of the corresponding cations (R _A , R _B ) and anions (\(^{VI} R_{O^{2 - } } ,^{VI} R_{F^ - } ,^{VI} R_{Cl^ - }\)). It is found that the differences \(l_{0AO^ - } ^{VI} R_{O^{2 - } } (L_{0AF^ - } ^{VI} R_{F^ - } )\) and \(l_{0BO^ - } ^{VI} R_{O^{2 - } } (l_{0BF^ - } ^{VI} R_{F^ - } )\), regarded as the radii of the A and B cations in unstrained bonds, are close to the Shannon radii for a coordination number of six. It is shown that the rigidity constant for A-X bonds is several times smaller than that for B-X bonds.     

Synthesis and Electrical Properties of a Fluorite-Like Nd<Subscript>5</Subscript>Mo<Subscript>3</Subscript>O<Subscript>16</Subscript> Compound with Partial Substitution of Molybdenum by Tungsten,Niobium, or Vanadium

The phase formation of Nd₅Mo_{3 – x}W _x O_16.5, Nd₅Mo_{3 – x}Nb _x O_{16.5 – х/2}, and Nd₅Mo_{3 – x}V _x O_{16.5 – х/2} solid solutions based on a fluorite-like Nd₅Mo₃O_16.5 compound (mixed conductor with interstitial oxygen conductivity) has been studied. The electrical conductivity of doped compounds obeys the Arrhenius law and, at a low impurity content, is as high as 0.03–0.08 S/cm at 800°C. Substitution of Mo⁶⁺ cations by V⁵⁺ and Nb⁵⁺ cations reduces the interstitial oxygen content, which causes a decrease in the solid-solution electrical conductivity by 1–2 orders of magnitude and a decrease in the cubic unit-cell parameter. A wide diffuse anomaly with a maximum of about 1500–4000 has been observed in the temperature dependence of the permittivity for all single-crystal and polycrystalline samples in the range of 300–900°C.