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1.
Guanidine dichloroacetate was synthesized and separated as crystals. Differential scanning calorimetry (DSC) measurement shows that this compound undergoes a reversible phase transition at about 275 K with a heat hysteresis of 28 K. Step-like dielectric anomaly observed at 274 K further confirms the phase transition. The single-crystal X-ray diffraction data suggested that these was a transition from a room-temperature phase with the space group of P21/n (a = 8.030(5), b = 12.014(9), c = 8.124(6) Å, β = 96.089(1)°, V = 779.3(1) Å3, and Z = 4) to a low-temperature one with the space group of P21/c (a = 7.941(2), b = 11.828(3), c = 10.614(2) Å, β = 130.985(1)°, V = 752.6(3) Å3, and Z = 4). The displacements of hydrogen bonds induce the structure phase transition.  相似文献   

2.
The crystal structures of four organoselenium compounds, viz. bis(2-formylphenyl)diselenide (5), bis(2-methylnaphthyl)diselenide (6), organoselenenyl sulfide (7), and spiroselenurane (8) are described. Crystal data for 5: space group Pca21, crystal system orthorhombic, a=7.9969(4) Å, b=20.8794(12) Å, c=15.8307(13) Å, Z=8, R=0.0292. Owing to the presence of a strong Se···O interaction in compound 5 the geometry around the selenium atom may be considered as T-shaped. Crystal data for 6: space group Pna21, crystal system orthorhombic, a=18.2253(12) Å, b=13.0714(8) Å, c=7.7355(5) Å, Z=4, R=0.0570. The molecule has a cisoid conformation. Crystal data for 7: space group Pbcn, crystal system orthorhombic, a=22.2144(13) Å, b=8.0255(4) Å, c=15.4496(9) Å, Z=8, R=0.0292. Due to intramolecular Se···N interaction in 7 the geometry around selenium is T- shaped. Crystal data for 8: space group P21/c, crystal system monoclinic, a=7.4585(5) Å, b=19.5634(13) Å, c=8.0428(5) Å, β=97.1320(10)°, Z=4, R=0.0254. The O?Se?O angle is 172.86(6)°.  相似文献   

3.
The structure of bis(N,N,N′,N′-tetramethylthiophosphoramidoyl)-methylamine 1 has been determined by single-crystal X-ray diffraction. The compound 1 crystallizes in the monoclinic system, with a space group P21/c, a = 11.836(2) Å, b = 11.659(2) Å, c = 12.796(5) Å and β = 95.28(3)°, V = 1758.3(5) Å3 and Z = 4. The X-ray crystallographic data have been assessed by semi-empirical and ab-initio density functional theory and by Hartree–Fock molecular orbital methods. A comparative study of the results of the different methods is given.  相似文献   

4.
Two thiosemicarbazones, (E)-2-(2,4-dimethoxybenzylidene)thiosemicarbazone (24-MBTSC (1)) and (E)-2-(2,5-dimethoxybenzylidene)thiosemicarbazone (25-MBTSC (2)), derived from 2,4-dimethoxybenzaldehyde and 2,5-dimethoxybenzaldehyde, respectively, with thiosemicarbazide have been synthesized and their structures were characterized by elemental analyses, FT-IR, 1H NMR spectroscopy, and X-ray single-crystal diffraction analysis. Molecular orbital calculations have been carried out for 1 and 2 by using an ab initio method (HF) and also density functional method (B3LYP) at 6-31G basis set. Compound 1 crystallizes in the monoclinic system, space group P21/c, with a = 8.1342(5) Å, b = 18.1406(10) Å, c = 8.2847(6) Å, β = 109.7258(17)°, V = 1150.75(12) Å3, and Z = 4, whereas compound 2 crystallizes in the orthorhombic system, space group Pbca, with a = 11.0868(6) Å, b = 13.1332(6) Å, c = 15.9006(8) Å, V = 2315.2(2) Å3, and Z = 8. The compounds 1 and 2 displays a trans-configuration about the C=N double bond.  相似文献   

5.
Two napelline skeletal diterpenoid alkaloids 15-acetylsongorine, C24H33NO4 I, and songoramine, C22H29NO3 II, were first isolated from the roots of Aconitum Szechenyianum Gay. The crystal structures were determined by X-ray single-crystal diffraction analysis. The crystal I is the triclinic system with space group P1 having unit cell parameters of a = 9.360(8) Å, b = 11.593(9) Å, = 11.830(16) Å, α = 113.223(15)°, β = 105.950(16)°, γ = 101.296(12)°, and Z = 2. Hydrogen bonds O–H···O and O–H···N joint the molecules into dimer. The crystal II belongs to the orthorhombic system with space group P212121 having unit cell parameters of a = 8.950(2) Å, = 13.272(3) Å, = 15.454(4) Å and Z = 4. The O–H···O hydrogen bonding interaction links the molecule into linear chains. The distortion of rings of compound I and II were evaluated by calculation of the Cremer and Pople puckering parameters. The presence of the C–O–C bond in the compound II results in the changes of ring conformations compared with that of the compound I.  相似文献   

6.
A new high-nitrogen complex [Cu(Hbta)2]·4H2O (H2bta = N,N-bis-(1(2)H-tetrazol-5-yl) amine) was synthesized and characterized by elemental analysis, single crystal X-ray diffraction and thermogravimetric analyses. X-ray structural analyses revealed that the crystal was monoclinic, space group P2(1)/c with lattice parameters a = 14.695(3) Å, b = 6.975(2) Å, c = 18.807(3) Å, β = 126.603(1)°, Z = 4, D c = 1.888 g cm?3, and F(000) = 892. The complex exhibits a 3D supermolecular structure which is built up from 1D zigzag chains. The enthalpy change of the reaction of formation for the complex was determined by an RD496–III microcalorimeter at 25 °C with the value of ?47.905 ± 0.021 kJ mol?1. In addition, the thermodynamics of the reaction of formation of the complex was investigated and the fundamental parameters k, E, n, \( \Updelta S_{ \ne }^{{{\uptheta}}} \), \( \Updelta H_{ \ne }^{{{\uptheta}}} \), and \( \Updelta G_{ \ne }^{{{\uptheta}}} \) were obtained. The effects of the complex on the thermal decomposition behaviors of the main component of solid propellant (HMX and RDX) indicated that the complex possessed good performance for HMX and RDX.  相似文献   

7.
A new cadmium coordination polymer [Cd(L)(Cl)(H2O)]n (1) (L = 5-(imidazol-1-yl)-2-pyridine carboxylic anion) constructed from dinuclear cadmium clusters has been synthesized under hydrothermal condition and structurally characterized by single-crystal X-ray diffraction analysis. The compound crystallizes in triclinic system, space group P-1, with a = 6.8747(6), b = 9.7434(8), c = 9.9119(7) Å, α = 118.615(8)°, β = 104.445(7)°, γ = 94.815(7)°, V = 548.01(9) Å3, Z = 2. Compound 1 is a one-dimensional (1D) double chain structure based on dinuclear [Cd2(Cl)2] clusters, and is further extended to a 3D supramolecular framework by hydrogen bonds. As a Lewis acid catalyst, compound 1 exhibits excellent catalytic performance for the acetalization reaction under mild conditions and can be reused several times without a significant decrease of the catalytic activity.  相似文献   

8.
A new sandwich polyoxometalate Na4Zn2[Zn2(H2O)10(ZnCl)6(B-α- BiW9O33)2] · 40.5H2O (1) has been obtained in aqueous solution and characterized by IR, UV, element analysis, TG and single-crystal X-ray analysis. Polyoxoanion 1 is composed of a Zn 6 12+ hexagon sandwiched by two [BiW9O33]9? units, which is firstly observed in tungstobismutate. The crystal data for compound 1: Triclinic, space group P–1, a = 15.426(3) Å, b = 15.467(3) Å, c = 15.526(3) Å, α = 74.24(3)°, β = 64.37(3)°, γ = 60.73(3)°, V = 2905.3(1) Å3, Z = 1.  相似文献   

9.
Reaction of copper(II) perchlorate with N,N′-{bis(pyridin-2-yl)benzylidene}butane-1,4-diamine (bpbd) yielded monoclinic crystals of bluish green [Cu(bpbd)(ClO4)]ClO4 (1), and a similar reaction in presence of azide anion, N3 ? formed monoclinic crystals of dark green [Cu(bpbd)(N3)]2ClO4 (2). Crystal data for 1: space group P21/c, Z=4, a=17.3968(4) Å, b=9.3182(2) Å, c=17.6794(4) Å, β=102.149(1)°. The geometry around Cu(II) centre is distorted square pyramidal with axial site occupied by O atom of perchlorate and in plane Cu is bonded to four N atoms of the organic ligand. The intermolecular C–H...π stacking in 1 forms a zigzag chain (1D) supramer. Crystal data for 2: space group C2/c, Z=4, a=22.3109(4) Å, b=17.7832(3) Å, c=14.3389(2) Å, β=92.553(1)°. In dinuclear 2, Cu(II) has tetragonally distorted octahedral geometry coordinated by four N atoms of bpbd, with the fifth and sixth positions occupied by N atoms of two end-on bridging azides. The π...π interaction leads to a two dimensional (2D) sheet within which the counter anions are embedded. Both the compounds 1 and 2 show simple paramagnetism. Cyclic voltammetry and fluorescence spectra are also reported.  相似文献   

10.
The first inorg/organic hybrid complex incorporating the macrocyclic oxamide, of formula [(NiL)2Cu2(μ-NSC)2(NSC)2] (1), (NiL, H2L = 2, 3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien), have been synthesized and structurally characterized. The crystals crystallize in the triclinic system, space group P-1, for (1) a = 8.319(3) Å, b = 10.434(4) Å, c = 14.166(5) Å, a = 107.030(5)°, β  =  91.257(5)°, γ = 107.623(5)°. The complex involved both bridging N, S-ligand, and oxamide ligand, C–H?S interactions and NCS → Ni weak coordination interactions making the complex superamolecular.  相似文献   

11.
A new three-dimensional platinum(II)–thallium(I) coordination polymer [{Pt(pda)(NHCOtBu)2}4Tl4][Pt(CN)4]2·2H 2 O (pda = 1,2-propyldiamine) has been prepared from the direct reaction of [Tl2Pt(CN)4] and [Pt(pda)(NHCOtBu)2] in water, and its structure was characterized by X-ray diffraction analysis. The compound crystallizes in monoclinic, space group Pn, a = 11.567(2) Å, b = 11.570(2) Å, c = 37.677(8)Å, β = 94.64(3)°, V = 5025.8(17) Å3, Z = 2, R1 = 0.0679 and wR2 = 0.1574 [I >  2σ (I)], Goodness-of-fit on F 2 = 1.055. The compound exhibits a novel 3D network structure consisting of [Pt(CN)4]2? connected 1D infinite Pt–Tl–Pt–Tl chains via strong Pt–Tl bonds.  相似文献   

12.
Potassium hydrogen bis-dichloroacetate (1) was synthesized and separated as crystals. Differential scanning calorimetry (DSC) measurement reveals that this compound undergoes a reversible phase transition at about 259 K with a heat hysteresis of 23.5 K. Dielectric anomaly observed at 260 K in the heating process further confirms the phase transition. The room temperature X-ray single-crystal structure determination indicates that 1 crystallizes in the monoclinic crystal system with a centrosymmetric space group P21/c, and cell parameters are a =?6.240(1), b =?23.177(4), c =?7.335(1) Å, β =?106.938(1)°, V =?1014.8(3) Å3, and Z =?4. In the low temperature phase, 1 also crystallizes in monolinic with space group P21/c, and cell parameters are a =?6.180(1), b =?22.988(2), c =?7.200(1) Å, β =?108.098(1)°, V =?972.4(1) Å3, and Z =?4. The structural phase transition is dominating caused by the torsion of bond angles.  相似文献   

13.
A novel 1-benzhydryl piperazine derivative 1-benzhydryl-4-(2-nitro-benzenesulfonyl)-piperazine was synthesized by the nucleophilic substitution of 1-benzhydryl piperazine with 2-nitro-benzenesulfonyl chloride. The product obtained was characterized spectroscopically and finally confirmed by X-ray diffraction study. The title compound, C23H23N3O4S crystallizes in the monoclinic space group C2/c with cell parameters a = 13.1120(9) Å, b = 21.4990(9) Å, c = 16.655(1) Å, β = 111.352(2)°, Z = 8, and V = 4372.7(4) Å. The structure reveals that the piperazine ring is in a chair conformation. The geometry around the S atom is distorted tetrahedral. There is a large discrepancy in the bond angles around the piperazine N atoms. The structure is stablized by C–H···O type intermolecular hydrogen bonding interactions.  相似文献   

14.
Schizophrenia is a debilitating mental disorder which affects approximately 1% of the world’s population. Clozapine is an atypical antipsychotic showing unmatched effectiveness in the control of treatment-resistant schizophrenia. Unlike typical antipsychotics, clozapine does not induce extrapyramidal side effects (EPS), tardive dyskinesia or elevate prolactin levels. However, clozapine can induce a potentially fatal blood disorder, agranulocytosis, in 1–2% of patients, severely limiting its clinical use. The model for antipsychotic activity under investigation is based on obtaining a clozapine-like profile with preferential dopamine D4 and serotonin 5-HT2A receptor affinity. Profiled herein are three unique members of a series of prospective antipsychotic agents. Compound (I) originated from the structural hybridization of the commercial therapeutics, clozapine and haloperidol, whilst compounds (II) and (III) possess an alternative tricyclic nucleus derived from JL13; a clozapine-like atypical antipsychotic developed by Liégeois et al. These compounds have been synthesized and characterized by means of elemental analysis, IR, 1H and 13C-NMR spectroscopy, MS and X-ray diffraction. Compound (I) crystallizes in space group P(?1) with a = 10.5032(1), b = 10.6261(2), c = 12.6214(3) Å, α = 81.432(1)°, β = 83.292(1)°, γ = 61.604(1)°, Z = 2, V = 1223.62(4) Å3, C28H29ClN4O, M r = 473.00, D c = 1.284 Mg/m3, μ = 0.185 mm?1, F(000) = 500, R = 0.0506 and wR = 0.1304. Compound (II) crystallizes in the monoclinic space group P21/c with a = 10.8212(2), b = 9.3592(2), c = 22.9494(5) Å, β = 106.471(1)°, Z = 4, V = 2228.88(8) Å3, C25H25ClN4O2, M r = 448.94, D c = 1.338 Mg/m3, μ = 0.202 mm?1, F(000) = 944, R = 0.0529 and wR = 0.1129. Compound (III) crystallizes in the monoclinic space group P21/c with a = 10.5174(2), b = 9.3112(2), c = 24.2949(5) Å, β = 98.666(1)°, Z = 4, V = 2352.03(8) Å3, C25H24Cl2N4O2, M r = 483.38, D c = 1.365 Mg/m3, μ = 0.306 mm?1, F(000) = 1008, R = 0.0478 and wR = 0.1067. The solid state conformations of (I), (II) and (III) exhibit the characteristic V-shaped buckled nature of the respective dibenzodiazepine and pyridobenzoxazepine nuclei with the central seven-membered heterocycle in a boat conformation. The molecules of (I) form a head-to-tail dimeric motif stabilized by hydrogen bonding. The results of a conformational analysis of compounds (I)–(III) investigating the effect of environment (in vacuo and aqueous solution) are presented. These analogues were tested for in vitro affinity for the dopamine D4 and serotonin 5-HT2A receptors and their comparative receptor binding profiles to clozapine and JL13 are reported.  相似文献   

15.
2-Propylamino-5-[4-(2-hydroxy-3,5-dichlorobenzylideneamino) phenyl]-1,3,4-thiadiazole, formulated as C18H16Cl2N4OS (I), was synthesized. The crystal and molecular structure of (I) have been determined by 1H-NMR, IR, and X-ray single crystal diffraction. The compound (I) crystallizes in the monoclinic, space group P2(1)/c with unit cell parameters a = 9.0576(2) Å, b = 24.3382(8) Å, c = 9.0585(2) Å, M r = 407.31, V = 1851.13(9) Å3, Z = 4, R 1 = 0.036, and wR 2 = 0.096. Molecular geometry from X-ray experiment of (I) in the ground state has been compared using the density functional method (B3LYP) with 6-31G(d) basis set. To determine conformational flexibility, molecular energy profile of (I) was obtained by semi-empirical (PM3) calculations with respect to selected degree of torsional freedom, which was varied from ?180° to +180° in steps of 10°. The results are indicative that the Schiff base, which contains a thiadiazole ring, prefers to be in E-configuration. In addition, molecular electrostatic potential, frontier molecular orbitals, and natural bond orbitals analysis were performed by the B3LYP/6-31G(d) method.  相似文献   

16.
An organic–inorganic hybrid material based on paradodecatungstate building blocks and sodium–aminoacetic acid complex subunits,{Na10(H3N–CH2–COO)2[H2W12O42]}·28H2O (1), have been synthesized under mildly acidic conditions. This compound was characterized by single-crystal X-ray diffraction, elemental analysis, IR and UV–visible spectroscopies, and cyclic voltammetry. The compound crystallizes in the triclinic space group P-1 with a = 11.879(2) Å, b = 12.706(2) Å, c = 13.067(2) Å, α = 74.11(3)°, β = 79.71(3)°, γ = 65.95(3)°, V = 1727.2(5) Å3, and Z = 1. The crystal structure consists of infinite 2D layers constructed from [H2W12O42]10? clusters and sodium–aminoacetic acid complexes; adjacent layers are further joined by the complex units and sodium cations to yield a three-dimensional network.  相似文献   

17.
S-allyl-β-N-[(2-hydroxyphenyl)methylene]hyrazinecarbodithioate) (1, H2L), the Schiff base of dithiocarbazate with unsaturated allyl substitution, can act as a new tridentate SNO ligand H2–L and react with cobalt(II) nitrate hexahydrate to form the novel linear trinuclear isovalence Co(II) complex, [Co3(H–L)2(L)2] 2C2H5OH (2). The compounds were characterized by elemental analysis, infrared, and ultraviolet spectroscopy. Compound 2 was also characterized by single-crystal X-ray analysis and crystallizes in the orthorhombic space group, Pbcn, with a = 30.643(1) Å, b = 9.118(4) Å, c = 19.017(7) Å, α = β γ = 90°, V = 5312.95 Å3, Z = 4, and R 1 = 0.0790, (wR 2) = 0.1223. The six-coordinate central Co(II) atom is bonded to two deprotonated metal-containing ligands. The terminal Co(II) atoms are in a square planar SNON four-coordinate environment and connected to the central Co(II) by N-atoms from the ligand backbone. For quantifying the intermolecular interactions in crystal lattice, the new d norm surface and the breakdown of fingerprint plots have been used for visualizing and exploring the compound 2.  相似文献   

18.
Two new one-dimensional chain-like compounds, K4Na4[Mn2(H2O)8Mn4(H2O)2(GeW9O34)2] · 20.5H2O (1) and K2Na4Cu2(H2O)12[Cu(H2O)2Cu4(H2O)2(SiW9O34)2] · 15H2O (2), constructed from the sandwich-type clusters, have been obtained by the routine synthetic reactions in aqueous solutions, and their structures were determined by X-ray single crystal diffraction analysis. The crystal data is following: for 1, space group, monoclinic, P 21/n, a = 16.693(3) Å, b = 14.935(3) Å, c = 20.090(4) Å, β = 92.23(3)°, V = 5004.7(17) Å3, Z = 2; For 2, space group, triclinic, P ?1, a = 11.744(2) Å, b = 13.415(3) Å, c = 17.609(4) Å, α = 73.08(3)°, β = 82.68(3)°, γ = 65.18(3)°, V = 2409.1(8) Å3, Z = 1. The crystal structure of 1 shows a 1D ladder-like chain, built up of the sandwich anions [Mn4(H2O)2(GeW9O34)2]12? and the Mn2+ ions. Compound 2 is a polymeric chain, composed of the Cu-substituted sandwich-type anions [Cu4(H2O)2(SiW9O34)2]12? linked by the Cu(H2O)4 clusters. These extended materials based on the sandwich-type polyoxoanions are rarely reported in the POM chemistry.  相似文献   

19.
The title compound {Cu[S2P(OC2H5)2](bpe)} n (1) is constructed from flexible ligand bpe (bpe = 1,2-bis(4-pyridyl)ethane) and the Cu[S2P(OC2H5)2], which was characterized by single crystal structure determination, elemental analysis, XRD, and IR spectra. X-ray diffraction studies revealed that polymeric compound 1 consists of dinuclear module to form 1-D chains with the intramolecular Cu···Cu interactions (ca. 2.63 Å). This interaction may show a profound influence on the observed blue luminescence emission spectrum for 1. Crystal data for 1 at 293(2) K: Space group P ? 1, a = 9.277(3), b = 10.504 (4), c = 31.801(1) Å, α = 92.849(3), β = 90.401(2), γ = 114.547(7)°, V = 2813.9(2) Å3, Z = 2, R 1 = 0.041.  相似文献   

20.
A novel bis-heterocyclic compound was synthesized and characterized. The crystal structure of the title compound (C22H20ClN5OS, Mr = 437.94) has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P-1 with a = 8.646 (2), b = 9.148 (3), c = 14.540 (4) Å, α = 94.422 (4), β = 98.500 (4), γ = 102.823 (4)°, V = 1101.8 (5) Å3, Z = 2, F(000) = 312, Dc = 1.320 g/cm3, μ = 0.2900 mm?1, the final R 1 = 0.041000 and wR 2 = 0.1160 for 2675 observed reflections with I > 2σ(I). A total of 5623 reflections were collected, of which 3866 were independent (R int = 0.019000). The fungicidal activity of title compound was determined, the results showed the title compound displayed moderate fungicidal activity against G. zeae Petch, Phytophthora infestans (Mont.) de Bary, Botryosphaeria berengeriana f. sp. piricola (Nose) koganezawa et Sakuma, Fusarium oxysporum f.sp. cucumerinum, and Cercospora arachidicola.  相似文献   

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