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1.
The molecular and crystal structures of the title compound, C16H18N2O, were characterized and determined by single crystal X-ray diffraction method in addition to spectroscopic means such as IR, UV–VIS and 1H NMR. The compound crystallizes in orthorhombic space group P bca, with a = 9.3350(5) Å, b = 23.4878(13) Å, c = 26.5871(12) Å, Z = 16, D calc. = 1.1591(1) g/cm3, μ (MoKα) = 0.073 mm?1. Monomers of the compound in the crystal structure are linked into C(7) and C(8) chains generated by translation along the [1 0 0] direction with the aid of O–H···N type H-bonds which serve to the stabilization of periodic organization of the molecules beside major and minor component in the disordered azo fragment. In order to describe conformational flexibility and the crystal packing effects on the molecular conformation, potential barriers regarding the rotation along both Ar–N bonds were calculated by varying the related torsional degrees of freedom in every 10° ranging from ?180° to +180° via quantum chemical calculations at DFT/B3LYP level.  相似文献   

2.
Trans-Bis[1,3-bis(2,4-dimethylphenylimidazolidin-2-ylidene)]dichloropalladium(II), 4, was prepared from 1,3-bis(2,4-dimetilphenyl)imidazoliniumchloride. The crystal and molecular structure of 4 have been determined by single crystal X-ray diffraction. The title compound, C38H44N4PdCl2, crystalizes in the monoclinic space group P 21/n with a = 13.8713(9) Å, b = 12.1365(6) Å, c = 21.5499(15) Å. The Pd atom has a slightly distorted square planar coordination geometry. The molecules of the title compound are linked by C–H···Cl weak hydrogen bonds into two-dimensional sheets parallel to the (001) plane. In addition, the title compound was characterized by elemental analyses and NMR spectroscopy.  相似文献   

3.
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   

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.
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   

6.
A novel cyclopropane derivative, 1-cyano-N-p-tolylcyclopropanecarboxamide (C12H12N2O, Mr = 200.24) was synthesized and its structure was studied by X-ray diffraction, FTIR, 1H and 13C NMR spectrum and MS. The crystals are monoclinic, space group P2_1/c with a = 7.109 (4), b = 13.758 (7), c = 11.505 (6) Å, α = 90.00, β = 102.731 (8), γ = 90.00 °, V = 1097.6 (9) Å3, Z = 4, F(000) = 312, D c  = 1.212 g/cm3, μ = 0.0800 mm?1, the final R = 0.0490 and wR = 0.1480 for 1,375 observed reflections with I > 2σ(I). A total of 6,109 reflections were collected, of which 2,290 were independent (R int = 0.0290). Theoretical calculation of the title compound was carried out with HF/6-31G (d,p), B3LYP/6-31G (d,p), MP2/6-31G (d,p). The full geometry optimization was carried out using 6-31G(d,p) basis set, and the frontier orbital energy. Atomic net charges were discussed, and the structure-activity relationship was also studied. The preliminary biological test showed that the synthesized compound is bioactive against the KARI of Escherichia coli.  相似文献   

7.
The structures of tris-hexafluoroacetylacetonates Al(hfa)3 and Sc(hfa)3·H2O are determined by single crystal X-ray crystallography (Bruker-Nonius X8 Apex diffractometer, MoK α radiation, T = 150(2) K). The Al(hfa)3 complex is trigonal, a = 17.8944(11) Å, c = 12.4061(11) Å, P-3c1 space group, V = 3440.3(4) Å3, Z = 6, R = 0.076. The Sc(hfa)3·H2O complex is monoclinic, a = 16.0926(4) Å, b = 14.7980(3) Å, c = 24.4020(5) Å, β = 125.641(1)°, P21/c space group, V = 4722.54(18) Å3, Z = 8, R = 0.060. The structures of the complexes are formed by neutral molecules; the coordination environment of the metal atom involves six oxygen atoms of three β-diketone ligands (Al(hfa)3) and, additionally, a water oxygen atom (Sc(hfa)3·H2O). The shortest Al...Al distance is 6.203(6) Å. The Sc(hfa)3·H2O molecules are joined in dimers by hydrogen bonds with Sc...Sc separations of 5.6992(8) Å and 5.6853(8) Å. In the crystals, the molecules are joined by van der Waals interactions, moreover, there are intermolecular contacts F...H ~ 2.5 Å in the structure of Sc(hfa)3·H2O.  相似文献   

8.
The structure and the EPR spectra of copper(II) coordination compounds with acyldihydrazones of N-benzenesulfonyl-L-aspartic acid and salicylaldehyde (2-hydroxyacetophenone) were described. The compounds were studied by chemical and thermal analyses, IR spectroscopy, and EPR. The molecular and crystal structures of copper(II) complexes with N-benzenesulfonyl-L-aspartic acid bis(salicylidene)hydrazone (H4L1) [Cu2L1 · 2Py] · 1.5 H2O was determined by X-ray diffraction. The crystals are triclinic: a = 10.4714(4) Å, b = 12.9702(5) Å, c = 14.6187(9) Å, α = 104.763(2)°, β = 93.082(2)°, γ = 111.4240(10)°, space group P \(\bar 1\), Z = 2. The binuclear complexes containing copper cations whose coordination polyhedra are connected by an aliphatic spacer (Cu...Cu, 8.669 Å) are additionally linked by phenoxy bridges (Cu...Cu, 3.398 Å). The EPR spectra of these compounds in solutions exhibit an isotropic signal of seven HFS lines due to two equivalent copper ions with the spin Hamiltonian parameters g = 2.115?2.120, a Cu = (35.5?38.0) × 10?4 cm?1, which is indicative of weak exchange interactions between the paramagnetic sites.  相似文献   

9.
Reactions of acetamide with platinum(II) diamines [Pt(N,N-DimeEn)Cl2], [Pt(Tm)Cl2], and [Pt(N,N-DimeTm)Cl2] (N,N-DimeEn = (CH3)2N(CH2)2NH2, Tm = NH2(CH2)3NH2, N,N-DimeTm = (CH3)2N(CH2)3NH2) with preliminary precipitation of chlorine ions by silver salts gave binuclear Pt(II) acetamidates [Pt2(CH3)2N(CH2)2NH2)2(μ-NHCOCH3)2](NO3)2 · H2O (I), [Pt2(NH2(CH2)3NH2)2)(μ-NHCOCH3)2](NO3)2 · H2O (II), and [Pt2(CH3)2N(CH2)3NH2)2(μ-NHCOCH3)2](HSO4)2 (III), whose crystal structures were determined. Crystals of I are monoclinic: a = 14.459(2) Å, b = 17.197(3) Å, c = 9.822(2) Å, β = 105.923(10)°, V = 3348.6(8) Å3, space group P2(1)/c, Z = 4, R hkl = 0.0419 for 6663 reflections. Complex I is a binuclear acetamidate with bridging (NHCOCH3)? ligands, one of which is bound to two Pt atoms through the N and O atoms, and the other ligand is bound only through the N atom. The Pt-Pt distance is 2.987(1) Å. Crystals of II are monoclinic: a = 10.213(7) Å, b = 13.373(9) Å, c = 16.533(11) Å, β = 97.971(9)°, V = 2236(3) Å3, space group P2(1)/n, Z = 4, R hkl = 0.557 for 6462 reflections. The Pt-Pt distance is 3.057(1) Å. Crystals of III are monoclinic: a = 10.557(12) Å, b = 18.531(2) Å, c = 14.4744(17) Å, β = 108.705(2)°, V = 2682(5) Å3, space group P2(1)/n, Z = 4, R hkl = 0.569 for 8506 reflections. The Pt-Pt distance is 3.202(1) Å. Complexes II and III are binuclear acetamidates, in which two chelating Pt(Tm) or Pt(N,N-DimeTm) moieties are coordinated through the N and O atoms of (NHCOCH3)? cis-bridges.  相似文献   

10.
The structure of 1,8-bis(fluoroboro)-2,7,9,14,15,20-hexaoxa-3,6,10,13,16,19-hexaaza-4,5,11,12-tetraphenyl-17,18-bisc(tert-butylamino)-bicyclo[6.6.6]eicosa-3,5,10,12,16,18-hexaene(2−)iron(2+) tris-dioximate clathrochelate was determined by X-ray diffraction (XRD) analysis. The compound has a molecular structure and crystallizes as triclinic crystals: a = 10.7673(2) Å, b = 11.9520(4) Å, c = 22.5473(7) Å, α = 75.729(1)°, β = 89.161(1)°, γ = 65.334(1)°, V = 2542.64(13) Å3, Z = 2, space group 1. P1ˉ. Original Russian Text Copyright ? 2007 by A. B. Burdukov, N. V. Pervukhina, M. A. Vershinin, and Ya. Z. Voloshin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 48, No. 2, pp. 366–369, March–April, 2007.  相似文献   

11.
l-Tyrosine alkyl esters are used as prodrugs for l-tyrosine. Although prodrugs are often designed for their behavior in solution, understanding their solid-state properties is the first step in mastering drug delivery. The crystal structure of l-tyrosine methyl ester has been determined and compared to published structures of l-tyrosine and its ethyl and n-butyl esters. It is almost isostructural with the other esters: it crystallizes in the orthorhombic chiral space group P212121, a = 5.7634(15) Å, b = 12.111(2) Å, c = 14.3713(19) Å, V = 1003.1(4) Å3 with Z′ = 1. Their main packing motif is a C(9) infinite hydrogen-bond chain, but the conformation of l-tyrosine methyl ester is different from the other two: eclipsed versus U-shaped, respectively. The published structure of the ethyl ester, which was incomplete, has been confirmed by X-ray powder diffraction data. Because l-tyrosine methyl ester is very stable (28 years stored at room temperature), and its hydrolysis rate is relatively low, it should be one of the better prodrugs among the alkyl esters of tyrosine.  相似文献   

12.
X-ray structural analysis has been performed for two complex compounds: Cu(en)2(o-HB)2H2O (I) (a = 16.873(4) Å, b = 8.713(2) Å, c = 14.803(3) Å, β = 91.15(2)°, V = 2175.8(8) Å3, C2/c, Z = 4, R(F) = 0.0263, 1516 reflections with I > 3σ (I)) and [Cu(en)2(OH2)2]2+(o-AB?)2 (II) (a = 7.488(5) Å, b = 22.122(8) Å, c = 7.856(5) Å, β = 118.77(2)°, V = 1140.7(11) Å3, P21/n, Z = 2, R(F) = 0.0432, 1684 reflections with I > 3σ(I)) synthesized under identical conditions (en is ethylenediamine, o-HB is o-hydroxybenzoate, and o-AB is o-aminobenzoate). Although the compounds were assumed to have similar structures and the Cu-Lig bond lengths and the cis and trans angles are acceptable for an octahedral structure, the geometric parameters of o-HB suggest that the copper atom has a plane square environment.  相似文献   

13.
1-Methyl-1H-tetrazoline-5-thione (1) reacts with iodine in CHCl3 with formation of 1:1 stable σ-complex (logβ = 3.8 ± 0.1 is found by spectrophotometry). In the ethanol solution irreversible oxidation with formation of disulfide product 5,5′-dithiobis(1-methyl-1H-tetrazole) (2) is observed. The structure of (2) was determined by X-ray diffraction. Strong intermolecular interactions with shortened contacts are observed between sulfur atom of disulfide bridge and heterocyclic nitrogen of the neighboring molecule (S···N 3.0179(15) Å) forming infinite supramolecular chains which are further linked with π–π stacking interaction of tetrazole rings (interplane distance is 3.1685(6) Å).  相似文献   

14.
The crystal structure of an antimony(III) fluoride complex of the composition (C5H12NO2)SbF4·H2O (I) involving a cation of α-amino isovaleric acid (DL-valine, Val) is determined. Crystals are monoclinic: a = 12.2024(2) Å, b = 6.1636(1) Å, c = 15.5167(3) Å, Z = 4, space group P21/c. The structure is formed of DL-valinium (C5H12NO2)+ cations, complex [SbF4]nn? anions having a polymeric chain structure, and crystallization water molecules. The [SbF4]nn? complex anions consist of trigonal SbF4E bipyramids joined together by asymmetric bridging Sb–F(3)···Sb bonds. The structural units are organized into a threedimensional framework via N–H···F, N–H···O, and O–H···F hydrogen bonds.  相似文献   

15.
Synthesis and results of the single crystal X-ray diffraction study of iron(III) pivaloyltrifluoroacetonate are reported. Crystal data for C24H30FeF9O6: a = 9.2205(6) Å, b = 9.6584(10) Å, c = 17.3799(17) Å, α = 75.902(2)°, β = 80.517(3)°, γ = 82.746(3)°, space group P-1, V = 1474.6(2) Å3, Z = 2. The structure is molecular with the octahedral environment of Fe atom, Fe-Oav 1.991 Å, ∠O-Fe-Oav 86.48°. The van der Waals energy of intermolecular interactions is calculated and compared to thermodynamic data.  相似文献   

16.
The complex [(CH3)2NC(NH2)NHC(NH2)NH2]SiF6 (I) was synthesized and its structure was determined by X-ray crystallography. The crystals are monoclinic: a = 7.4346(10) Å, b = 12.7628(10) Å, c = 11.0828(10) Å, β 104.080(10)°, V = 1020.01(18) Å3, ρcalc = 1.780 g/cm3, μ(MoK α) = 0.302 mm?1, Z = 4, space group P21/c. The crystals of I are composed of SiF 6 2? anions (Si-F, 1.657(2)–1.699(2) Å) and N,N-dimethylbiguanidinium (H2L2+) cations combined in a framework by interionic H-bonds NH···F. In the cations, protonation sites are the terminal imide groups.  相似文献   

17.
The crystal structures of the compounds trans-[Rh(en)2Cl2]Cl2 · H5O2 (I), trans-[Rh(en)2Cl2]ClO4 (II), and trans-[Rh(en)2Cl2]ReO4 (III) are determined. The crystal data are: I, a = 10.860(3) Å, b = 7.795(2) Å, c = 9.023(3) Å; β = 111.56(10)°, P21/c space group, Z = 4, d x = 1.875 g/cm3; II, a = 6.593(2) Å, b = 8.309(3) Å, c = 11.922(4) Å, α = 83.55(10)°, β = 79.80(10)°, γ = 75.38(10)°, P \(\bar 1\) space group, Z = 2, d x = 2.106 g/cm3; III, a = 6.533(2) Å, b = 16.391(4) Å, c = 12.411(3) Å; β = 98.30(10)°, P21/c space group, Z = 4, d x = 2.749 g/cm3. The compounds are examined by IR spectroscopy and powder XRD. The solubility of the isolated crystalline phases in water decreases in the following order: trans-[Rh(en)2Cl2]Cl2·H5O2 > trans-[Rh(en)2Cl2]ClO4 > trans-[Rh(en)2Cl2]ReO4.  相似文献   

18.
For 4,7,13,16,21,24-hexaoxa-1,10-diazoniabicyclo[8.8.8]hexacosane bis(picrate) hydrate [H2(Crypt-222)]2+·2Pic?·1.19 H2O (I), its disordered crystal structure has been determined by X-ray diffraction (XRD) analysis. The structure of I (space group \(P\bar 1\), a = 10.662 Å, b = 12.586 Å, c = 15.342 Å, α = 107.73°, β = 102.33°, γ = 90.49°, Z = 2) was solved by direct methods and refined by full-matrix least-squares in an anisotropic approximation to R = 0.111 for all 5000 independent reflections collected (CAD-4 automatic diffractometer, CAD-4, λMoKα). The 2.2.2-cryptand dication is disordered and has two different conformations with probabilities of 66.7% and 33.7%. In addition to one independent water molecule, the cavity of the dication has a low-probability site of another water molecule, whose occupancy is 0.19. In the two independent picrate anions, some of their NO2 groups are disordered over two orientations. The crystal structure of I has various interionic (intermolecular) and intracation hydrogen bonds.  相似文献   

19.
trans-Bis-(4-phenyliminopentan-2-onato)Cu(II) (5), which is a phenyl-substituted ketoimine, was synthesized, and an X-ray study was performed for this compound. Crystal data for CuN2O2C22H24: a = 11.4557(3) Å, b = 26.6845(9) Å, c = 14.2976(5) Å, β = 113.2270(10)°; space group P21/n, Z = 8, d calc = 1.363 g/cm3, R = 0.033. The structure is molecular and built of isolated trans complexes. The central copper atom is surrounded by four atoms (2O+2N) with the average distances Cu-O 1.904(3) Å and Cu-N 1.962(3) Å. The polyhedron around the copper atom is a distorted tetrahedron; the average values of the O-Cu-O and N-Cu-N trans bond angles are 147(2)° and 150(2)°, respectively. The average value of the O-Cu-N angles is 94(1)°.  相似文献   

20.
Two ethylenediamine derivatives—N-(2-ammoniumethyl)carbamate HN(COO?)CH2CH2N+H3 (I) and tetraacetylethylenediamine (H3CC(O))2NCH2CH2N(C(O)CH3)2 (II) (synthesized for the first time)—have been synthesized and characterized by X-ray crystallography. Compounds I and II are isolated as minor admixtures upon an attempt to synthesize ethylenediamine complexes of lanthanum and neodymium nitrates, respectively. The crystals of I and II are monoclinic: a = 7.778 Å, b = 8.060 Å, c = 7.568 Å, β = 95.73°, Z = 4, space group P21/c (I); a = 5.946, b = 10.255, c = 9.343 Å, β = 95.72°, Z = 2, space group P21/c (II). The bond lengths and bond angles lie within the corresponding standard values. Compounds I and II have different conformations of the N-C-C-N ethylenediamine moiety: gauche in I and trans in II, and the corresponding torsion angles are equal to 66.6° and 180°, respectively.  相似文献   

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