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1.
The synthesis, crystal structure analysis and characterization of a monoazo dye, 4-((2,6-dichloro-4-nitro phenyl)azo)-N-(diacetyl oxygen ethyl)aniline, are reported. The dye crystallised in the triclinic system, space group P-1 with a=8.1663(3) Å, b= 9.4222(3) Å, c=15.4694(5) Å, α=78.9130(10)°, β=75.019(2)°, γ=70.787(2)°, V=1078.26(6) Å3 and Z=2. There is only one molecule in the asymmetric unit. The dihedral angle between the two phenyl rings is 53.4 Å. In the crystal structure, intermolecular C-H…O hydrogen bonds link the molecules into centrosymmetric dimers, forming R22(30) ring motifs, in which they may be effective in the stabilization of the structure. Between the phenyl rings, the ππ stacking (interactions) may further stabilize the structure.  相似文献   

2.
Catena-poly[fac-triiodobismuth(III)-tris-(µ-ethane-1,2-diylbis(diphenylphosphane oxide-κ2O,O′))], a 2-D sheet network of BiI3 was synthesized from BiI3 and ethane-1,2-diylbis(diphenylphosphane oxide) (DppeO2) in tetrahydrofuran. The crystal structure revealed a trigonal structure with three-fold symmetry at Bi. Bismuth centers show fac-BiI3O3 coordination, with Bi–I?=?2.9416(2) Å and Bi–O?=?2.4583(17) Å. The I–Bi–I and O–Bi–O angles (95.520(7)° and 79.04(6)°, respectively) indicate trigonal distortion in the Bi octahedron. Bridging DppeO2 ligands centered on inversion centers give rise to a 2-D sheet polymer. The 8.3 Å thick sheets consist of three layers in a sandwich structure. The outer layers are composed of phenyl rings and BiI3 groups with the iodide atoms pointing outward. The central layer consists of the O=PCH2CH2P=O bridging groups. Computational results suggest that semi-conducting behavior arises from Bi(III) centers. A halide to DppeO2 π* transition is suggested by theoretical results.  相似文献   

3.
The thiourea derivative 1-(2-Furoyl)-3-phenylthiourea (FPT) was synthesized and characterized by using spectroscopic (IR, Raman, UV–VIS, 1H and 13C NMR) and structural methods (powder X-ray diffraction data). The experimental measurements were complemented with quantum chemical calculations. FPT crystallizes in the monoclinic crystal system, space group P21/c, with cell parameters a?=?4.7679(5) Å, b?=?20.9704(2) Å, c?=?12.5109(5) Å and β?=?109.811(10)°, V?=?1176.87(3) Å3. In the crystal structure, the thiourea group makes dihedral angle of 43.8(5)° with the furoyl group, whereas the benzene ring is inclined by 24.3(4)°. The anti-syn geometry of the thiourea unit is stabilized by intramolecular N–H?…?O hydrogen bond between the H atom of the syn thioamide and the carbonyl O atom. In the crystal structure, molecules of FPT are packed through N–H···S, C–H···O and C–H···C hydrogen bonds, and a π–π interaction with offset arrangement. Hirshfeld surface analysis was performed in order to evaluate and quantify intermolecular interactions. The Hirshfeld surface analysis indicated that the H···H interactions comprise the majority of interactions. Shape index and curvedness clearly indicate π–π interactions in the compound FPT.  相似文献   

4.
The crystal structure and molecular conformation of 2,4,6-tricyano-4'-N,N-diethylaminoazobenzene (C19H16N6, mol. wt. 328.4a.m.u.) has been determined from X-ray diffraction data: monoclinic P21/c, a = 9.302(7)Å, b = 8.733(5)Å, c = 20.98(1) Å, β = 94.93(6)°, V = 1699(2)Å3, Z = 4, Dc = 1.284gem?3, F(000) = 688, λ(MoKα) = 0-71069Å, μ(MoKα) = 0.76cm?1. The structure was solved by MULTAN andrefined by full-matrix least-squares toR = 0.050 for 1358 independent observed reflections. The azobenzene skeleton is planar to within 0.12Å. Most significant bonding data are: NN, 1.286(4) Å; mean C-N (azo) 1.383(4) Å; mean C-C (cyano) 1.439(5) Å; mean CN 1.146(5)Å; NN-C, 112.8(2)° and 115.9(2)°; N-C-C (cis relative to NN) 127.6(2)° and 124.3(2)° ; N- C- C(trans) 115.2(2)° and 117.7(2)°.  相似文献   

5.
The crystal structure of ionic [NBu4][Bi(dmit)2] (5: Q=NBu4), obtained from BiBr3 and [NBu4]2[Zn(dmit)2], has been determined. The bismuth atoms are six coordinate, as a consequence of two inter-anion Bi–S contacts with two neighbouring anions. In addition to the four intra-anion Bi—S bonds to the two thiolato S atoms of the dmit ligands [Bi–S between 2.5872(14) and 2.8082(13) Å: the inter-anion bonds involve thione S atoms [Bi—S(10)i=3.2548(11) and Bi–S(10)ii 3.4628(13) Å]. Excluding consideration of any lone pair effect, the Bi atoms have very distorted octahedral geometries. The anions form centrosymmetric pairs of chains with the shortest Bi–Bi distance of 4.180 Å being between the pairs of chains; overlapping parallel dmit ligands, within the pairs of chains, are separated by a perpendicular distance of 3.477(2) Å, with the dmit centroid–dmit centroid separation of 3.529 Å, ideal for π–π interaction.  相似文献   

6.
The structure of 2,6-dichloro-4′-N,N-diethylaminoazobenzene has been determined from X-ray diffractometer data: C16H17Cl2N3, MW = 322·2, monoclinic, P21/n, a = 11·160 (2), b = 12·066 (2), c = 13·633 (3) Å, β = 116·46 (2)°, V = 1643·5 Å3, Z = 4, Dc = 1·30 g cm?3, F(000) = 672, λ(MoKα) = 0·71069 Å, μ(MoKα) = 3·94 cm?1. The structure was solved by direct methods and refined to R = 0·073 for 1495 independent reflexions. The molecule is non-planar with a dihedral angle of 87·8° between the phenyl rings. The effects of substituents on the aromatic ring geometry are discussed. Significant molecular parameters are: NN, 1·164 (9) Å; mean ClC, 1·741 (6) Å; mean CN(azo), 1·487 (9) Å; NNC, 112·4 (2)° and 109·1 (2)°; NCC (cis relative to NN), 125·5 (3)° and 122·4 (2)°; NCC (trans relative to NN) 114·0 (3)° and 119·5 (3)°; mean CC(Cl)C, 122·3 (3)°.  相似文献   

7.
A new 14-membered hexazamacrocyclic copper(II) complex [Cu(H2L1)](ClO4)4(L1=1,8-bis(2-aminoethyl)-1,3,6,8,10,13-hexaazacyclotetradecane) has been prepared by the one-pot reaction of ethylenediamine and formaldehyde in the presence of the Cu(II) ion. The crystal structure of [Cu(H2L1)](ClO4)4 was determined by X-ray diffraction. It crystallizes in the triclinic space group P−1 with a=12.118(2) Å, b=12.438(2) Å, c=12.466(2) Å, α=102.26(1)°, β=112.82(1)°, γ=111.51(1)°, and Z=2. The coordination geometry around the copper(II) ions is axially elongated octahedral with four nitrogen atoms of the macrocycle [Cu–N 2.012(7) Å for Cu(1) and 2.013(6) Å for Cu(2), average value] and two oxygen atoms of two ClO4 anions [Cu–O=2.550 Å for Cu(1) and 2.601(6) Å for Cu(2)]. [CuL2](ClO4)2(L2=3,7-bis(2-aminoethyl)-1,3,5,7-tetraazabicyclo[3,3,2]decane) with a novel tetraazabicyclic ligand was obtained from the same reaction system as an additional product. Crystal structure of [CuL2](ClO4)2: monoclinic space group Cc, a=16.393(3) Å, b=8.8640(18) Å, c= 13.085(3) Å, β=105.01(3)°, and Z=4.  相似文献   

8.
The crystal structure of 2-bromo-4-cyano-4′-N,N-diethylaminoazobenzene has been determined from X-ray diffraction data: C17H17N4Br, mol. wt = 357·1. Triclinic, Pī (No. 2), α = 13·162(5) Å, b = 7·516(3) Å, c = 8·496(4) Å, α = 101·63(4)°, β = 95·79(4)°, γ = 91·49(4)°, V = 818·10 Å3, Z = 2, Dc = 1·45 g cm?3, F(000) = 378, λ(MoKz) = 0·7107 Å, μ(Mo) = 26·70 cm?1. The structure was solved by direct methods and refined by full-matrix least-squares to R = 0·053 for 2081 independent reflexions. The molecule possesses an essentially planar azobenzene skeleton. The effects of substituents on the geometry of the azo group are discussed. Significant molecular parameters are: NN, 1·264(6) Å; 1BrC, 1·904(5) Å; mean NC, 1·410(7) Å; NNC, 115·7(2)° and 113·0(2)°; NCC (cis relative to NN), 125·4(3)° and 123·1(2)°; CC(Br)C, 123·0(2)°.  相似文献   

9.
The crystal structure and molecular conformation of 2-cyano-4-bromo-4′-N,N-diethylaminoazobenzene (C17H17N4Br, mol. wt. = 357·2 a.m.u) has been determined from X-ray diffraction data; triclinic, P1 (No. 2), a = 10·132(11) Å, b = 12·216(16) Å, c = 6·966(11) Å, α = 104·21(9)°, β = 92·67(12)°, γ = 97·22(7)°, V = 826·5(9) Å3, Z = 2, Dc = 1·436 g cm?3, F(000) = 378, λ(MoKα) = 0·71069 Å, μ(MoKα) = 26·0 cm?1. The structure was solved by the multiple solution direct method and refined by full-matrix least-squares to R = 0·059 for 1538 independent observed reflections. The azobenzene skeleton is planar to within 0·06 Å. Most significant bonding data are: NN, 1·290(8) Å; BrC, 1·866(6) Å; mean CN (azo) 1·380(8) Å; NNC, 113·6(4) and 115·3(4)°; NCC (cis relative to NN) 125·9(4)° and 126·7(4)°; NCC (trans) 116·8°(5)° and 116·1(4)°.  相似文献   

10.
trans-9,10-Dihydroxy-9,10-diphenyl-9,10-dihydroanthracene (2) and its 1:2 molecular complex (3) with methanol have been subjected to X-ray analysis. The crystal structure of 2 is built of discrete molecules held by π interactions between neighboring parallel phenyl rings and van der Waals forces, whereas that of 3 features virtually rhombic hydrogen-bonded (OH)4 rings, each comprising two methanol fragments and two hydroxy groups, linking the molecular moieties into a chain-and-layer arrangement. The molecular stereochemistry, hydrogen bonding, and packing modes in these two compounds are compared with those in the 1:1 adducts of 2 with ethanol and 1,4-butanediol. Crystal data: for 2, space group P1, a = 6.814(1), b = 8.119(1), c = 9.053(1)Å, α = 103.66(1), β = 96.30(1), γ = 106.55(1)°, and Z = 1 : for 3, space group C2/c, a = 12.165(3), b = 12.484(3), c = 16.349(4)Å, β = 110.33(2)° and Z = 4. Based on observed MoKα data, the structures of 2 and 3 have been refined to RF = 0.069 for 1139 reflections and RF = 0.070 for 1412 reflections, respectively.  相似文献   

11.
Stereochemical Investigations of Heterocyclic Compounds. XII. Structural Investigations of 1-(2-Amino-1-cyano-2-thio)ethene Pyridinium Ylides Two isomerization processes were found by 1H-d-n. m. r. characterized by ΔG* = 67 ± 4 KJ/mol for E- Z-isomerization and ΔG* = 46 ± 5 KJ/mol for the hindered rotation of the pyridine substituent in 1a . The structure of 1b was solved by direct method. Crystals are monoclinic space group P21/n, a = 13.682(3), b = 9.452(1), C = 19.713(6) Å, β = 96.42(2)°, V = 2533.3 Å3, Dx = 1.328 Mg · m−3, Z = 8. Both E- and Z-isomeres of 2b are found in the crystal lattice. The amino C distance with 1.369 (1,387) Å is shorter than the theoretical single bond distance. The formal  CC double bond with 1.377 (1.391) Å is considerably longer than 1.337 Å observed in the some alkenes.  相似文献   

12.
In a sequence of temperature-dependent solid-state reactions in the system CaO–Al2O3–MgO the formation of the ternary phase Ca3Al4MgO10 or C3A2M has been studied. Whereas the compound could not be prepared at 1200°C, a yield of 85 wt.-% of Ca3Al4MgO10 was obtained at 1320°C (incongruent melting point: 1330°C). Powder diffraction data compare well with results of previous investigations from the 1960s. Single crystals of Ca3Al4MgO10 could be retrieved from the sinter-pellets. Basic crystallographic data are as follows: orthorhombic symmetry, space group Pbcm, a = 5.14073(8), b = 16.7576(2), c = 10.70977(16) Å, V = 922.61(2) Å3, Z = 4. Using synchrotron diffraction data it was possible to solve the crystal structure. Least-squares refinements resulted in a residual of R(|F|) = 0.021 for 1000 independent observed reflections with I > 2σ(I) and 97 parameters. The structure contains [TO4]-tetrahedra (T=Al,Mg) forming a three-dimensional (3-D) framework whose topological characteristics have been determined. Al-Mg distributions on the different T-sites have been studied. The calcium cations are located in voids of the network. More than 50 years after its first observation our investigation clarifies the crystal structure of a compound belonging to a system that is of relevance for several fields of materials science.  相似文献   

13.
The synthesis and characterization of two tungsten carbonyl dimers containing bridging alkoxide or aryloxide ligands are described. The crystal and molecular structures of [PPN]2[W2(CO)8(OCH2CF3)2], 1, and [Et4N]3[W2(CO)6-(OPh)3]-CH3CN, 2 , are reported and compared with the structures of tetranuclear tungsten derivatives previously described. The dimer 1 crystalizes in the triclinic space group P 1 with unit cell parameters a = 13.460(11) Å, b = 12.318(5) Å, c = 13.842(10) Å, α = 82.73(5)°, β = 59.11(5)°, γ= 80.09(5)°, V = 1938(2) Å3, and Z = 1. The complex 2 crystalizes in the monoclinic space group P21/n with unit cell parameters a = 11.954(2) Å, b = 19.359(4) Å, c = 26.462(5) Å, β = 102.50(16)°, V = 5979(2) Å3, Z = 4. Molecular modeling software was utilized to construct a tetranuclear derivative from 1 similar to the structurally characterized [W(CO)3OH]4−4 tetramer. The two tetramers were found to possess similar molecular parameters. This supports the contention that dimers of type 1 are the precursors of the tetramers. Comparisons of the tungsten alkoxides and aryloxides with the behavior of W(CO)6 on γ-alumina are provided.  相似文献   

14.
A new compound, CdPb2O2Cl2, is synthesized by the method of solid-phase reactions. The compound has monoclinic symmetry, space group C2/m, a = 12.392(8) Å, b = 3.8040(14) Å, c = 7.658(5) Å, β = 122.64(5)°, and V = 304.0(3) Å3. The structure contains one symmetrically independent position of the Pb2+ cation coordinated by three O2? anions (Pb2+-O2? = 2.29–2.34 Å) and five Cl? anions (Pb2+-Cl? = 3.35–3.57 Å). The Cd2+ cation has a symmetric coordination with the formation of two bonds Cd-O = 2.15 Å and four bonds Cd-Cl = 2.73 Å. The oxygen atom is tetrahedrally coordinated by three Pb2+ cations and one Cd2+ cation, which leads to the formation of oxo-centered heterometallic OPb3Cd tetrahedra. The tetrahedra are linked together into chains through common Pb atoms and into layered complexes due to sharing of the equatorial Cd atoms. The chlorine atoms are located above the cavities of the oxo-centered layer.  相似文献   

15.
The synthesis and X-ray characterization of a novel chiral two-dimensional condensed metal–organic coordination polymer, bis(S-(-)-lactate)zinc(II) (1), are reported. Its crystal structure determination shows that a chiral cavity with approximate dimensions of 5.4×5.4 Å2 is present. Crystallographic data for 1, C6H10O6Zn, monoclinic P21, a=7.4440(15), b=7.4550(15), c=7.4550(15) Å, β=95.73(3)°, V=429.48(15) Å3, R1=0.0272, wR2=0.0751.  相似文献   

16.
The crystal structures of cis-1,6-cyclodecanediol ( 1 ) and of the molecular compound formed between cis and trans-1,6-cyclodecanediol in the ratio 2:1 (2) have been established by X-ray diffraction. The two substances are closely isostructural. (Crystal data: both monoclinic, P21/c, Z = 6; ( 1 ) a = 6.665(6), b = 18.074(3), c = 14.351(8) Å, β = 119.77(6)°, V = 1500(2) Å3; (2) a = 6.679(8), b = 18.074(4), c = 14.314(10) Å, β = 119.64(8)°, V = 1502(3) Å3). The asymmetric unit of the molecular compound contains one cis molecule in a general position and one trans molecule at a center of symmetry. In the crystal of the pure cis diol a set of disordered cis molecules mimics the corresponding centrosymmetric trans molecules in the molecular compound. The molecules have the stable BCB cyclodecane ring conformation, except for the disordered cis molecules, which have a conformation about 2 kJ mol−1 higher in energy (molecular mechanics calculations). The intricate three-dimensional hydrogen-bond network found in both crystals is presumably especially favorable from an energetic viewpoint.  相似文献   

17.
The energetic material 3‐(4‐aminofurazan‐3‐yl)‐4‐(4‐nitrofurazan‐3‐yl)furazan (ANTF) with low melting‐point was synthesized by means of an improved oxidation reaction from 3,4‐bis(4′‐aminofurazano‐3′‐yl)furazan. The structure of ANTF was confirmed by 13C NMR spectroscopy, mass spectrometry, and the crystal structure was determined by X‐ray diffraction. ANTF crystallized in monoclinic system P21/c, with a crystal density of 1.785 g cm−3 and crystal parameters a=6.6226(9) Å, b=26.294(2) Å, c=6.5394(8) Å, β=119.545(17)°, V=0.9907(2) nm3, Z=4, μ=0.157 mm−1, F(000)=536. The thermal stability and non‐isothermal kinetics of ANTF were studied by differential scanning calorimetry (DSC) with heating rates of 2.5, 5, 10, and 20 K min−1. The apparent activation energy (Ea) of ANTF calculated by Kissinger's equation and Ozawa's equation were 115.9 kJ mol−1 and 112.6 kJ mol−1, respectively, with the pre‐exponential factor lnA=21.7 s−1. ANTF is a potential candidate for the melt‐cast explosive with good thermal stability and detonation performance.  相似文献   

18.
A series of poly(aryl ether ketone)s (PAEK) copolymers containing phthalazinone moieties were synthesized by modest polycondensation reaction from 4‐(4‐hydroxyl‐phenyl)‐(2H)‐phthalazin‐1‐one (DHPZ), hydroquinone (HQ), and 1,4‐bis(4‐fluorobenzoyl)benzene (BFBB). The Tg values of these copolymers ranged from 168 to 235°C, and the crystalline melting temperatures varied from 285 to 352°C. By introducing phthalazinone moieties into the main chain, the solubility of these copolymers was improved in some common polar organic solvents, such as chloroform (CHCl3), N‐methyl‐2‐pyrrolidinone (NMP), nitrobenzene (NB) and so on. The values of 5% weight loss temperatures were all higher than 510°C in nitrogen. The crystal structures of these copolymers were determined by wide‐angle X‐ray diffraction (WAXD), which revealed that they were semicrystalline in nature, and the crystal structure of these copolymers was orthorhombic, equal to poly(ether ether ketone ketone)s. As phthalazinone content in the backbone varied from 0 to 40 mol % (mole percent), the cell parameters of these copolymers including the a, b, and c axes lengths ranged from 7.76 to 7.99 Å, 6.00 to 6.14 Å, and 10.10 to 10.19 Å, respectively. The degree of crystallinity (via differential scanning calorimetry) decreased from 37.70% to 16.14% simultaneously. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1744–1753, 2007  相似文献   

19.
The structure of a biologically active binuclear palladium complex, namely, [(dipy)Pd(μ-cysH) (μ-cys)Pd(dipy)]3+ · 3NO 3 ? · 4.5H2O (dipy = 2,2′-dipyridyl, C10H8N2; cys = cysteine, C3H7NO2S), has been determined from X-ray diffractometry data. The compound crystallizes in the triclinic system, symmetry space group P1, with the unit cell parameters a = 13.863(1) Å, b = 13.819(1) Å, c = 12.170(1) Å, α = 122.13(1)°, β = 103.61(1)°, γ = 91.40(1)°, V = 1887.02 Å3, Z = 2, and ρ = 1.82 g/cm3. The final discrepancy factor is R1 = 0.0495 for 12884 symmetrically nonequivalent reflections with F 0 ≥ 4σ(F 0), wR2 = 0.1071, and GooF = 0.978. The unit cell contains two chemically equivalent but crystallographically independent positively charged binuclear palladium complexes, six NO 3 ? anions, and nine water molecules. The π-π stacking interaction between the nearest pyridyl rings of the neighboring layers takes place. Moreover, the interlayer and intralayer interactions occur through van der Waals interactions and a complex three-dimensional system of hydrogen bonds, which are formed by water molecules, NH 3 + groups, and carboxyl groups.  相似文献   

20.
《Dyes and Pigments》2006,68(1):27-31
A monoazo dye, 2′,6′-dichloro-4-dimethylaminoazobenzene (C14H13Cl2N3) was synthesized and characterized by X-ray diffraction, IR, 1H NMR, and elemental analysis. The title molecule crystallizes in the monoclinic system space group P21/c (#14), a = 10.782(1), b = 8.9610(9), c = 15.108(2) Å, β = 103.008(5)°, V = 1422.2(3) Å3, Z = 4. The title molecule is not planar and takes trans-geometry and the two phenyl rings are twisted around the central linkage in opposite directions. In the crystal, molecules are interacted through π⋯π interaction, forming ‘double chains’ along [1 −1 0]. The ‘double chains’ are extended along [001] through H-Bond C11–H6⋯Cl2, C5–H3⋯Cl1 forming double layers (110), which are in turn interacted by C3–H1⋯Cl1 H-Bond [010], forming crystals. The molecular geometry has been calculated using the ab initio restricted Hartree–Fock and density functional method (B3LYP) with 6-311G** basis set. The optimized geometric parameters obtained by two methods are similar and in good agreement with the experimental values.  相似文献   

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