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1.
Several optically pure representatives of 2-hydroxy-3-[N-alkyl (aryl)] pinanoamines, potential chiral auxiliaries in organic synthesis, were obtained. In addition, a structural examination of 2-hydroxy-3-(N-n-butyl)-pinanoamine hydrochloride was conducted. Results of these studies confirm the structure of the amines obtained and the correctness of the proposed reaction pathway.Crystal data: C12H28NOCl,P21/c,a=13.196(1),b=8.562(1),c=14.276(1) Å,=110.41(3)°,R=0.034 for 2046 reflections.Part I,J. Cryst. Spec. Res. (1989)19, 535.  相似文献   

2.
We report here the reactivity of 6,7-epoxyhimachal-2-ene with dibromocarbene generated in situ by phase-transfer catalysis. The stereochemistry of products resulting from dibromocyclopropanation has been established by X-ray crystallography. Compound 3 is orthorhombic P212121 with a = 7.549 (1), b = 8.432 (1), c = 24.469 (1) Å, V = 1559.8 (5) Å3, Z = 4 and compound 5 is monoclinic P21 with a = 8.779 (1), b = 15.684 (1), c = 12.111 (1) Å, = 91.869 (1)°, V = 1666.7 (4) Å3 and Z = 4.  相似文献   

3.
The title compound crystallizes in the monoclinic space group P21/n, with a = 6.225(1), b = 14.612 (1), c = 15.520 (1) Å, = 96.6(3)°, Z = 4 and V = 1402.4Å3. The stereochemistry of the 7/5-fused ring system is trans, the 7-membered and the 5-membered rings are found to be in the chair and envelope conformations, respectively. This represents the first study of a compound containing the 7/5-ring skeleton shown in (3) below.  相似文献   

4.
Compounds (CN3H6)2[UO2(OH)2(NCS)]NO3 (I) and β-Cs3[UO2(NCS)5] (II) are synthesized and studied by IR spectroscopy and single-crystal X-ray diffraction. I and II crystallize in the orthorhombic system. For I, a = 12.2015(13) Å, b = 7.3295(8) Å, c = 16.310(2) Å, space group Pnma, Z = 4, and R = 0.0327; for II, a = 21.7891(6) Å, b = 13.5120(3) Å, c = 6.8522(2) Å, space group Pnma, Z = 4, and R = 0.0268. In structure I, complex groups form infinite chains [UO2(OH)2(NCS)] n n? belonging to the AM 2 2 M 1 crystal chemical group of uranyl complexes (A = UO 2 2+ , M 2 = OH?, and M 1 = NCS?). The main structural elements of crystals II are mononuclear [UO2(NCS)5]3? groups belonging to the AM 5 1 group of uranyl complexes (A = UO 2 2+ and M 1 = NCS?). In I and II, uranium-containing complexes are connected with outer-sphere cations by electrostatic interactions, and in I a system of hydrogen bonds also contributes to their binding. Specific features of the packing of complex [UO2(NCS)5]3? groups in the structures of two modifications of Cs3[UO2(NCS)5] are discussed.  相似文献   

5.
Crystallization of calcium nitrate from a toluene solution of triethyleneglycol (= 2,2-[1,2-ethanediylbis(oxy)]-bisethanol) resulted in the formation of the 1:2 solvate [Ca(triethyleneglycol)2](NO3)2·H2O. [Ca(C6H14O4)2](NO3)2·H2O is monoclinic, P21/c, a = 15.775(1), b = 8.660(2), c = 16.342(1) Å, = 91.239(7)°, V = 2232.1(6) Å3, Z = 4, and D c = 1.429 g cm–3. The eight-coordinate calcium has square antiprismatic geometry with two triethyleneglycol molecules straddling the metal center. The nitrate anions and water of crystallization are involved in hydrogen bonding with the alcoholic hydrogen atoms.  相似文献   

6.
3-Triphenylstannylcholest-5-ene (1) has been synthesised and its molecular structure has been determined by single crystal X-ray diffraction. Refinement in the triclinic space groupP1 witha=7.805(6),b=7.862(5),c=32.351(10)Å, =90.87(8), =94.77(8) and =101.15(4)o converged atR=0.063. One of the two crystallographically independent molecules in the unit cell has a patially disordered side chain. The bond lengths and valency angles about tin indicate some steric hindrance due to the proximity of one of the phenyl rings with the B ring of the steroid nucleus.  相似文献   

7.
Abstract The synthesis of the PPN (PPN=Ph3P=N=PPh3) salt of di-μ-iodo-dichlorocuprate (I) anion [Cu2I2Cl2]2− is described and the crystal and molecular structures of this compound are reported. It was found that the compound has the formula [PPN]2[Cu2I2Cl2]0.7[Cu2I4]0.3 (3). Compound 3 crystallizes in an orthorhombic crystal system, space group Pbca, with a = 19.654(3), b = 16.130(2), c = 20.108(3) ?, V = 6374.3(16) ?3 and Z = 4. The crystal contains 70% [Cu2I2Cl2]2− anions and 30% [Cu2I4]2− anions. This was also confirmed by MSES spectroscopy. The anion [Cu2I2Cl2]2− is planar and the Cu atoms have a trigonal planar configuration. Graphical abstract Synthesis and Crystal Structure of the Salt [PPN + ] 2 [Cu 2 I 2 Cl 2 ] 2− Andrey A. Yakovenko, Tatiana V. Timofeeva and Mikhail Yu. Antipin The title compound was synthesized and structurally investigated. The crystal contains 70% [Cu2I2Cl2]2− anions and 30% [Cu2I4]2− anions. This was confirmed by MS ES spectroscopy.   相似文献   

8.
The title complex was prepared by the addition of 15-crown-5, dissolved in acetone, to a solution of Y(NO3)3·nH2O in the same solvent. The crystal structure of this complex, determined by single-crystal X-ray diffraction using counter methods, was carried out on a crystal grown by slow evaporation of the reaction mixture at room temperature. [Y(NO3)3(OH2)3]·1.5(15-crown-5) Me2CO crystallizes in the acentric space group, P21, with unit cell dataa=15.900(5),b=16.530(6),c=11.821(5) Å,=92.12(3)°,D calc=1.53 g cm–3 forZ=4. Each unit cell consists of two dimers of the formula unit. One crown molecule bridges two [Y(NO3)3(OH2)3] units via hydrogen bonding with one water molecule of each. The two remaining water molecules per metal moiety form three hydrogen bonds to another 15-crown-5 molecule and one to an acetone molecule. The average bonding parameters in the nine-coordinate metal complexes are Y-O(NO3)=2.43(4) Å and Y-O(OH2)=2.34(5) Å.For Part 19 see Rogers, 1987.  相似文献   

9.
The X-ray crystal structure of trinuclear iron acetate [Fe3O(CH3COO)6(H2O)3]2 [ZnCl4] ? 2H2O was determined. The crystal has a ionic structure. It is monoclinic, a = 25.363(7), b = 14.533(4), c = 15.692(4) Å, β = 103.11(2)°, space group C2/c, and R = 0.0685. The structure of the cationic complex [Fe3O(CH3COO)6(H2O)3]+ is typical of trinuclear iron(III) compounds containing a μ3-O bridge: the iron atoms are situated at the vertices of an almost equilateral triangle with the O atom at the center. Each Fe atom is coordinated by four O atoms of bridging carboxy groups, the μ3-bridging O atom, and the water molecule in the trans position to the latter O atom. Mössbauer spectroscopy evidence indicates the high-spin state (S = 5/2) of the iron(III) ions.  相似文献   

10.
[NBu4][Br3] interacts with C6H6 to form an air-stable liquid clathrate. The tribromide anion reacts with phenol to give para-bromophenol in>95% yield. The HBr which is generated in the reaction combines with the Br anion to form [Br-H-Br]. The latter forms the basis for a new liquid clathrate, [NBu4][Br-H-Br]·n C6H6. The parent salt, [NBu4][Br3], crystallizes in the monoclinic space group C2/c witha=12.983(5),b=10.380(7),c=16.222(6) Å,=93.93(3)°, andD c =1.47 g cm–3 forZ=4. The final R value is 0.068 based on 787 observed reflections.  相似文献   

11.
The crystal and molecular structure of 11-dimethylamino-2-ethoxy-3-hydroxy-5-pregnan-20-one (Dethoxyprone, formII) (C25H43NO3) has been determined by direct methods, and refined to a finalR of 0.067 for 4508 observed reflections. The compound crystallizes in space groupP212121 with cell dimensionsa=10.830 (2),b=12.703 (2),c=17.490 (1) Å;Z=4,D x =1.12 g cm–3, (CuK )=5.28 cm–1. The rings of the steroid skeleton are trans connected. Rings A, B, and C have chair conformations, while ring D has a half-chair conformation. The molecules are hydrogen bonded in a head to tail fashion through the hydroxy and keto groups.  相似文献   

12.
A triterpenoid glycoside has been isolated from the roots of a herb used in traditional Chinese medicine. The molecular structure of this compound and its derivatives have been determined by spectroscopic studies and an X-ray analysis of the 2,3,23-triacetoxy-28-methyl ester of the aglycone. This aglycone belongs to the ursene structure series. The hydroxy group on ring E of these triterpenoids is orientated and the side chains at C(2), C(3), C(4) and C(17) are .,, and orientated, respectively. The C ring, which has a double bond at C(12)=C(13), adopts a sofa conformation.  相似文献   

13.
Heating a solid mixture of (NH4)3VS4, CuCl, PPh3, and NEt4Br at 100°C for 10 h and extraction with CH2Cl2 yielded [VS4(CuPPh3)4Br]·CH2Cl2. Crystallographic data: Triclinic, P1¯, a = 15.189(3), b = 20.093(6), c = 12.031(3) Å, = 102.39(2), = 100.05(2), = 82.86(2)°, V = 3517(3) Å3, and Z = 2. The configuration of the VS4Cu4Br core can be described as a distorted cubane with an additional face. The V atom has retained the tetrahedral geometry of the free [VS4]3– moiety. The four Cu atoms have three different coordination environments, strongly distorted tetrahedral, nearly trigonal planar, and strictly trigonal planar. The infrared, electronic, and 51V NMR spectra have also been reported.  相似文献   

14.
[HB(3,4,5-Me3pz)3]2Zn (1) and [H2B(3,4,5-Me3pz)2]Zn(-3,4,5-Me3pz)2Zn[H2B(3,4,5-Me3pz)2] (2) are present in equal amounts in a crystal in the triclinic space group, P-1 with a = 11.5924(11) Å, b = 12.7799(12) Å, c = 15.7317(14) Å = 107.905(2)° = 96.796(2)°, = 105.786(2)°, and Z = 1. The structure of 1 is a trigonally distorted octahedron and is very similar to the structure of [HB(3,5-Me2pz)3]2Zn showing that the introduction of the third methyl group on the pyrazolyl ring does not impact on structure. [H2B(pz)2]2Zn (3) is orthorhombic, Pca2(1) with a = 10.1473(3) Å, b = 11.1117(2) Å, c = 14.1831(5) Å, = = = 90° and Z = 4. The zinc(II) centers in both 2 and 3 are similar and have pseudotetrahedral structures.  相似文献   

15.
The tetrahedrane cluster Co3(Co)9(3-CCO2CH2CCH) reacts with Co2(CO)6 to furnish the pentacobalt compound Co3(CO)9[3-CCO2CH2CCH{Co2(CO)6}] in high yield. Functionalization of the pendant alkyne group by Co2(CO)6 was ascertained by IR and NMR spectroscopies (1H and 13C), and the solid-state structure of Co3(CO)9[3-CCO2CH2CCH{Co2(CO)6}] was unequivocally established by X-ray diffraction analysis. Co3(CO)9[3-CCO2CH2CCH{Co2(CO)6}] crystallizes in the triclinic space group , a = 7.9674(5), b = 13.208(1), c = 13.3094(9) Å, = 76.257(6), = 79.123(6), = 86.403(6)°, V = 1335.8(2) Å3, Z = 2, and d calc = 2.016 g/cm3. The electrochemical properties of Co3(CO)9[3-CCO2CH2CCH{Co2(CO)6}] were examined by cyclic voltammetry and the first reduction wave was found to be a reversible, one-electron reduction associated with the tricobalt moiety. No evidence for electronic communication between the Co3 and Co2 portions of the complex was observed. The results of extended Hückel MO calculations on Co3(CO)9[3-CCO2CH2CCH{Co2(CO)6}] establish the nature of the LUMO in Co3(CO)9[3-CCO2CH2CCH{Co2(CO)6}].  相似文献   

16.
The title compound, C20H14O8, Mr=382.3, crystallized from chloroform in the centric space group P¯1 witha=6.516(4),b=6.798(3),c=9.545(7) Å,=85.31(5),=73.87(5), =79.59(4)°,V=399.2 Å3, and Dcalc=1.59 g cm–3 forZ=1. Least-squares refinement of 1035 observed [Fo5(Fo)] reflections led to the final agreement index ofR=0.074. The molecule resides on a crystallographic center of inversion and is disordered into two different conformations. This manifests itself as a 50/50 disorder at O(4), C(2), and C(3). The observed structure reveals acis relationship between the bridgehead hydrogen atoms and the aryl rings. The 90 MHz1H nmr spectrum of the title compound exhibits an AAXX spin system with a H(1)C(2) to H(1)C(3) and H(1)C(2) to H(1)C(3) coupling constant of 2.8 Hz. Computer spectral simulation and Karplus equation analysis are utilized to illustrate a relaxation of the torsion angles between H(1)C(2) and H(1)C(3), and H(1)C(2) and H(1)C(3) is solution.  相似文献   

17.
Malonate-thiocyanate complex (NH4)3[UO2(C3H2O4)2(NCS)] · 2H2O is synthesized and studied by X-ray diffraction. The compound crystallizes in the monoclinic system: a = 13.9983(4) Å, b = 8.1947(2) Å, c = 16.4678(4) Å, β = 100.846(1)°, space group Cc, Z = 4, and R = 0.0158. The main structural units of the crystal are mononuclear [UO2(C3H2O4)2(NCS)]3? groups belonging to the AB 2 01 M 1 crystal chemical group of uranyl complexes (A = UO 2 2+ , B 01 = C3H2O 4 2? , M 1 = NCS?). Discrete uranium-containing groups are connected by electrostatic interactions with ammonium ions and by hydrogen bonds. Some specific structural features of crystals containing [UO2(L)2(NCS)]3? complexes, where L is the oxalate or malonate ion, are discussed.  相似文献   

18.
The crystal structures of the title compounds have been determined by single crystal diffraction methods. Crystals of the dysprosium compound are monoclinic, space groupP21/c witha=14.133(4),b=13.438(5),c=14.401 (4)Å,=103.98(2)°,V=2654(1)Å3,Z=4,D c =1.82 g cm–3, finalR=0.035. The Dy atom is eight-coordinate with a distorted dodecahedral coordination geometry involving two bidentate nitrate groups and four pyridone oxygen atoms. An erbium complex with analogous stoichiometry was also prepared but not structurally characterized. Crystals of the Gd compound are monoclinic, space groupP21/n, witha=11.226(2),b=9.075(2),c=16.737(3)Å,=93.88(3)°,V=1701(1)Å3,Z=2,D c =1.91 g cm–3, finalR=0.042. Each Gd atom is bonded to one pyridone oxygen atom, a water molecule and three bidentate nitrate groups. An oxygen atom of one of the bidentate nitrates additionally serves to bridge pairs of Gd atoms so as to form a dinuclear complex in which each Gd atom is nine-coordinate with a tricapped trigonal prismatic geometry. Crystals of L2HNO3 are monoclinic, space groupI2/a witha=12.479(4),b=6.535(2),c=14.297(6)Å,=96.07(3)°,V=1159(1)Å3,Z=4,D c =1.45 g cm–3, finalR=0.057. The pyridones are linked in pairs by very short (2.44 Å) symmetrical OHO hydrogen bonds. Each pair is further linked via a nitrate ion by means of N-HO(nitrate)H-N hydrogen bonds, so as to form an extended chevron-like pyridone-pyridone-nitrate-pyridone-pyridone array. Adjacent chains are linked via weak C-HO(NO3) interactions.  相似文献   

19.
The crystal and molecular structures of the 11 complexes sulfadimidine·2-aminobenzoic acid (I) and sulfadimidine·4-aminobenzoic acid (II) are described and compared with known structures containing sulfadimidine. In each complex, molecular association is maintained by one N-HO hydrogen bond, and one O-HN hydrogen bond involving the imino N and one pyrimidinyl N atom of sulfadimidine and the two carboxyl O atoms of the aromatic acid. The conformation of the sulfadimidine molecule inII is unusual for anN 1-substituted arylsulfonamide. Molecular dimensions for the complexed aminobenzoic acids are virtually the same as those reported for the free acids. Partial correlation between carboxylic acid strengths and the hydrogen bonded NO distances is observed in sulfadimidine complexes of this type.  相似文献   

20.
The crystal and molecular structure of [ZnCl2(N4-trzCH2COPh)2] (trz = 1,2,4-triazole) has been determined by X-ray crystallography. It crystallizes in the monoclinic system, space group C2/c, with lattice parameters a = 26.7892(4) Å, b = 4.9392(2) Å, c = 20.7872(1) Å, = 127.517 (1), and z = 4. The complex has C 2 symmetry. The coordination geometry of each Zn atom is distorted tetrahedral formed by two Cl atoms and two tertiary N atoms of the -(1,2,4-triazole-1-yl)-acetophenone ligands. The two equivalent Zn–Cl and Zn–N bonds form bond angles around the Zn(II) atom in the range 101.4(1)–120.8(1). C–H O intermolecular interactions link the molecules in infinite chains in the [101] direction.  相似文献   

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