首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The crystal and molecular structure of the title compound (2) C21H16O4 has been determined by an X-ray analysis, by direct methods from diffractometer data and refined by full-matrix least squares. The compound (2) crystallizes in the space group P21/a, with cell parameters:a=36.432(5),b=5.512(3),c=8.269(5) Å, =108.0(3)°,z=4,D c =1.397 g/cm–3,R=7.8 for 1136 observed reflections. The conformation of the tetracyclic ring system shows a folding of two planar parts of the carbon skeleton about an axis passing thorough C8 and C16 of the seven membered ring C.  相似文献   

2.
The molecular and crystal structures of the title compound have been determined. The crystals are monoclinic: C2/c (15),a=21.787(7),b=7.025(6),c=20.165(8) Å,=96.03(2)°,V c =3069 Å3,Z=8,D x=1.36 mg m–3, =(Mo K)=0.71069 Å. The structure was solved by direct methods and refined with 1484 reflections to a finalR value of 0.057. Mass and spectral data (ir, uv,1H and13C nmr) are also reported. The structure appears to be polyolefinic having two independent push-pull systems on the fulvenic ring.  相似文献   

3.
The X-ray crystal structure of the title compound has been determined. The crystals are orthorhombic:Pcab, a=9.857(5),b=15.274(5),c=32.601(14) Å,V c =4908.4 Å3;Z=8;D x =1.279 Mg m–3; (MoK)=0.71069 Å;=0.88 cm–1,F(000)=2016, temperature of measurement 294 K. The structure was solved by direct methods, and refined with 932 reflections to a finalR value of 0.071. The two six-membered rings show distorted boat conformations and the tetrahydrofuran ring exhibits a half-chair conformation. Mass spectra, IR spectrum, and1H and13C NMR spectra are also reported.  相似文献   

4.
The crystal structure of 1-Methyl-3-([2,2-dimethyl-4,6-dioxo-1,3-dioxane-5-ylidene]methyl)urea (C9H12N2O5) has been determined by single crystal X-ray diffraction analysis. The crystals are monoclinic, a = 5.3179(2), b = 18.6394(6), c =10.8124(3) Å, β = 100.015(2)°, Z = 4, sp. gr. P21/c, R = 0.0381 for 2537 reflections with I > 2σ(I). Except for C(CH3)2 group, the molecule is planar. The structure is stabilized by inter- and intramolecular N-H...O hydrogen bonds and weak C-H...O interactions.  相似文献   

5.
在强酸性介质中,3,4-二乙酰基-2,5-己二酮与对氨基苯甲酸作用,满意地得到了4-(2,5-二甲基-3,4-二乙酰基)-1-吡咯基苯甲酸,用IR、1H NMR、高分辩质谱等对其进行了表征,用X射线衍射测定了晶体结构.该晶体属三斜晶系,P1空间群,a=0.80950(10)nm,b=0.81910(10)nm,c=1.1900(2)nm,α=101.600(10)°,β=98.820(10)°,γ=104.960(10)°,Z=2,Dc=1.364×103kg/m3.拟合了苯环平面和吡咯环平面的平面方程,并求出两平面之间的二面角为68.11°.  相似文献   

6.
7.
(2,2′-bipyrimidine)dinitratopalladium(II) forms a triclinic crystal in space groupP?1 witha=7.605(5) Å,b=8.791(4) Å,c=12.632(5) Å, α=85.11(3)0, β=78.79(4)0, γ=77.45(4)0,V=807.7(7) Å3, andZ=2. The Pd atom exhibits square planar coordination geometry with mean Pd?O=2.206(7) Å, Pd?N=1.990(5) Å, O?Pd?O=92.0(2)0, and N?Pd?N=81.0(2)0. The complexes associate across an inversion center with Pd...Pd=3.190(2) Å. The bipyrimidine ligand is bowed with a 5.9(2)0 dihedral angle between the C4N2 rings. The nitrate ions are on the same side of the N2O2 donor atoms plane and make 60.4(2)0 and 66.6(2)0 dihedral angles with that plane.  相似文献   

8.
在酸性介质中,3,4-二乙酰基-2,5-己二酮与硝基苯胺作用,满意地得到了2,5-二甲基-3,4-二乙酰基-1-(硝基苯基)吡咯,用IR、1HNMR、高分辨质谱等对其进行了表征,并用X射线衍射测定了2,5-二甲基-3,4-二乙酰基-1-(3-硝基苯基)吡咯的晶体结构.该晶体属单斜晶系,P21/c空间群.晶体学数据如下:a=0.9375(1)nm,b=1.2814(2)nm,c=1.2985(1)nm,β=100.96(1)°,V=1.5315(3)nm3,Z=4,M=300.31,Dc=1.302×103kg/m3.  相似文献   

9.
10.
The crystal structure of the title compound is determined by X-ray diffraction studies. The structure is solved by the direct method. The experimental data are obtained on a DAR-UMB diffractometer by the θ-θ/2θ scan technique using MoK α radiation. The crystal is monoclinic, a = 17.913(3) Å, b = 17.239(3) Å, c = 5.501(5) Å, γ = 74.4(3)°, space group P21/a, Z = 4 for C17H22N4O, and ρcalcd = 1.211 g/cm3. The molecule consists of the phenyl and triazole rings and the dimethylamino, carbonyl, and isopropyl groups attached to the rings. The dihedral angle between the rings is 67.4°. The carbonyl oxygen atom and the triazole ring are in the trans position relative to each other. The N-C-C-O torsion angle is 172.8°. The molecule is in the Z isomeric form.  相似文献   

11.
Crystals of the title compound are monoclinic (C26H25NO): space groupP21/c,a=16.565(3),b=10.328(2),c=12.621(3) Å,=104.02(3)°. The structure was solved by direct methods and refined by block-matrix least-squares to giveR=0.056 andR w =0.061 for 1613 reflections above 2(I). The amide moiety is tilted by 19.3(2)° with respect to the mean aromatic ring plane. The two othergem phenyl rings subtend a dihedral angle of 112.2(4)° to each other. The molecules are joined in the solid by N-HO hydrogen bonds.  相似文献   

12.
13.
The structure of the title compound, C18H23N3O4, was determined by X-rays.M r =344.40, triclinic, space groupP¯1,a=8.163(4),b=9.230(2),c=13.297(2) Å,=102.70(2),=103.58(3)°,=102.50(3)°,V=911.3 Å3,Z=2,D c =1.26 Mg m–3. CuK radiation (graphite crystal monochromator,=1.54178 Å),(CuK)=7.50 cm–1,T=290 K. Final conventionalR-factor=0.068,R w =0.079 for 1912 unique reflections and 295 variables. The structure was solved usingMultan andDirdif. The title compound is the first example of a 3,6-tetrasubstituted dioxopiperazine adopting a folded conformation, owing to a direct interaction between the dioxopiperazine ring and the aromatic side chain.  相似文献   

14.
以3-硝基-4-氯苯甲醛和5,5-二甲基-1,3-环己二酮为原料,二甲基甲酰胺为溶剂,不需催化剂合成一种新的氧杂蒽二酮开环衍生物2,2'-(3-硝基-4-氯苯基)次甲基双(3-羟基-5,5-二甲基-2-环己烯-1-酮)晶体,确定最佳反应条件是:芳醛和脂肪环酮的摩尔投料比为1∶2,反应温度为80℃,反应时间为lh;并对其进行熔点、元素分析、红外光谱、氢核磁共振及X-射线单晶衍射测定.该晶体为单斜晶系,空间群=P21/n,a=1.95777(13)nm,b=1.22720(9) nm,c=1.99687(14) nm,β=107.719(2).,V=4.5700(6) nm3,Z=8,dc=1.302 g/m3,μ =0.205mm-1,F(000)=1888.  相似文献   

15.
The crystal structure of the 4-methylpyridine adduct of bis[1-(2-thienyl)-4, 4,4-trifluoro-1,3-butanedionatolnickel(II) was determined by a three-dimensional x-ray analysis using counter data. The crystals are monoclinic,C2/c, witha = 9.330,b = 18.278,c = 17.855 Å, and = 95.1°. The structure was refined by full-matrix least squares toR = 0.10. The molecule has a two-fold axis, and both enantiomers withcis configuration occur in the crystal. The solvation by 4-methylpyridine is shown to weaken the chelate bonds in the same way as doestrans hydration.  相似文献   

16.
The crystal and molecular structure of the title complex has been determined. The space group isP21/n, witha=8.460(3),b=8.503(3),c=20.341 (8) Å,=98.41(3) andZ=2. The ligand molecules chelate the CuII such that the metal has a tetragonally distorted octahedral geometry; four N atoms occupy the equatorial plane and two H2O molecules occupy the axial positions. The average Cu-N and Cu-O distances are 2.005(6) and 2.47(1) Å, respectively. The novel ligand, 1,1-dimethyl-2,2-diimidazolylsulfide was formedin situ from a methanolic solution of copper(II) sulfate pentahydrate and 1-methylimidazole-2-thiol. The measured spectral parameters (visible, EPR, and photoelectron spectroscopy) correlate well with the molecular structure.  相似文献   

17.
The crystal structure of 1-(2-aminoethyl)biguanide-isothiocyanato-copper(II)thiocyanate, [Cu(aebg)(NCS)] (SCN) (aebg = NH2. CH2. CH2. N=C(NH2). NH. C(NH). NH2) has been determined and refined by Fourier methods using three-dimensional X-ray data collected on a Weissenberg automatic diffractometer. The unit cell parameters are:a = 11·41(2),b = 8·81(2),c = 7·45(2) Å; = 87·6° (2); = 67·2° (2); = 70·1° (2);Z = 2.Assuming space group P¯1, the structure was refined down toR = 8·5 %. The coordination around Cu is slightly distorted square planar and concerns three N atoms from the aebg ligand (Cu-N = 1·988(8), 2·019(7), 1·963(5) Å) and the terminal N of an isothiocyanate group (Cu-N = 1·941(5) Å). Two unsymmetrical, long interactions (Cu-N = 3·367(7) and 2·947(7) Å), with the N atoms belonging to two NCS groupstrans with respect to the coordination plane, complete the coordination to a distorted octahedron. In the aebg ligand the double bonds are localized on the C-N groups, whose nitrogen atoms coordinate to the metal.This work was carried out with the aid of financial support from the Consiglio Nazionale delle Ricerche, Roma.  相似文献   

18.
6,7-dideoxy-1,2;3,4;9,10-tris-O-(1-methylethylidene)-d-erythro-α-d-galacto-undecopy- ranosid-8-ulose, 3, was formed by adding a D-galactose-derived dithiane nucleophile to a protected erythronolactone followed by reductive removal of the dithioacetal group. Its β-anomer crystallizes in the chiral trigonal space group P3221 with a=b=12.2649(19) Å, c=24.675(8) Å, and Z=6. The molecule is composed of an erythrofuranose and a galactopyranose moiety, linked by a flexible ethylene bridge. The pyranose part of the molecule is disordered over two positions with equal occupancy. The configuration of the two disordered moieties is the same and they are converted into each other by a slight rotation of 6 degrees around one of the C–C single bonds of the ethylene bridge. The disorder allows for a more effective packing in the solid state.Supplementary material CCDC-602051 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, by e-mailing data_request@ccdc.cam.ac.uk or by contacting The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44(0)1223-336033.  相似文献   

19.
The crystal structure of methyl-3,4-dideoxy-3-(salicylidenylamino)--d-erythro-pentopyranoside has been determined by vector verification and successive Fourier syntheses, and refined by full-matrix least-squares calculations toR o = 0.063 for 596 observed reflections. The crystals are orthorhombic, space groupP212121, witha = 10.781(2),b = 12.075(2),c = 10.008(1) Å, andZ = 4.All substituents to the pyranose ring aresyn-clinal with respect to corresponding bonds in the ring. The atoms in the salicylidenylamino moiety, including H(13), are coplanar within experimental error. This group includes a very weak intramolecular hydrogen bond with N(I)-O(13) = 2.585(9) Å, O(13)-H(13)-N(1) = 122 °.  相似文献   

20.
1-(o-Tolyl)-naphthalene was obtained in the synthesis of the 1,8-disubstituted analogue. Crystallographic analysis established orthogonal alignment of the ring systems, in agreement with calculations to investigate the existence of rotamers due to restricted rotation.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号