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1.
本文报导从绵毛马兜铃(Aristolochia Mollissima Hance)中提取的一种结晶体K,C_(15)H_(20)O_2的分子及晶体结构。晶体属于正交晶系,晶胞参数为:a=6.543(2),b=13.972(3),c=14.732(2),空间群为P2_12_12_1,Z=4,d_(cal)=1.15g/cm~3。结构模型由SHELXTL程序解出,经最小二乘修正,最后的一致性因子R=0.055。 结构测定表明,分子内存在一个10员二烯环和一个5员内酯环,它们共有一个碳—碳双键。5员内酯环呈平面构型,且与10员环的最小二乘平面相互垂直。  相似文献   

2.
合成了R,S一三[N-(邻-氧α-萘亚甲基)-α-苯乙胺]合钴。x射线单晶衍射衍射测定了晶体结构及分子的绝对构型。晶体属正交晶系,D_2~4-P2_12_12_1空间群,晶胞参数:α=12.587(3),b=14.166(3),c=25.652(14)(?),v=4574.2(?)~3,z=4。用重原子法及差值Fourier合成解出结构,最后的R值为0.074。利用Co~( )对CuKa反常散射测定了分子的绝对构型。Co~( )为六配位,d~2sp~3杂化近正八面体构型。  相似文献   

3.
报道了标题化合物合成和晶体结构。X-射线结构分析表明,该化合物的分子式为C39H58BrO10P,Mr = 797.74,晶体属于单斜晶系,空间群为P21,晶胞参数a = 12.858(3), b = 25.130(5), c = 14.125(3) ? = 105.15(3), V = 4405(2) ?, Z = 4, Dc = 1.203 g/cm3, ?= 1.019 mm-1, F(000) = 1688,R = 0.0726, wR = 0.1201,共收集到9691个独立衍射点,其中可观测点5638个(I≥2s(I))。每个分子中有6个环,13个手性中心,2个五员环呈信封式构象,并分别与三员环组合成[2.4]螺环和[3.1.0]桥环化合物,4个新生成的手性中心的绝对构型为C(6)(S), C(7)(S), C(3)(R), C(2)(R),新引入的磷酸酯官能团C(9)为S构型。  相似文献   

4.
白头翁配基G(C_(30)H_(48)O_4)晶体的空间群是P2_12_12_1,晶胞参数为:a=12.5925(2),b=13.245(2),c=15.923(2);Z=4(Dobs=1.12,Dcalc=1.182g·cm~(-3))。晶体结构用直接法和电子密度函数解出。在这个不对称分子中,四个六元环构型均属椅式,并且彼此间通过ee键稠合。晶体中存在三种O-H…O分子间氢键。  相似文献   

5.
本文合成了单羟基桥连的双铜(Ⅱ)大环穴醚配合物[Cu_2(OH)(ClO_4)(C_(16)H_(38)N_6)](ClO_4)_2 ·CHCl_3,并测定与讨论了它的晶体结构.晶体属于正交晶系,空间群为D_2~4 -P2_12_12_1,晶胞参数:a=12.749(4)(?),b=14.361(3)(?),c=18.064(3)(?),V=3307.3(13)(?)~3,Z=4。分子结构中单羟基桥连两个二价铜离子,Cu-O平均键长为1.935(6)(?),Cu-OH-Cu键角为135.2(2)°;铜原子的几何构型为畸变四方锥,配体的底面为穴醚的二乙三胺亚基的三个氮原子和一个羟基桥氧原子;顶点位置为高氯酸根的氧原子,因为该原子同时配位于另一个铜原子,所以分子的双铜中心存在第二个氧桥,即较弱的高氯酸根桥;Cu-O(ClO_3)距离分别为3.005(9)(?)和2.806(8)(?).  相似文献   

6.
合成的标题化合物用X射线衍射方法确定其分子的绝对构型,晶体空间群为P_(2_1 2_1 2_1),晶胞参数:a=0.8365(3)、b=0.8625(3)、c=2.3513(2)nm,Z=4.结构分析表明,分子骨架中存在3个环结构,即含磷、氮原子的船式七元环、椅式六元环以及由碳原子组成的信封式五元环。P—S键为e键,P—O键为a键。  相似文献   

7.
从d-樟脑出发,经六步反应合成了一种新的樟脑酮亚胺衍生物——7,7-二甲基一双环[2.2.1]-2-(苄)亚胺-10-(N-邻羟基苯基)酰胺(2)。化合物的晶体的晶胞参数a=8.6904(9),b=10.9400(16),c=20.8583(33)A;z=4.V=1983.06(o.45)A~3;属P2_12_12_1空间群。用反常散射法测定分子的绝对构型为1S,4R,并讨论了该化合物作为不对称反应合成子的立体选择性的影响因素。  相似文献   

8.
采用X射线分析测定了标题化合物的晶体结构和分子结构。化合物C_(20)H_(22)-O_2N_4P_2S4(1)为反式构型,M_r=540.63,正交晶系,空间群Pcab,a=7.255(2),b=18.297(3),c=18.576(2),V=2465.9 ~3,Z=4,D_c=1.456g/cm~(-3),最终偏离因子R=0.058,R_ω=0.049;化合物(2)为顺式构型,单斜晶系,空间群Ic,a=14.649(5),b=7.009(2),c=22.694(8),β=100.60(3)°,V=2290.1 ~3,Z=4,D_c=1.643g/cm~(-3),最终偏离因子R=0.061,R_ω=0.065。晶体结构测定结果表明,这对顺反异构体的构象明显不同:反式异构体的分子本身有对称中心且与晶体学对称中心重合,氧,氮,磷杂六员环为椅式构象,磷硫单键为轴向键,磷硫双键为平伏键;顺式异构体的分子本身无对称中心,两个氧氮磷杂六员环分别为椅式和船式构象,环上的磷硫单键为平伏键,磷硫双键为轴向键,与反式异构体恰恰相反。  相似文献   

9.
[C_5H_7S_2]_2[(SbCl_3)_2S]的晶体结构   总被引:1,自引:1,他引:1  
[C_5H_7S_2]_2[(SbC1_3)_2S]的晶体结构采用x射线衍射法测定。晶体属于卑斜晶系,空间群C2/c,a=14.531(2),b=11.265(2),c=15.364(3),B=112.72(1)°,Z=4。在CAD-4四圆衍射仪上收集数据,用重原子法解出结构并经全矩阵最小二乘法修正。R=0.067。研究表明,该离子晶体中,[C_5H_7S_2]~+的C、S骨架具有平面构型,而[(SbCl_3)_2S]~(2-)的构型是:Sb原子周围形成缺位的准三角双锥构型,两个Sb准三角双锥通过共用S桥形成二聚体,∠Sb-S-Sb=98°,整个阴离子具有C_2对称性。  相似文献   

10.
施剑秋  程培元 《结构化学》1992,11(6):471-475
冬凌草甲素,C_(20)H_(28)O_6,Mr=364.44,是一种从中药中提取的抗癌药,它的晶体结构分析表明晶体属正交晶系的空间群P2_12_12_1,晶胞参数为α=13.316(9),b=21.302(2),c=13.015(1),V=3697(9)~3。Z=8,D_c=1.31g/cm~3,D_o=1.30g/cm~3,F(000)=1568。该分子是四环二萜类化合物,A环和C环是椅型结构,B环是船型结构;D环是部分共轭五员环,为半椅型结构,环上相邻的两个双重键侧基组成一个六原子的共轭平面。  相似文献   

11.
Crystal and molecular structure of the ethanol solvate of 2-[bis(diphenylphosphoryl)methyl]phenol, C31H26O3P2·3/4 C2H5OH (I), was determined by X-ray diffraction analysis. Crystals I are monoclinic: a=11.896(3), b=17.207(3), c=28.421(6) Å, β=90.75(2)°, Z=8, space group P21/c. The structure of I was solved by direct methods and refined anisotropically by large-block least-squares analysis to R=0.066 (CAD-4 automatic diffractometer, λMoKα radiation, 3650 independent reflections with I≥3σ). The crystal structure of I contains two independent molecules, Ia and Ib, of the basic substance and two independent solvate molecules of ethanol. The P atoms in molecules Ia and Ib have distorted tetrahedral environments; the average bond lengths are: P=O 1.476(3), P-C(sp3)=1.833(4) and P-C(Ar)=1.809(4) Å. Molecule Ia has an approximate symmetry plane Cs. The conformation of molecule Ib differs from that of Ia in rotation of one diphenylphosphoryl substituent around the P-C(sp3) bond by an angle of ≈34°. In molecule Ia, the O=P-C-P=O fragment has the form of a chela with two nearly parallel P=O bonds. In the crystal structure of I there are O-H...O=P intermolecular H-bonds; in molecules Ia and Ib there is an intramolecular H-bond of C-H...OH type.  相似文献   

12.
标题化合物C19H23O4Cl(4)是由邻氯苯甲醛(1)与5,5-二甲基-1,3-环己二酮(2)、2,2-二甲基-1,3-二氧六环-4,6-二酮(3)在乙醇中反应而得。结构通过单晶X-射线衍射分析确定,其晶体属于单斜晶系,空间群晶体结构用直接法解出,使用全矩阵最小二乘法对原子参数进行修正,最后的偏离因子R=0.034,Rw=0.042。在晶体结构中存在一个共轭的烯醇结构。单晶X-射线分析表明;平面1(C(1)~C(6)、Cl)和平面2(C(8)~C(10)、C(12)、C(13))之间的两面角为97.11°,原子C(7)呈变形的四面体构型。  相似文献   

13.
Jia D  Zhao Q  Zhang Y  Dai J  Zuo J 《Inorganic chemistry》2005,44(24):8861-8867
New lanthanide thioantimonate(V) compounds, [Ln(en)3(H2O)x(mu(3-x)-SbS4)] (en = ethylenediamine, Ln = La, x = 0, Ia; Ln = Nd, x = 1, Ib) and [Ln(en)4]SbS4.0.5en (Ln = Eu, IIa; Dy, IIb; Yb, IIc), were synthesized under mild solvothermal conditions by reacting Ln2O3, Sb, and S in en at 140 degrees C. These compounds were classified as two types according to the molecular structures. The crystal structure of type I (Ia and Ib) consists of one-dimensional neutral [Ln(en)3(H2O)x(mu(3-x)-SbS(4))]infinity (x = 0 or 1) chains, in which SbS4(3-) anions act as tridentate or bidentate bridging ligands to interlink [Ln(en)3]3+ ions, while the crystal structure of type II (IIa, IIb, and IIc) contains isolated [Ln(en)4]3+ cations, tetrahedral SbS4(3-) anions, and free en molecules. A systematic investigation of the crystal structures of the five lanthanide compounds, as well as two reported compounds, clarifies the relationship between the molecular structure and the entity of the lanthanide(III) series, such as the stability of the lanthanide(III)-en complexes, the coordination number, and the ionic radii of the metals.  相似文献   

14.
Thalassemia is a genetic blood disorder requiring life‐long blood transfusions. This process often results in iron overload and can be treated by an iron‐chelating agent, like deferiprone (3‐hydroxy‐1,2‐dimethylpyridin‐4‐one), C7H9NO2, in an oral formulation. The first crystal structure of deferiprone, (Ia), was reported in 1988 [Nelson et al. (1988). Can. J. Chem. 66 , 123–131]. In the present study, two novel polymorphic forms, (Ib) and (Ic), of deferiprone were identified concomitantly with polymorph (Ia) during the crystallization experiments. Polymorph (Ia) was redetermined at low temperature for comparison of the structural features and lattice energy values with polymorphs (Ib) and (Ic). Polymorph (Ia) crystallized in the orthorhombic space group Pbca, whereas both polymorphs (Ib) and (Ic) crystallized in the monoclinic space group P21/c. The asymmetric units of (Ia) and (Ib) contain one deferiprone molecule, while polymorph (Ic) has three crystallographically independent molecules (A, B and C). All three polymorphs have similar hydrogen‐bonding features, such as an R22(10) dimer formed by O—H…O hydrogen bonds, an R43(20) tetramer formed by C—H…O hydrogen bonds and π–π interactions, but the polymorphs differ in their molecular arrangements in the solid state and are classified as packing polymorphs. O—H…O and C—H…O hydrogen bonds lead to the formation of two‐dimensional hydrogen‐bonded parallel sheets which are interlinked by π–π stacking interactions. In the three‐dimensional crystal packing, the deferiprone molecules were aggregated as corrugated sheets in polymorphs (Ia) and (Ic), whereas in polymorph (Ib), they were aggregated as a square‐grid network. The characteristic crystalline peaks of polymorphs (Ia), (Ib) and (Ic) were established through powder X‐ray diffraction analysis. The Rietveld analysis was also performed to estimate the contribution of the polymorphs to the bulk material.  相似文献   

15.
Tri(meta-tolyl)antimony chloro(benzenesulfonate) (I) has been synthesized by the reaction between tri(meta-tolyl)antimony bis(benzenesulfonate) and tri(meta-tolyl)antimony dichloride (toluene; 0.5 h, 100°C). According to X-ray diffraction data, the antimony atoms in two crystallographically independent molecules Ia and Ib have a distorted trigonal bipyramidal coordination to chlorine and oxygen atoms in axial positions: OSbCl, 177.8(4)° (Ia), 178.6(4)° (Ib); CSbC, 114.0(9)°?127.6(8)° (Ia), CSbC, 114.4(8)°?128.0(8)° (Ib); Sb?C, 2.01(2)?2.139(18) Å, Sb?Cl, 2.453(7) Å, Sb?O, 2.163(13) Å (Ia), Sb?C, 2.07(2)?2.14(2) Å, Sb?Cl, 2.442(7) Å; Sb?O, 2.187(14) Å (Ib).  相似文献   

16.
合成了标题化合物并测定了其晶体结构。该化合物的化学式为C18H15O4BrCl2, Mr = 446.12。晶体为正交晶系, P212121空间群, 晶胞参数为: a = 7.1540(7), b = 23.367(1), c = 11.161(2) , V = 1865.7(3) 3, Z = 4, Dc = 1.588 g/cm3, F(000) = 896, (MoK? = 2.515 cm-1, R = 0.037, wR = 0.074, Flack系数为0.14(1)。晶体结构显示, 化合物中有2个手性碳原子, 为(2S,4R)构型, 整个分子呈沿b轴排列的波浪形的链状结构。  相似文献   

17.
本文报告用单晶X-射线衍射法测定[Nd_2O(C-5H_5)_6](C_(12)H_9N_2)_3C1·mC_4H_5O的晶体结构。晶体属于单斜晶系,空间群为P2-1/c,晶胞参数为a=20.982(15),b=11.217(7),c=32.954(32),β=104.17(7)°;Z=4。Nd和C1原子坐标用直接法定出,其他原子坐标以差Fourier方法求得,经过最小二乘法修正,R因子为0.159。在分子中三个茂环皆通过η~5。键与Nd原子配位,两个Nd原子间存在桥氧原子,因而形成(Nd_2O(C_5H_5)_6)~(2-)阴离子,Nd-C键基本上属于离子键。三个邻菲罗啉基团通过氢键与C1原子连接形成大的阳离子[(C_(12)H_9N_2)3-C1]~(2+)。  相似文献   

18.
标题化合物C23H25对O3Cl是由邻氯苯甲醛与5,5-二甲基1,3-环己二酮在N,N-二甲基甲酸腹中反应而得。结构通过单晶X-射线衍射法确定,其晶体属于单科晶系,空间群=1632。晶体结构用直接法解出,使用全矩阵最小二乘法对原子参数进行修正,最后的偏离因子为R=0.054,Rw一0.063。在晶体结构中,吡喃环与苯环之间的两面角为92.43°。  相似文献   

19.
史达清 《结构化学》1998,17(3):221-224
标题化合物C23H27O4Cl是由邻氯苯甲醛与5,5-二甲基-1,3-环己二酮在N,N-二甲基甲酰胺中反应而得。结构通过单晶X-射线衍射法测定,其晶体属于单斜晶系,空间群晶体结构用直接法解出,使用全矩阵最小二乘法对原子参数进行修正,最后的偏离因子为在晶体结构中,存在两个共轭的烯醇式结构。四个C-O健长分别为1.283(2),1.285(2),1.287(3)和1.298(2)  相似文献   

20.
The title compound (C20H21N3O4, Mr = 367.40) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction. The crystal is of orthorhombic, space group P212121 with a = 7.5143(15), b = 13.901(3), c = 18.545(4) , V = 1937.1(7) 3, Z = 4, Dc = 1.260 g/cm3, μ = 0.089 mm-1, F(000) = 776, the final R = 0.0616 and wR = 0.0912. X-ray diffraction reveals that the molecule adopts an E configuration about the central C=N double bond. The intermolecular O–H…O hydrogen bond stabilizes the crystal structure by causing the formation of a supramolecular architecture.  相似文献   

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