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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.
应用一个简单新方法,在锌粉存在和常温常压下,(Ph_2PPy)_2NiCl_2与CO作用得到新配合物(Ph_2PPy)_2Ni(CO)_2。对后者经X衍射测定了晶体及分子结构,该晶体属正交晶系P_(cab.)晶胞参数为:a=12。044(3),b=21。322(5),c=24.925(5),Z=8.R=0.051和R_w=0.055,该分子中的镍原子配位为四面体构型。  相似文献   

3.
邻甲基苯荒酸四乙基铵盐分别与硝酸银和氯化铜反应,经毗啶重结晶,得到四核银簇合物Ag_4(o-CH_3C_6H_4CS_2)_4(Py)_4(晶体Ⅰ)和二核铜化合物Cu_2(o-CH_3-C_6H_4CSS_2)_2(Py)_(晶体Ⅱ)。用X射线单晶衍射法测定了它们的晶体结构。晶体Ⅰ的空间群为P2/n。晶胞参数:a=14.757(4),b=12.231(3),c=15.183(4)A,β=91.14(2)°,V=2739.95A~3,Z=2。2590个衍射点参与修正,最终偏差因子R=0.087。晶体Ⅱ的空间群为C_1~1-P1。晶胞参数:a=9.307(7),b=9.546(7),c=10.119(8)A,α=95.06(9),β=109.74(10),γ=118.86(10)°,V=705.94A~3,Z=1。1198个衍射点参与修正,最终偏差因子R=0.086。 Ag_4(o-CH_3C_6H_4CS_2)_4(Py)_4分子中Ag_4呈蝴蝶状构型,其配位情况与四核银簇合物Ag_4(a-C_(10)H_7CS_2)_4(Py)_4相似。Cu_2(o-CH_3C_6H_4CSS_2)_2(Py)_2分子构型与Cu_2(a-C_(10)H_7CSS_2)_2(Py)_2十分相似。Cu—Cu键长为2.608A。而且邻甲基苯荒酸与Cu~(2+)反应包括一个氧化还原反应,也与a-萘荒酸与Cu~(2+)反应相似。可以认为邻甲基苯荒酸与a-萘荒酸有相似的空间效应和电子效应。  相似文献   

4.
以二乙酰丙酮氧钒VO(Acac)_2与间硝基苯甲酰肼m-NO_2PhCONHNH_2分别在乙醇和甲醇中反应,得[VO(C_(12)H_(12)N_3O_4)(C_2H_5O)]_2(Ⅰ)和[VO(C_(12)H_(12)N_3O_4)(CH_3O)]_2(Ⅱ)两种晶体。晶体(Ⅰ)属空间群P(?),晶胞参数a=8.123(2),b=10.409(5),c=10.822(4),α=65.78(3)°,β=85.50(3)°,r=89.04(3)°。晶体(Ⅱ)属空间群P2_1/a,a=7.745(2),b=19.164(5),c=10.787(4),β=107.87(2)°。两个晶体均具有共同的结构特征:通过缩合形成的三齿配体占据四个赤道配位位置中的三个,男一个赤道配位位置由醇氧基RO~-所补充而RO~-中的氧原子又兼作桥氧向另一个钒原子的第六位配位,从而导致文献中未报道过的新型双核钒配合物的形成。  相似文献   

5.
四核银原子簇化合物Ag_4(α-C_(10)H_7CS_2)_4(Py)_4·2Py由α-萘荒酸与硝酸银在有机溶剂中反应,经吡啶重结晶获得单晶。由于反应中采用不同的银盐与α-萘荒酸的投料比(1:2与1:4),得到了两种颜色的晶体(甲和乙)。用X射线单晶衍射法测定了它们的晶体结构。晶体甲的空间群为C_(2h)~5—P2_1/a。晶胞参数:a=2.2822(4)(?),b=12.803(4)(?),c=24.444(7)(?),β=103.90(2)°,V=6933.14(?)~3,Z=4。晶体乙的空间群为c_(2h)~6—c2/c。晶胞参数:a=29.150(2)(?),b=12.789(3)(?),c=24.413(2)(?),β=130.56(4)°,V=6914.38(?)~3,Z=4。Ag_4(α-C_(10)H_7CS_2)_4(Py)_4在两种晶体中的空间构型基本相同,差别只在于分子的对称性上。晶体乙中,分子处在二重轴上,分子的对称性较高。本文只报道晶体乙的结构测定和结构参数.3338个反射参与修正,最终的偏差因子R=0.093。分子中Ag_4呈压扁的四面体构型。六个Ag—Ag距离可分成两类,硫桥相连的Ag—Ag平均键长为2.924(?)(2.875—2.972(?)),表明有相当程度的金属键相互作用。不与硫桥相连的Ag—Ag距离为3.563(?)。  相似文献   

6.
本文合成了钴与磷酸二丁酯(HDBP)的络合物,经分析鉴定,其组成为Co(DBP)_2·3Py·CHCl_3(Py=吡啶),对络合物的热谱、红外、可见光谱及磁性进行了研究。得到了该络合物的单晶。结构研究表明,该晶体属于三斜晶系,P空间群,晶胞参数:α=14.490(10),b=15.721(7),c=20.109(12),α=90.37(4)°,β=96.04(5)°,γ=105.63(4)°。晶体中每2个钴通过2个DBP桥连成一个二聚分子,[Co(DBP)_2·3Py]_2,分子中有对称中心,晶胞中含有二个[Co(DBP)_2·3Py]_2分子和四个氯仿分子。每个钴除了与2个桥式的DBP上的氧配位外,还与3个吡啶上的N和一个DBP上的氧配位。  相似文献   

7.
文珂  卫革成 《结构化学》1992,11(3):208-211
氯化钆与对-甲基苯基锂在四氢呋喃中反应得到产物之一为[Li(THF)_4][GdCl_4-(THF)_2],(M_r=738.2),在-70℃下进行X-射线衍射研究。其晶体属单斜晶系,P2/n空间群。晶体学参数为a=13.263(2),b=8.474(1),c=14.961(0);β=99.72(1)°,V=1657.23(?)~3,Z=2,D_c=1.48g/cm~3,F(000)=750,μ_c=24.2cm~(-1),最终偏离子为R=0.0614。研究结果表明,本题晶体是离子型晶体,围绕Gd~(3+)的四个Cl~-离子和两个THF分子的氧原子构成畸变的八面体。Li~+周围的四个THF分子的氧原子构成一个近似的四面体。  相似文献   

8.
α'-(BEDT-TTF)_2C_6H_4(SO_3)_2的合成、结构与导电性   总被引:1,自引:0,他引:1  
用恒电流电化学结晶法合成了一种新的基于BEDT-TIF的电荷转移盐α'-(BEDT- TIF)_2C_6H_4(SO_3)_2 [BEDT-TIF = 双亚乙基二硫四硫富瓦烯,C_6H_4(SO_3) _2~(2-) = 对苯二磺酸根]。通过四圆X射线衍射方法测定了α'-(BEDT-TTF) _2C_6H_4-(SO_3)_2的结构。晶体属于单斜晶系,P2/n空间群;晶胞参数:a = 0. 77937(17)nm, b = 0.66989(11) nm, c = 3.4422 (7) nm, β = 91.135(12) °, V = 1.7968(6) nm~3。该晶体中BEDT-TTF~+自由基沿a轴方向形成具有二聚体结构 的交错排列型柱状堆积,沿b轴方向由户并户强分子间相互作用形成一维分子链。 电荷补偿阴离子C_6H_4(SO_3)_2~(2-)则在a方向存在较强的作用。沿c轴方向, BEDT-TTF~+自由基层和阴离子层交替排列形成夹心式结构。α'-(BEDT-TTF) _2C_6H_4-(SO_3)_2在ab面的某方向的室温电导率为0.5913 Ω~(-1)·m~(-1),电 阻率-温度测定曲线表明它具有半导体导电行为。在150K附近,晶体发生了某种相 变。  相似文献   

9.
鬼灯擎素的结构分析   总被引:3,自引:0,他引:3  
郑尚珍  周忠远 《结构化学》1989,8(4):305-310
本文报道了从鬼灯擎(Rodgersid aesculifolia Batal)中提取的鬼灯擎素(Bergenin)晶体的结构研究。鬼灯擎素晶体为正交晶系,C_(14)H_(18)O_(10),M_r=346.28,其晶胞参数a=7.468(9),b=13.899(4),c=14.228(0)A;空间群为P2_12_12_1;晶胞内分子数Z=4,D_c=1.5560g/cm~3,结构模型由SHELXTL程序解出;经Fourier合成和最小二乘修正,最后的偏离因子R=0.028。此外,利用晶体结构分析所得分子中各原子的坐标,以半经验分子轨道法CNDO/2程序计算了分子总能量、净电荷分布以及Wiberg键级等,并以此讨论了分子的反应活性中心。  相似文献   

10.
报道了N-氧化吡啶-2-甲醛(Pio)与乙二胺(en)及1,3-丙二胺(tn)生成的双Schiff碱Cu(Ⅱ)配合物([Cu(Pioen)H_2O](ClO_4)_2和[Cu(Piotn)(H_2O)_2](ClO_4)2)的合成和晶体结构。晶体[Cu(Pioen)H_2O_3(ClO_4)_2属正交晶系,空间群P2_12_12_2,α=7.9534(19),b=7.6768(48),c=26.1037(189),Z=4,R=0.077 1,R_w=0.0771。晶体[Cu(Piotn)-(H_2O)_2](ClO_4)_2属正交晶系,空间群P~(nam),α=7.1360(24)。b=13.7887(42),0=22.2556(81),Z=4,R=0.0491,R_w=0.0491。结构由Patterson函数及Fourier合成法解出,经全矩阵最小二乘法修正至收敛。  相似文献   

11.
1 INTRODUCTIONTheα ,α ,α′,α′ tetraaryl 1 ,3 dioxolane 4,5 dimethanols (TADDOLS)diolswhicharereadilyavailablefromalkyltartrates ,havebeenwidelyusedaschiralligandsinenantioselectiveadditionreactionsofcarbon centerednucleophilestoaldehy des[1 ] ,in [2 +2 ]cycloadditions[2 ] …  相似文献   

12.
The molecular structure and crystal-packing mode of the enantiopure chiral building blocks Delta-[Ru(bpy)(2)(py)(2)][(+)-O,O'-dibenzoyl-D-tartrate].12H(2)O (I) and Lambda-[Ru(bpy)(2)(py)(2)][(-)-O,O'-dibenzoyl-L-tartrate].12H(2)O (II) have been determined by single-crystal X-ray diffraction data. This study proposes a model of how the L- and D-dibenzoyltartrate anions recognize the chirality of the hydrophobic [Ru(bpy)(2)(py)(2)](2+) complex. The monoclinic unit cell contains four complex cations, four tartrate anions, and 48 water molecules. Since there are no possibilities to form hydrogen bonds between the cations and anions, chiral recognition is due to crystal packing. Two benzoyl rings of two different tartrate anions are gripping the two bpy-planes of the Ru-complex. Further a third benzoyl ring from a tartrate anion is packed between the two pyridine rings, favoring one enantiomeric form to crystallize from aqueous solution. Crystal structure data for I at 153 K: a = 15.342(3) A, b = 19.200(4) A, c = 18.872(4) A, beta = 104.841(3) degrees, monoclinic space group C(2), R(1)= 0.0239 (I > 2sigma(I)), R(2) = 0.0606, Flack parameter = 0.0115 (with esd 0.0166). For II at 293 K: a = 15.376(4) A, b = 19.388(11) A, c = 19.085(7) A, beta = 105.11(2) degrees, monoclinic space group C121, R(1)= 0.0686 (I > 2sigma(I)), R(2) = 0.1819, Flack parameter = -0.0100 (with esd 0.0521).  相似文献   

13.
1 INTRODUCTION Hydrothermal synthesis of Mo(V) phosphates has allowed various structures, all characterized by the presence of identical clusters with the composition Mo12MP8X62 (X = O, OH) to be stabilized[1~6]. Many Mo(V) phosphates with such clusters have been iso- lated to date. The first compound was discovered by Haushalter and Lai[1] for M = Na with the formula (PPh4)2[(H3O)2NaMo6P4O24(OH)7]?5H2O. Recently, a second type of structure has been observed for M = Na (Na8(…  相似文献   

14.
1 INTRODUCTION The development of supramolecular complexes has recently attracted considerable attention due to the fundamental interest in self-assembly processes of transition-metal complexes, supramolecular che- mistry and crystal engineering[1]. The ultimate goal is to gain control in order to direct their function[2]. Self-assembly through coordination and nonco- valent interactions such as hydrogen bonds, aromatic π···π stacking, steric repulsion and Van der Waals forces leads …  相似文献   

15.
3-(Pyrrole-2'-carboxamido)propanoic acid I has been synthesized from the reaction of β-alanine methyl ester with 2-trichloroacetylpyrrole followed by saponifying and acidating in 85.4% yield, and the crystal structure of 3-(pyrrole-2'-carboxamido)propanoic acid· (1/2)H2O (C8H11N2O3.5, Mr = 191.19) was obtained and determined by X-ray diffraction method. The crystal is of monoclinic, space group C2/c with a = 19.010(4), b = 8.3515(17), c = 13.788(3) (A), β = 125.88(3)°, V = 1773.6(6) (A)3, Z = 8, Dc = 1.432 g/cm3, λ = 0.71073 (A), μ-MoKα) = 0.114 mm-1 and F(000) = 768. The structure was refined to R = 0.0354 and wR = 0.0942 for 1642 observed reflections with I > 2σ(I). It is revealed that the title compound has one pyrrole ring and one propionic acid subchain linked by an amido bond at C(4), and there are 8 molecules of com- pound I and 4 crystal water molecules in each unit cell. The supramolecular layers are stabilized by the hydrogen bonds of N(2) H…O(2), N(1) H…O(4), O(4) H(1W)…O(2) and O(3) H…O(1).  相似文献   

16.
1 INTRODUCTION Pyrrole and its derivatives have attracted much attention due to their chemical properties as well as biological activities[1]. They have been widely used to produce pharmaceutical, essences, biochemicals, etc. It has been found that a great number of pyrrole derivatives present antitumor and antiviral activi- ties[2 ~ 5]. During our searches for bioactive com- pounds, a series of pyrrole derivatives were synthe- sized[6, 7]. We report here the synthesis of 3-(pyrrole- 2?-…  相似文献   

17.
<正> Mr = 431,.6 orthorhombic,P212121,a = 8.526(2), b = 9.970(2), c= 29.787(6)X,Z=4,V=2532.0A3,Dc=1.132g.cm-3,λ(MoKα)=0.71073A,μ=0.67cm-1, F(000) = 952, final R= 0.069 for 1733 observed reflections with I>1σ(I). All six-membered rings in this free base are in the chair form and the five-membered ring C takes the envelope conformation, with the ring fusions A/B traps, B/C trans, C/D cis, D/E trans and E/F trans. There is one crystal water whose oxygen atom joins the adjacent alkaloid molecules by the inter-molecular hydrogen bonds O(1)-H... 0(3)-H(31)...0(2)=C(6). Pertinent parameters for the hydrogen bonding system are: .0(1)...0(3) 2.878(6), 0(2)...O(3) 2.917(6)A,O(1)-H...O(3) 178.3(3)°,and 0(3)-H(31)...0(2) 165.6(3)°.  相似文献   

18.
The title compound 4-(2-bromophenyl)-3,4,7,8-tetrahydro-7,7-dimethyl-1-p-tolylquinoline-2,5(1H,6H)-dione 1 (C24H24BrNO2, Mr = 438.35) was synthesized and characterized by IR, 1H NMR and elemental analysis. The crystal belongs to monoclinic, space group C2/c with a = 27.565(14), b = 10.079(5), c = 15.917(8) A,β = 111.059(9)°, Z = 8, V = 4127(4)A3, Dc = 1.411 g·cm^-3,μ(MoKa) = 2.011 mm^-1, F(000) = 1808, the final R = 0.0417 and wR = 0.1032 for 2393 observed reflections (I 〉 2σ(I)). X-ray analysis reveals that the pyridine ring adopts a distorted boat conformation, while another six-membered ring takes a half-chair conformation. In addition, there are non-classical hydrogen bonds of C-H…O and C-H…Br in the structure. The short distance (3.481A) between the adjacent 2-bromophenyl rings indicates the existence of π-π interaction.  相似文献   

19.
The title compounds, C32H28N2O4, (I), and C32H28N2S4, (II), respectively, are tetra­substituted pyrazines and both possess Ci symmetry. They differ only in the hetero atom (X) of the –­CH2XPh side‐arm substituents: X = O in (I) and S in (II). Compound (I) has an overall S‐shape with a pair of adjacent –­CH2OPh side arms alternately above and below the plane of the central pyrazine ring. The phenyl rings are inclined to one another by 12.63 (18)° and there is one intra­molecular C—H⋯O hydrogen bond involving adjacent –CH2OPh side arms. In compound (II), adjacent –CH2SPh side arms point in opposite directions with respect to the pyrazine ring plane, with the phenyl rings inclined at 60.45 (8)°. Both structures have weak C—H⋯π inter­molecular inter­actions.  相似文献   

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