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1.
题目所指化合物晶体属单斜晶系,空间群P2_1/a,晶胞参数a=10.256,b=14.809,c=7.171,B=103.4°晶胞中分子数Z=4,晶体密度Dc=1.62gcm~(-3)。由直接法和傅里叶(Fourier)综合解得粗结构,经块对角矩阵最小二乘修正,偏离因子R为0.047。N→Si配位键键长为2.062,三个五员环近乎120°角相交,扭角分别为18.64°,19,34°和18.45°。环上的C(12),C(22),C(32)均偏离环的同一侧,三个环呈风扇形,两个氯原子与三个氧原子呈交叉构象。  相似文献   

2.
题目所指的化合物是在β位引入羰基扩环而形成六元环的新化合物,是杂氮三环研究中一个有意义的结构模型。它属正交晶系,空间群为Pha2_1,晶胞参数为a=16.913,b=8.138,c=6.123;晶胞内所含的分子数Z=4;计算密度Dc=1.457g·cm~(-3)。 使用PW-1100四圆衍射仪,MoKα射线收集衍射强度。用直接法和付立叶综合解得结构,取3°≤2θ≤50°的630个可观测独立反射数据,经最小二乘法修正,最终偏离因子R=0.088。在化合物中,N→B键长为1.637。  相似文献   

3.
题目所指化合物属单斜晶系,P2_1/c空间群,晶胞参数a=6.751(1),b=11.274(3),c=13.134(4),β=100.390(3)°,晶胞含分子数Z=4.用直接法和Fourier综合解得粗结构,取1490个可观测独立反射数据,经最小二乘修正,偏离因子R为0.056。三个五员环(Si,O,C,C,N)中各最大扭角分别为33.2°,23.0°,35.1°,其中最小者(23.0°)属于含羰基的环。  相似文献   

4.
题目所指的化合物(NC_6H_(10)O_4Si-CH_2CH_2CH_2Cl)属正交晶系,所属空间群为P2_12_12_1。晶胞参数:a=12.943,b=11.477,c=8.273。Z=4。取1243个可观测独立反射数据,用直接法和Fourier综合解得粗结构,经最小二乘修正,偏离因子R为0.049。三个五员环(Si,O,C,C,N)都有一个较大的扭角,分别为23.7°,41.6°,42.8°。其中带羰基环的最大扭角相对较小(23.7°)。三环最小二乘平面间夹角接近120°,分子中的氯丙基-CH_2CH_2CH_2C1近乎在一个平面上折叠。  相似文献   

5.
本文使用作者编制的X射线直接法(GC-80)程序系统测定了1-腈丙基杂氮硅三环(1-Cyanopropylsilatrane)(NC(CH_2)_3Si(OCH_2CH_2)_3N)晶体的三维空间结构。该晶体属正交晶系,Pna2_1空间群。a=12.797(3),b=11.843(2),c=8.163(2),D_(obs)=1.296克·厘米~(-3),D_(calc)=1.301克.厘米~(-3),z=4。用直接法求解出模型结构后,再用方块对角矩阵最小二乘法精化结构参数。对于1040个可观测衍射点,最终的R值为0.078。结构分析的结果表明,Si原子以五配位的形式存在,构成了略呈歪扭的三角双锥体。Si—N之间的配位键长2.164(4),Si—C的键长为1.884(5),N—Si—C之间的键角为178.9(4)°。  相似文献   

6.
作者曾对具不同环骨架和不同R取代基的杂氮硅三环(silatrane,简称硅三环)进行过研究.其中硅与R间均为Si—C键.标题化合物中高电负性的卤素与硅直接成键,因而是一组考察硅三环各种性质的典型化合物.  相似文献   

7.
β-六硝基六氮杂异伍兹烷的合成及晶体结构   总被引:2,自引:1,他引:2  
从苄胺和乙二醛出发 ,通过缩合、氢解脱苄及硝解三步合成了高张力多环笼形化合物———六硝基六氮杂异伍兹烷 (HNIW) ,它是迄今为止密度及能量水平最高的高能量密度化合物 .β HNIW的晶体结构表明 ,它是由 2个五元环及 1个六元环构成的笼形结构 ,每个桥氮原子上各连有 1个硝基 ,—NO2 基本位于一平面内 ,C—C键长为 0 1 5 6~ 0 .1 5 9nm ,比标准的sp3 C—C键长 0 0 0 2~ 0 .0 0 5nm .晶体学数据为 :正交晶系 ,空间群Pca2 1,a =0 .96 70 ( 2 )nm ,b =1 .1 6 1 6 ( 2 )nm ,c =1 .30 32 ( 3)nm ;V =1 .46 38( 5 )nm3 ,Z =4,Dc=1 .989g·cm-3 (Dm=1 .982 g·cm-3 ) .  相似文献   

8.
杂氮硼三环-3-酮的晶体属正交晶系,空间群为D_2~4-P2_12_12_1。晶胞参数a=17.098,b=7.709,c=5.712。晶胞内分子数Z=4,分子式为C_6O_4BNH_(10)。 X射线衍射强度数据由PW1100四圆衍射仪收集,采用CuKα辐射。独立衍射点832个,可观察点660个。用直接法(MULTAN-78)获得晶体结构,经全矩阵最小二乘法修正结构参数,R=0.074。最后沿N→B方向计算了分子的Newman投影。  相似文献   

9.
对由二乙烯三胺与联苯甲酰合成的标题化合物进行了MS、IR、UV、NMR谱的表征及X射线单晶衍射结构分析.该化合物M_r=277.39,晶体属P2_1/n空间群,晶胞参数a=0.9442(2)nm,b=1.4344(4)nm,c=1.1824(3)nm.β=112.92(2)°,Z=4,D_c=1.25g·cm~(-3).晶体结构由直接法解出,1827个可观察衍射参与最小二乘法修正,最终偏差因子R=0.050.结果表明标题化合物是一非平面型,具有部分不饱和键的氮杂稠二环化合物,其母体六元环为椅式构型、五元环为半椅式构型,2个取代苯基间的夹角为73.5°.  相似文献   

10.
用 ( -) -4 R-苯基唑烷酮为手性诱导试剂 ,N-端保护的 N-乙酰氯与 1 ,5 -苯并硫氮杂反应合成了 5个具有光学活性的 1 ,5 -苯并硫氮杂 -β-内酰胺衍生物 ,并通过 1 H NMR,MS,IR,[α]2 0D 和元素分析对此类化合物进行了表征 ,用 X射线衍射法确定了产物 b的立体结构 .晶体 X射线衍射分析结果表明 ,化合物 b属单斜晶系 ,P2 1 2 1 2 1 空间群 ,晶胞参数 :Mr=5 5 3.0 5 ,a=1 .2 2 93( 2 ) nm,b=2 .6 0 2 6 ( 5 ) nm,c=1 .0 1 4 6 ( 2 ) nm,β=90°,V=3.2 4 6 1 nm3 ,Z=4 ,Dc=1 .31 2 g/ cm3 ,F ( 0 0 0 ) =1 34 4 ,R1 =0 .0 5 84 ,w R2 =0 .1 1 4 0 .该化合物分子中七元杂环为类椅式构象 ,四元环上连接的两个取代基在环的同侧  相似文献   

11.
<正> The transparent colourless crystal of the title compound crystallized in monoclinic system with space group P21/c and cell dimensions a=9.857(7), b=11.128(4), c=16.036(7) A, β=103.31(5)°, V=1711.7A3, Z=4, Dc= 1.25 g.cm-3, λ =-1.5418 A, μ= 13.067 cm-1. The structure was solved by direct methods and refined by full matrix least-squares, the final discrepancy factor R=0.061 and Rw=0.060. The skeleton of the molecule is composed of three five-membered rings with a common edge N(l)-Si(l), and the dihedral angles between each two of the three rings are 110.5°, 107.9° and 105.0° respectively. The N(l)-Si(l) coordination bond length is 2.143(3) A. In comparison with the structures of other related compounds, it was found the N-Si bond length varies with the electronegativities of the substitute groups R at Si atom.  相似文献   

12.
本文报告了(C_5H_5FeC_5H_4CH_2N(CH_3)_3)_2B_(10)H_(10)晶体的结构。该晶体属三斜晶系、空间群为P_1~-。晶胞参数为:a=10.043(2),b=10.513(7),C=15.094(10),a=85.01(6),β=97.58(3),Υ=94.87(3)°,V=1625.7~3,Z=2。晶体在室温下用CAD-4四圆衍射仪收集衍射强度数据(MoKa),用重原子法解出铁原子坐标,综合应用E图、Fourief合成和差Fourier合成解出其他非氢原子坐标,按SDP加氢程序等求解阳离子中40个氢原子位置。各原子坐标及热振动参数经全矩阵最小二乘方修正,对于2258个独立衍射点(I≥3σI)],偏离因子R=0.043。 结构分析表明,B_(10)H_(10)~(2+)阴离子和C_5H_5FeC_5H_4CH_2N(CH_3)_3~+阳离子分别按畸变的八面体和畸变的三角形配位。两个二茂铁季铵阳离子中,两对戊二稀环平面间距为3.271(5)。阳离子中主要键长平均值为:Fe-C=2.026,C—C(环)=1.401,C—N=1.503。B_(10)H_(10)~(2+)阴离子为四方(三角)十六面体笼状结构,主要键长平均值为:B—B(顶点到正方形平面原子)1.706A,B—B(其它原子间)=1.830。  相似文献   

13.
Abstract

This is a report of the broad range of reactions and products that occur in refluxing xylene when π-cyclopentadienylcobalt or (π-cyclopentadienyl)-dicarbonylcobalt react with either symmetric or unsymmetrical acetylenes, specially when one of the substituents of the acetylene is an aromatic moeity. Since these reactions produce a variety of products, several of which are cis- and trans- tetrasubstituted cyclobutadiene-cobalt isomers, mnr and mass spectral methods were used to distinguish between them. In order to obtain an independent and indisputable structure assignment for the structural isomers investigated by spectral techniques, the crystal structure of the title compound was investigated by x-ray crystallographic techniques. The compound crystallizes in space group Pbca with the following cell dimensions: a = 29.622(7), b = 9.967(2) and c = 17.140(3) Å; V = 5060.46 Å3; D(exp) = 1.23(2) gm-cm?3, D(calc) = 1.24 gm-cm?3 for Z = 8 molecules/unit cell. The intensity data were collected with MoKα radiation (Λ = 0.71069 Å) using a computer-controlled diffractometer equipped with a graphite monochromator. In all 6331 reflections were collected of which 3173 were independent and had F 0 2 ± 3[sgrave] (F 0 2). The data were corrected for absorption and the transmission coefficients ranged from 0.72 to 0.79. The (π-cyclopentadienyl) ring is planar and has normal Co–C and C–C distances which average 2.049(7) and 1.389(17) Å, respectively. The Co–(Cp ring centroid) distance is 1.67 Å and the ring librates about this axis to a small degree which is not, however, large enough to affect the C–C distances. The average value of the C–C–C angle in the π-cyclopentadienyl ring is 108° indicating that it is planar and, in fact, the largest deviation of any carbon from the least-squares plane is 0.006 Å. In the Co-cyclobutadiene moiety, the Co–C and C–C distances are 1.982(15) and 1.467(3) Å and the Co–(cyclobutadiene ring centroid) distance is 1.69 Å. The angle between the normals of the five- and four-membered rings is 1.6°. The phenyl rings and trimethylsilyl fragments have normal distances and angles and the phenyl rings are planar. The two silicon and two carbon atoms of the phenyl rings linked to the π-cyclobutadiene moeity are out of the mean plane of the ring and bend away from the Co atom.

Finally, and most important, the four-membered ring is planar (the largest deviation from planarity is 0.003 Å) and the four C–C distances are the same length; however, the internal angles are not 90.0°. Instead, the two angles at carbons bonded to phenyl rings have values of 88.1(2)° and 88.4(2)° while those at carbon atoms bonded by silicons have values of 91.6(2)° and 91.8(2)°. The final discrepancy indices for this structural analysis were R 1 = 0.038 and R 2(F) = 0.044.  相似文献   

14.
标题化合物C18H18N2O2是由亚苄基丙二睛和5,5-二甲基-1,3-环己酮在乙二醇中反应2小时得到,结构通过单晶X-射线衍射法确定,其晶体属单斜晶系,空间群P21/c,Mr=294.34,a = 11.3070(1), b= 9.4750(1),c = 14.919(2) ,β= 99.34(1)埃琕 = 1577.1(3) 3,Z = 4,Dc=1.240Mgm-3,μ=0.082mm-1,F(000)=624, 最终的偏离因子为R=0.0381,wR=0.0961,在分子结构中存在3个环:苯环(A)、吡喃环(B)及与吡喃环稠合的六员环(C)。A与B、A与C及B与C之间的两面角分别为 92.5°、85.7°和8.2°。  相似文献   

15.
The crystal structure of the title compound, C16H8N6, contains two independent mol­ecules with no significant difference in their structures. The pyrazine ring makes dihedral angles of 36.7 (2) and 36.5 (3)° with the two pyridine rings in one mol­ecule, and 43.1 (2) and 38.4 (1)° in the other. The dihedral angles between the two pyridine rings are 58.2 (2) and 56.0 (2)°, respectively. The favoured orientation of the pyridine rings is such that their N atoms face each other.  相似文献   

16.
Molecules of the title compound [systematic name: 2,4,6‐(pentafluorophenyl)‐1,3,5,2,4,6‐trioxatriborinane], C18B3F15O3, are located on crystallographic twofold rotation axes which run through the boroxine and one of the pentafluorophenyl rings. The boroxine ring (r.m.s. deviation = 0.027 Å) and the pentafluorophenyl rings (r.m.s. deviations = 0.004 and 0.001 Å) are essentially planar. The dihedral angles between the boroxine and the two symmetry‐independent benzene rings are 8.64 (10) and 8.74 (12)°. The two benzene rings are mutually coparallel [dihedral angle = 0.80 (11)°]. The packing shows planes of molecules parallel to (01), with an interplanar spacing of 2.99 Å. Within these planes, all the molecules are oriented in the same direction, whereas in neighbouring planes the direction is inverted. Short B...F contacts of 3.040 (2) and 3.1624 (12) Å occur between planes. The geometric parameters of the boroxine ring in the title compound agree well with those of comparable boroxine structures, while the packing reveals some striking similarities and differences.  相似文献   

17.
Phenothiazine-10-propionitrile, C12H8SNC2H4CN, crystallizes in the centrosymmetric monoclinic space group P21/n, with a = 5.785(1)Å, b = 15.427(3)Å, c = 14.497(4)Å, β = 92.50(1)°, Z = 4, Dmeas = 1.29(1) g cm3 and Dcalc = 1.28 g cm3 at 23°. Three dimensional X-ray data were collected with a manual diffractometer using MoKα (λ 0.71069Å) radiation and by multiple film Weissenberg techniques using CuKα (λ 1.5418Å) radiation. The structure was determined by Patterson and Fourier methods and refined with 519 observed reflections by full matrix least-squares methods to an R of 0.077. The dihedral angle between the two planes of the o-phenylene rings is 135.4(3)°. In the folded heterocyclic ring the C-S-C angle is 97.8(7)° and the average C? S bond is 1.76(1)Å. A comparison of this structure to that of phenothiazine-10-propionic acid shows the two chemically similar molecules have the same dihedral angles in spite of completely different solid state packing patterns.  相似文献   

18.
A gas electron diffraction study yielded the following geometrical parameters for hexamethylcyclotrisilazane: r(Si-N) = 1.728 ± 0.004 Å, r(Si-C) = 1.871 ± 0.004 Å, r(C-H) = 1.124 ± 0.007 Å, ∠N-Si-N = 108.4 ± 1.0°, ∠Si-N-Si = 126.8 ± 0.8°, ∠C-Si-C = 108.9 ± 2.3°, ∠H-C-H = 111.6 ± 0.9°. The (SiN)3 ring was found to be puckered but the deviation from planarity is relatively small. Details of the ring shape could not be determined. The degree of ring puckering in six-membered rings with alternating atoms can be roughly predicted from the bond angles in analogous non-cyclic molecules.  相似文献   

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