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 31 毫秒
1.
用X-射线衍射法测定了[C5H4C(CH3)(C3H7)CH2CH= CH2]NdMg2(μ3-OH)(μ3-Cl)(μ2-Cl)3(THF)4Cl的晶体结构。它属三斜晶系,空间群为P1- ,a= 12.698(3), b= 13.616(3), c= 13.712(3), α= 68.91(3), β= 84.34(3), γ= 63.07(3)°, V= 1966(1)3, Mr= 849.74, Dx= 1.412 g·cm - 3, μ= 1.7297 m m - 1, F(000)= 840, Z= 2, R= 0.073, w R= 0.086(I≥3σ(I))。分子中Nd(Ⅲ)原子的配位数为八,形成一个严重扭曲的八面体结构。两个Mg 原子的配位情况相似,它们的配位数都是六,构成两个扭曲的八面体。这三个八面体通过三个共用平面联接  相似文献   

2.
3.
<正> The crystal and molecular structure of (μ-PhS) (μ-σ, n-CH3CH = CH)-Fe2(CO)6 has been determined by X - ray diffraction technique. The complex has chemical formula of C15H10O6SFe2 and Mr=129. 99. The crystals are monoclinic,space group P21/c,with α=11. 789(2),b= 7. 159(1),c = 20. 890(4) A ;β = 100. 89(2);V = 1731. 32 A3;Z=4,Dc=1. 65g·cm-3;F(000) = 863. 86. The final R and Rw equal 0. 0315 and 0. 0405 respectively for 2527 observed unique reflections.  相似文献   

4.
5.
Using ESR and IR spectroscopy, the structures of >Si(O–C·=O)(CH2–CH3) (1) and >Si(CH2–CH·–CH3)(CH2–CH3) (2) radicals were deciphered. The directions and kinetic parameters of reactions of intramolecular rearrangements in these radicals were determined. The reactions of hydrogen atom abstraction in radical (1) from the CH2 and CH3 groups were studied. It was found that the endothermic reaction of hydrogen atom abstraction from the methyl group occurs at a higher rate than the exothermic reaction with the methylene group. The differences are determined by changes in the size of a cyclic transition state. Based on the experimental data, the strengths of separate C–H bonds in surface fragments are compared. The rearrangement >Si(CH2–CH·–CH3)(CH2–CH3) >Si(C·(CH3)2)(CH2–CH3) was discovered and its mechanism was determined. One of its steps is the skeletal isomerization Si- (2)- . (1)Si- (1)- . (2). Experimental data are analyzed using the results of quantum-chemical calculations of model systems.  相似文献   

6.
在密度泛函理论B3LYP/6-311++G(d,p)及MP2/6-311++G(d,p)水平上研究了单电子锂键复合物Y…Li—CH3[Y=CH3, CH2CH3, CH(CH3)2, C(CH3)3]的结构与性质. 结果表明, 三种单电子锂键复合物H3CH2C…Li—CH3(II), (H3C)2HC…Li—CH3(III)和(H3C)3C…Li—CH3(IV)单电子锂键强度依II(-26.7 kJ·mol-1)相似文献   

7.
The stability of the complex (μ-H)Os3(μ-OCNMe2)(CO)9PPh2CH2CH=CH2 (1), which contains a free unsaturated functional group in the terminal ligand PPh2CH2CH=CH2, with respect to isomerization, chelation of the ligand, and other transformations in solutions was examined. No transformations of complex1 were observed in the course of synthesis from (μ-H)Os3(μ-OCNMe2)(CO)9NMe3 or upon heating in solution. Complex1 as well as complexes (μ-H)Os3(μ-OCNMe2)(CO)9PHPh2 and (μ-H)Os3(μ-OCNMe2)(CO)9PPh3, which were formed as admixtures, were isolated in the solid state and identified by1H,1H-{31P}, and1H-{1H} NMR, IR, and Raman spectroscopy and mass spectrometry. For Part 52, see Ref. 1. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1455–1460, August, 2000.  相似文献   

8.
<正> The red transparent crystals of the title complex C22H14O7SFe2 (Mr=534.0996) crystallize in triclinic space group Flwith cell parameters:a = 9. 939(6),b= 10. 065(5), c= 12. 344(7) A;a=73. 95(4),B=79. 07(4),y=74. 77(4) ;V= 1135. 87A;Z=2;Dc=1.56g.cm-3;F(000) = 540. 0. The final R and Rwis 0.089 and 0. 086 for 3051 observed unique reflections. The ligand u-a,n-p-CH3C6H4C(O)CH=CH in the title complex is coordinated to two Fe atoms.  相似文献   

9.
10.
The title complex Cu2(μ-PhCOO)2(μ-CH3COO)2(CH3OH)2 1(C20H24Cu2O10, Mr=structure was determined by X-ray diffraction method. Complex 1 belongs to orthorhombic, space group Pbca with a = 13.083(6), b = 8.078(4), c = 21.566(2)(A), V = 2279(2) (A)3, Z = 4, Dc= 1.607g/cm3, F(000) = 1128,μ(MoKa) = 1.918 mm-1, the final R = 0.0506 and wR = 0.1382. Each Cu(Ⅱ)ion is coordinated by five oxygen atoms from two benzoic acids, two acetic acids and one methanol molecule in a slightly distorted square pyramidal environment. The title molecules construct a 2-D complex 1 displays strong emissions. IR and TG-DTA studies are also presented.  相似文献   

11.
The reaction of Sn[CH(SiMe3)2]2 and ethyne at ambient temperature affords a mixture of products, from which the title compound has been separated and identified by IR, 1H, and 13C NMR spectroscopy.  相似文献   

12.
Asymmetric telechelic polyisobutylene, α-PIB-ω), carrying the olefinic head group α = (CH3)2 C[dbnd]CHCH2- and tertiary chlorine endgroup ω = -C(CH3)2Cl has been synthesized by the use of the (CH3)2C[dbnd]CHCH2Cl/BCl3 initiating system. Highest yields were obtained by using methylene chloride diluent at about ?50°C. The presence and position of the olefinic head-group was proven by epoxidation/titration and epoxidation/cleavage. The presence and position of a tertiary chlorine endgroup was proven by initiating block polymerization of a second monomer, such as styrene or α-methylstyrene, by using the asymmetric telechelic polyisobutylene prepolymer in conjunction with Et2AlCl coinitiator. According to I/DP versus 1/[M] plots obtained in model block copolymerization experiments, with the use of the tert-BuCl/Et2AlCl initiating system at ?30°C, significant chain transfer to monomer occurs during blocking of styrene; however, monomer transfer is negligible during blocking of α-methylstyrene. Thus, under suitable conditions head-functionalized block copolymers (CH3)2C[dbnd]CHCH2-PIB-b-PαMeSt virtually free of homopolymer contaminants can be obtained.  相似文献   

13.

Reaction of (Me 2 SnBr) 2 w -(CH 2 ) 3 with 2,2'-bipyridine (bpy) in benzene affords, in the presence of small amounts of water, crystals of the novel composite [Sn 2 (H 2 O) 2 Br 2 Me 4 { w -(CH 2 ) 3 }2bpy] ( 1 ). The crystal structure of 1 consists of alternating layers of either organotin bromide or bipyridine molecules, each bpy molecule being configured cis oid and linked with the organotin layer via one O-H > N hydrogen bond. The mutual disposal of the molecules in the bpy bilayer differs from that known for pure, crystalline bpy. Cell parameters: a 24.3499(1), b 6.5112(1), c 23.3262(1) Å; g 119.557(1). Monoclinic, space group C 2/ c , D calc =1.750 g/cm 3 , Z =4; final R 1: 0.0529; wR 2=0.1374 for 3638 unique reflections [ R (int)=0.0676; I >2 ( I )].  相似文献   

14.
The complex [Pt2(μ-pp3)2] (pp3 = P(CH2CH2PPh2)3), produced by treatment of [PtH(pp3)]+ with sodium amalgam, has been shown to react with methyl iodide to give [PtMe(pp3)]+. The new complexes have been characterized by 1H, 31P and 195Pt NMR spectroscopy.  相似文献   

15.
Protonation of triosmium clusters Os3(-H)(CO)9(3-,2-CC-R) (R=CMe2OH, C(Me)=CH2) affords a cationic complex containing a six-electron propargyl ligand which has been detected for the first time.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1144–1145, June, 1993.  相似文献   

16.
林进  张萍  王昭煜  王宏根 《结构化学》1999,18(3):188-191
用X-射线晶体结构衍射法测定了[C5H4C(CH3)2CH2CH=CH2]Sm(OH)Cl·2MgCl2·4THF的晶体结构。它属三斜晶系,空间群为P^-1,a=10.773(2),b=12.836(3),c=15.478(3)A,a=111.46(3),β=107.71(3),γ=92.54(3)°,V=1868(1)A^3,Mr=827.91,Dx=1.472g/cm^3,μ=2.0006mm  相似文献   

17.
A neutral triosmium alkylidyne carbonyl cluster containing the 4-vinylpyridine (4vpy) moiety [Os3(µ-H)2(CO)93-CNC5H4-CH=CH2)] (1) has been prepared as red crystalline solids in good yield. Monomer (1) was copolymerized with styrene in the presence of ,'-azobis(isobutyronitrile) (AIBN) in chloroform at 60°C and a polymer-immobilized alkylidyne cluster of osmium was obtained. To compare the spectroscopic properties with the copolymers, a structurally similar repeating unit of the copolymers, [Os3(µ-H)2(CO)9(µ-3-CNC5H4-CH2CH3)I](2), has also been synthesized and characterized.  相似文献   

18.
One of the products of the reaction of the activated cluster Os3(CO)11(NCMe) with As(p-tol)3 in refluxing nonane has been shown by spectroscopic and X-ray crystallographic methods to be Os3(CO)93-AsC6H4CH3)(μ3-C6H3CH3), which contains a benzyne moiety bonded asymmetrically from one carbon to one osmium via a σ bond and from a second carbon to form a bridge between the remaining two osmium atoms.  相似文献   

19.
Russian Journal of Coordination Chemistry - Three new binuclear aqua-bridged nickel(II) 2-methylpropionate complexes [Ni2(μ-OH2)(μ-O2CCH(CH3)2)2L2–4((CH3)2CHCO2)2] (L is...  相似文献   

20.
Abstract

We have synthesized and characterized two novel Sr compounds: [Sr(μ-ONc)2(HONc)4]2 (1, ONc ? O2CCH2CMe3), and Sr5?O)(μ3?ONep)4(μ?ONep)4(HONep)(solv)4 [ONep ? OCH2CMe3, solv = tetrahydrofuran (THF), 2a; 1-methyl-imidazole (Melm), 2b], that demonstrate increased solubility in comparison to the commercially available Sr precursors. The two metal centers of 1 share four unidentate bridging μ-ONc ligands and complete their octahedral geometry through coordination of four monodentate terminal HONc ligands. The structural arrangement of the central core of 2a and 2b are identical, wherein four octahedral Sr atoms are arranged in a square geometry around a μ4-O ligand. An additional seven-coordinated Sr atom sits directly atop the μ4-O to form a square-pyramidal arrangement of the Sr atoms, but the apical Sr-O distance is too long to be considered a bond. In solution, compound 1 is disrupted forming a monomer but 2a and 2b retain their structures.  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