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1.
The crystal structure of Ph3SnNCS has been determined by single crystal X-ray diffraction. The crystals are monoclinic, P21, a = 19.02(3), b = 11.67(2), c = 15.49(2)Å;, β = 95.64(10)°, Z = 8. The molecules are arranged in infinite zig-zag S…SnNCS…Sn&.sbnd; chains similar to those in Me3SnNCS, but with slightly longer SnN, shorter SnS bonds, and almost planar SnC3 units. Principal mean bond lengths and angles are: SnN, 2.22(5); NC, 1.17(8); CS, 1.58(7); SSn, 2.92(1); SnC, 2.09(3); CC, 1.38(2)Å; SnNCm 161(4); CSSn, 97(3); SSnN, 175(3) and CSnC, 119.8(1.5)°. 相似文献
2.
The structure of (Ph3SiN)2C has been determined by single crystal X-ray diffraction. The structure was solved by direct methods and refined to R = 0.071 for 593 independent diffractometer data. The crystals are rhombohedral, R with a = b = c 18.201(20) Å, α = β = γ = 48.82(2)°, and Z = 4. The three crystallographically independent molecules each have linear SiNCNSi chains lying along the crystallographic threefold axes; in two of the molecules the central carbon atom lies on a centre of symmetry. Principal mean bond lengths and angles are: Si, 1.696(25); SiC, 1.846(20); NC, 1.164(30); CC, 1.387(14) Å; CSi, 108.2(6); and CSiC, 110.8(6)°. 相似文献
3.
A.G. Osborne A.J. Blake R.E. Hollands R.F. Bryan S. Lockhart 《Journal of organometallic chemistry》1985,287(1):39-47
A series of [3]ferrocenophanes of general formula Fe(C5H4X)2YCl2 and the spiro compounds [Fe(C5H4X)2]2Ge (X = S, Se; Y = Ge, Sn) have been prepared by the reaction of ferrocene 1,1′-dithiol and ferrocene 1,1′-diselenol with tetrahalides of germanium and tin. Spectroscopic properties of the compounds are reported. In solution, the compounds are fluxional by a bridge reversal process. The crystal structure of 1,3-diselena-2,2-dichlorogermyl-[3]ferrocenophane at 163 K. has been determined by X-ray diffraction methods. At that temperature, crystals have space group P21/n with a 6.222(3), b 16.156(13), c 12.968(4) Å, β 97.53(1)° and Z = 4. Least-squares refinement gave R = 0.033 for 2834 unique significant reflections whose intensities were measured by counter diffractometry. The two SeGe bond lengths are 2.323 and 2.325(1) Å, with GeCl 2.148 and 2.161(1) Å. The SeGeSe bond angle is 118.2(1)°, ClGeCl 104.7(1)°, and SeGeCl angles range from 106.2 to 109.8(1)°. The SeC bond lengths are 1.901 and 1.904(5) Å, with CSeGe angles of 95.8 and 96.5(2)°. The cyclopentadienyl rings are in an eclipsed conformation with a mean twist angle of 2.7°, and are inclined to one another at 6.1°. The Se atoms are displaced from the ring planes by 0.17 and 0.20 Å yielding a non-bonded intramolecular Se…Se contact of 3.99 Å. 相似文献
4.
Bruno Crociani Guiliano Bandoli Dore A. Clemente 《Journal of organometallic chemistry》1980,184(2):269-279
The structure of the compound trans-[PdCl {(Me)N-?-C6H4OMe} (PPh3)2] was solved, using a conventional combination of Patterson and Fourier functions, least-squares refinements and electron density difference maps, to a reliability index R of 0.069 for the 2923 observed reflections collected by four-circle diffractometer. The palladium arom is surrounded in a roughly planar fashion by two trans phosphorus atoms, a chlorine atom, and a σ-bonded carbon atom of the diazabutadienyl group. This group assumes a trans configuration, the NCCN fragment being virtually planar and nearly normal to the mean coordination plane. The Pdligand bond lengths are: PdC 1.98(1), PdCl 2.41(1),PDP(1) 2.33(1) and PdP(2) 2.35(1) Å. 相似文献
5.
The title compound has been prepared by reaction of (C5H5)2Cr with oxindole (indole with CO in place of CH2 at the 2-position). Red single crystals belong to space group P21/c with a = 10.107(4) Å, b = 22.496(7) Å, c = 9.210(3) Å, β = 93.26(3)°, V = 2091(2), and Z = 2. The centrosymmetric molecule has a CrCr distance of 2.495(4) Å. The mean CrO and CrN distances for the bonds to bridging oxindolate anions are 2.024(7) and 2.065(8) Å, respectively. There is an oxindole molecule bound at each end with a CrO axial bond of length 2.341(8) Å and a hydrogen bond from the oxindole NH group to an equatorial oxygen atom of length 2.83(1) Å. The significance of this compound with respect to CrCr bonding is discussed. 相似文献
6.
The molecular structure of vinyldimethylchlorosilane has been determined by gas phase electron diffraction at room temperature. The least squares values of the bond lengths (rg) and bond angles (∠α) are : r(CH) = 1.086(6) Å, r(CC) = 1.347(5) Å, r(SiC=) = 1.838(6) Å, r(SiC) = 1.876(3) Å, r(SiCl) = 2.078(2) Å, ∠CCSi = 127.8° (1.2) and ∠=CSiCl = 107° (1). Models with pure syn form and a mixture of syn and gauche gave equally good agreement with the diffraction data. 相似文献
7.
The structural parameters of the completely relaxed 4–21G ab initio geometries of more than 30 basic organic compounds are compared to experimental results. Some ranges for systematic empirical corrections, which relate 4–21G bond distances to experimental parameters, are associated with total energy increments. In general, for the currently feasible comparisons, the following corrections can be given which relate calculated distances to experimental rg parameters and calculated angles to rs-structures For CC single bond distances, deviations between calculated and observed parameters (rg) are in the ranges of ?0.006(2) to ?0.010(2) Å for normal or unstrained hydrocarbons; ?0.011(3) to ?0.016(3) Å for cyclobutane type compounds; and +0.001(5) to +0.004(4) Å for CH3 conjugated with CO. For CO single bonds the ranges are ?0.006(9) to +0.002(3) Å for CO conjugated with CO; and ?0.019(3) to ?0.027(9) Å for aliphatic and ether compounds. A very large and exceptional discrepancy exists for the highly strained ethylene oxide, rs — re = ?0.049(5) Å and in CH3OCH3 and C2H5OCH3 the rs — re differences are ?0.029(5), ?0.040(10) and ?0.025(10) Å. Some of these discrepancies may also be due to deficiencies of the microwave substitution method caused by atomic coordinates close to inertial planes. For CN bonds, two types of NCH3 corrections are from +0.005(6) to ?0.006(6) and from ?0.009(2) to ?0.014(6) Å; and the range for NCO is +0.012(3) to +0.028(4) Å. For isolated CC double bonds the range is + 0.025(2) to +0.028(2) Å. For conjugated CC double bonds the correction is less positive (+0.014(1) Å for benzene). For CO double bonds the corrections are ?0.004(3) to +0.003(3) Å. For bond angles of type HCH, CCH, CCC, CCO, CCO, OCO, NCO and CCC the corrections are of the order of magnitude about 1–2° (or better). Angles centered at heteroatoms are less accurate than that, when hydrogen atoms are involved. Differences in HOC and NHC angles were found in a range of ?2.3(5)° to ?6.2(4)°. 相似文献
8.
Dimethylaluminium- and dimethylgallium-N,N′-dimethylacetamidine (I and II) are doubly associated forming a puckered eight-membered ring. They crystallize isostructurally in the monoclinic space group P21/c with two dimers per unit cell. The lattice constants of I are a 8.187, b 7.266, c 14.778 Å, β 103.58° and those of II a 8.163, b 7.277, c 14.835 Å, β 103.46°. The MN and the NC bond lengths within the rings are nearly equal, their mean values are for I: AlN 1.925 Å, CN 1.330 Å and for II: GaN 1.979 Å, CN 1.335 Å. This is also true for the exocyclic bond lengths with average values AlC 1.975 Å, NC 1.474 Å, CC 1.509 Å (for I) and GaC 1.998 Å, NC 1.484 Å and CC 1.507 Å (for II). The metal atoms are tetrahedrally coordinated, and the distortion is only slight. The final R-values are 0.034 and 0.056, respectively. 相似文献
9.
The copper(I) complexes [Cu(btz)2](BPh]4(I) and [Cu2(bt)4][ClO4]2 (II) have been prepared (btz = 2,2′-bi-4,5-dihydrothiazine and bt = 2,2′-bi-2-thiazoline). Crystals of (I) are orthorhombic with a = 10.927(8), b = 11.743(8), c = 15.000(6) A, Z = 2, spacegroup P21212. Crystals of (II) are monoclinic with a = 21.928(11), b = 11.925(8), c = 14.716(11) A, β = 103.6(1), Z = 8, spacegroup C2/c. 2121 and 2204 independent reflections have been measured on a diffractometer and the structures refined R 0.061 to R 0.063 respectively. In the cation of (I) the two btz ligands are coordinated via the α-di-imine groups (Cu-N 2.010(6), 2.024(6)Å). The resulting CuN4 coordination geometry is a flattened tetrahedron with a dihedral angle of 68.9° between the two “CuN2” planes. It is suggested that this distortion is an intrinsic property of the molecule associated with metal-to-ligand dπ-pπ* charge transfer rather than a consequence of lattice packing effects. In the dimeric cation (II), each copper(I) ion is bonded to the α-di-imine group of one bt molecule (A) but with appreciably different CuN bond lengths (2.277(6), 1.999(5)Å), to one nitrogen atom of a second ligand molecule (B) in the trans configuration (CuN 1.961(5)Å) and to one sulphur atom (CuS 2.428(2)Å) of a third ligand molecule (C). The coordination geometry is a very distorted tetrahedron if a very weak interaction (Cu…S 3.039(2)Å) with a sulphur atom of ligand B is discounted. It is suggested that the different structure arise from the different “bites” of the two ligands. 相似文献
10.
Crystals of [C16H36N]+[Cl3COPt]? are monoclinic, space group P21/n, with a 14.949(8), b 8.892(7), c 18.232(10) Å, β 105.5(3)°, Z 4. The structure has been refined by least-squares to a final R of 0.042 for 2358 counter intensities. The PtCl bond lengths in the square-planar anion are not significantly different (mean value 2.291 Å) and the PtC (carbonyl) bond length is 1.82 Å.Conclusions are drawn on the factors affecting the trans influence in this complex and a number of related square planar PtII chloro-complexes. 相似文献
11.
The geometrical parameters for the two conformers, gauche (g) and trans (t), of ethylamine have been determined by a joint analysis of the electron diffraction intensity measured in the present study and the rotational constants reported in the literature. The optimized geometries estimated by an SCF MO calculation with a 4-31G(N*) basis set were also used in the analysis to complement the experimental data. The bond lengths (rg) and the bond angels (rz) determined are r(CH)av = 1.107(6) Å r(CN)t = 1. 470(10)Å, r(CN)g = 1.475(10) Å r(CC)t = 1.531(6) Å r (CC)g = 1.524(6) Å , ∠CCN)t = 115.0(3)°, and ∠CCCNg = 109.7(3)°. The uncertainties represent estimated limits of error. The difference between the CCNg and CCNg angles predicted by a previous ab initio calculation is confirmed. The enthalpy difference,ΔH(gt), is determined to be 306(200) cal mol−1 using the abundance of the trans conformer, 46(10)%. 相似文献
12.
《Journal of organometallic chemistry》1987,326(3):431-436
Reactions of Rh(ClO4)(CO)(PPh3)2 with dicyano olefins, cis-NCCHCH-CH2CH2CN (c-DC1B), rans-NCCHCHCH2CH2CN (t-DC1B), trans-NCCH2CHCHCH2CN (t-DC2B), and NCCH2CH2CH2CN (DCB) produce the binuclear dicationic rhodium(I) complexes, [(CO)(PPh3)2RhNCACNRh-(PPh3)2(CO)](ClO4)2 (NCACN = c-DC1B 1), t-DC1B (2), t-DC2B (3), DCB (4). Complexes 1 and 2 are catalytically active for the hydrognation of c-DC1B and t-DC1B, respectively, to give DCB, while complex 3 catalyze the isomerization of t-DC2B to give c-DC1B and t-DC1B, and the hydrogenation of t-DC2B to DCB at 100°C. 相似文献
13.
G. Perego M. Cesari G. Del Piero A. Balducci E. Cernia 《Journal of organometallic chemistry》1975,87(1):33-41
The crystal and molecular structure of the adduct (HAlN-i-Pr)6AlH3 has been determined from single-crystal and three dimensional X-ray diffraction data collected by counter methods. The cage-type molecular structure consists of two six-membered rings, (AlN)3, joined together by four adjacent transverse AlN bonds; the loss of two of these bonds allows the complexation of one alane molecule, with five-coordination of the aluminum (trigonal bipyramidal geometry), through two AlN bonds and two AlHAl bridge bonds. The AlN bond lengths range from 1.873 to 1.959 Å; the average AlH bond length is 1.50(1) Å for the four-coordinated aluminum atoms; the average distance of the two apical hydrogens from the five-coordinated aluminum atom is 1.92(5) Å. Colourless prismatic crystals of the compound have the following crystal data: triclinic space group P; a = 17.13(2); b = 10.78(2); c = 10.20(2) Å; α = 124.3(4), β = 92.0(4), γ = 92.1(5); Z = 2; calculated density 1.157 g/cm3. The structure has been refined by block-matrix, least-squares methods using 4358 independent reflections to a standard unweighted R factor of 4.9%. 相似文献
14.
《Polyhedron》1986,5(3):845-858
The complexes M(CO)4(R′-DAB) (M = Mo or W; R′-DAB = R′NCHCHNR′; R′ = i-Pr, t-Bu, Cy or p-tol) undergo substitution of a single CO ligand by isocyanide ligands RNC (R = Me, CHMe2, CMe3, C6H11 or xylyl), in refluxing toluene to give fac-M(CO)3(CNR)(R′-DAB). Synthesis of the latter complexes can also be achieved, at ambient temperature, through the use of the nitrile complexes, Mo(CO)3(NCMe)3 and W(CO)3(NCEt)3: the method involves substitution of the nitrile ligands first by R′-DAB, then by RNC. The intermediate compounds Mo(CO)3(NCMe)(R′-DAB) and W(CO)3(NCEt)(R′-DAB) have also been isolated and characterized. Oxidation of dark blue-purple Mo(CO)3(NCMe)(t-Bu-DAB) and Mo(CO)3(CNR)(t-Bu-DAB)(R = Me or CMe3) with [Cp2Fe]PF6 in dichloromethane solution produces the paramagnetic (17-electron), orange complexes [Mo(CO)3(NCMe)(t-Bu-DAB)PF6 and [Mo(CO)3(CNR)(t-Bu-DAB)]PF6, respectively. The molybdenum cations, [Mo(CO)3(NCMe)(t-Bu-DAB)]PF6 and [Mo(CO)3(CNCMe3)(t-Bu-DAB)]PF6, react with two and one equivalent of tert-butyl isocyanide, respectively, to yield dark red cis, trans-[Mo(CO)2(CNCMe3)2)t-Bu-DAB)]PF6. Reduction of cis, trans-[Mo(CO)2(CNCMe3)2)(t-Bu-DAB)]PF6 with cobaltocene in acetone yields the analogous dark blue zerovalent species cis, trans-Mo(CO)2(CNCMe3)2(t-Bu-DAB). The compounds [Mo(CO)(CNR)4(t-Bu-DAB)](PF6)2 and Mo(CO)3(CNR)(t-Bu-DAB) are produced, via a disproportionation reaction, when solutions of the cations [Mo(CO)3(CNR)(t-Bu-DAB)]+ (R = Me or CMe3) are reacted with ∼three equivalents of RNC. On the other hand, the reaction between tert-butyl isocyanide and [Mo(CO)3(CNCMe3)(i-Pr-DAB)]+ gives seven-coordinate [Mo(CNCMe3)5(i-Pr-DAB)](PF6)2 and Mo(CO)3(CNCMe3)(i-Pr-DAB). The ligand-based reduction of the complexes M(CO)3(CNR)(R′-DAB) (M = Mo or W) is readily accessible in THF upon addition of one molar equivalent of THF-soluble LiEt3BH to yield solutions that contain the radical anions [M(CO)3(CNR)(R′-DAB)]−.. The complexes synthesized in this work have been characterized on the basis of their spectroscopic and electrochemical properties, including ESR spectral studies on the paramagnetic 17- and 19-electron complexes. 相似文献
15.
G. Perego G. Del Piero M. Cesari A. Zazzetta G. Dozzi 《Journal of organometallic chemistry》1975,87(1):53-60
The compound [(HAlN-i-Pr)2(H2AlNH-i-Pr)3] has been prepared and the crystal and molecular structure determined by an X-ray analysis, carried out with three-dimensional data collected on a diffractometer. The molecule is made up of a cyclohexane-type ring, [(HAlN-i-Pr)2(H2AlNH-i-Pr)], in skewboat conformation, on each side of which is bonded an -H2AlNH-i-Pr- bridging unit between a nitrogen atom and an aluminum atom of the ring. The molecule lies on a binary axis of the crystal, but this symmetry is fulfilled only by a statistical orientation of the asymmetric molecular units (the statistical model is not however completely defined). The AlN bond lengths range from 1.901 to 1.985 Å; the average NC bond length is 1.527(9) Å. Main crystal data are: monoclinic space group C2/c; a = 10.15(2), b = 21.64(3), c = 12.84(2) Å, β = 111.9(5)°; Z = 4; calculated density 1.095 g/cm3. The structure was solved by direct methods and block-matrix least-squares converged to an R value of 5.6%. 相似文献
16.
Walter K. Dean Gary L. Simon Paul M. Treichel Lawrence F. Dahl 《Journal of organometallic chemistry》1973,50(1):193-207
The accidental but intriguing synthesis of acetatobis(triphenylphosphine)dicarbonylmanganese(I), (CH3CO2)Mn(CO)2[P(C6H5)3]2, has been accomplished by the reaction of NaMn(CO)5 with (CH3)3SiCl followed by the addition of triphenylphosphine and acetic acid. A three-dimensional single-crystal X-ray diffraction analysis has shown an octahedral-like molecule containing a symmetrically oxygen-chelating acetate group, the first such group to be reported in a metal carbonyl complex. The two triphenylphosphine ligands occupy mutually trans positions with the two carbonyl ligands possessing the remaining cis sites in the octahedral complex. The compound crystallizes with four molecules in a monoclinic unit cell of space group symmetry and of dimensions a = 17.744(2) Å, b = 9.692(1) Å, c = 20.004(2) Å, and β = 106.195(4)°. The relatively long MnO(acetate) bond lengths [2.066(6) and 2.069(7) Å] and the relatively short MnCO bond lengths [1.701(12) and 1.760(13) Å] and the relatively short MnP(C6H5)3 bond lengths [2.260(3) and 2.275(3) Å], compared to the corresponding MnCO and MnP(C6H5)3 bond lengths in other manganese carbonyl triphenylphosphine complexes, are rationalized on the basis that the acetate ligand in this molecule functions primarily as a σ-donor. 相似文献
17.
《Journal of organometallic chemistry》1986,314(3):333-355
Bis-alkenyl complexes of the type (η-C5H5)2RH2(alkene − H)(alkyne + H) are obtained when the alkyne complex (η-C5H5)2Rh2(CO)(CF3C2CF3) is treated with the following alkenes: H2CCH2, H2CCHR (R = Me, But, Ph, CN), H2CCF2, RHCCHR′ (R = R′ = Me, Ph, Cl; R = Me, R′ = Et), cyclooctene and norbornene. An approximately equimolar amount of (η-C5H5)2Rh2(CO)2(CF3C2CF3) is also formed. The reactions are greatly accelerated when the reaction mixtures are exposed to sunlight. There is some regioselectivity in the reactions with H2CCHR and MeHCCHet, with a preference for CH bond cleavage at the least crowded alkene-carbon. When the reaction with acrylonitrile is performed in the absence of sunlight, the complex (η-C5H5)2(CO){(H2CCHCN)(CF3C2CF3)} can be isolated; upon exposure to sunlight, there is loss of CO and H-transfer to form two isomers of the appropriate bis-alkenyl complex.The molecular geometries of (η-C5H5)2Rh2(CHCHCN){C(CF3)C(CF3)H} and (η-C5H5)2Rh2(CHCF2){C(CF3)C(CF3)H} have been ascertained by X-ray structure determination. Each molecule has two bridging alkenyl units spanning a RhRh single bond; the dihedral angle between the two RhRhCC planes is just above 90°. There is a cyclopentadienyl ring η5-attached to each metal. Crystal data: C17H13F6NRh2·H2O, M 569.1, monoclinic, P21/n, a 15.014(7), b 14.882(7), c 8.590(5) Å, β 94.57(9)°, Z = 4, final R 0.056 for 2493 observed reflections; C16H12F8Rh2, M 562.1, monoclinic, P21/c, a 13.037(6), b 8.765(2), c 14.873(3) Å, β 103.16(3)°, Z = 4, final R 0.062 for 1820 observed reflections. 相似文献
18.
The synthesis of a new class of two-dimensional triazole compounds is described, including the crystal structure of [Co(NCS)2(btr)2]H2O [btr stands for 4,4′-bis-1,2,4-triazole (C4H4N6)]. Crystals are monoclinic, space group C2/c, a = 11.159(1) Å, b = 13.047(4) Å, c = 12.993(3) Å, β = 91.81(2)°, Z = 4. The structure has been solved by Fourier and direct methods and refined by full-matrix least squares to R = 0.0229, Rw = 0.0283. The structure consists of layers of six-coordinated cobalt atoms, each having two trans-oriented N-bonded thiocyanate groups [CoNCS 2.098(2) Å] and linked together in the equatorial plane by single bridges of btr to a two-dimensional network. The btr ligand coordinates through its N(1) and N(1′) atoms [CoN 2.128(1) and 2.142(1) Å]. The intralayer CoCo distance is 9.207(2) Å, and the inter-layer CoCo distance is 8.584(1) Å. The magnetic susceptibilities of the compound and of the isostructural nickel and iron compounds are discussed. The iron compound exhibits a high-spin-low-spin crossover at liquid-nitrogen temperatures, as shown by magnetic susceptibility. 相似文献
19.
Masaaki Ichinohe Kaori Sanuki Shigeyoshi Inoue Akira Sekiguchi 《Silicon Chemistry》2007,3(3-4):111-116
The reaction of dilithiosilane, ( t Bu2MeSi)2SiLi2 (2), with 1,1,2,2-tetrachloro-1,2-dimesityldisilane produced the tetrasila-1,3-butadiene derivative, ( t Bu2MeSi)2Si=Si(Mes)–(Mes)Si=Si(SiMe t Bu2)2 (3, Mes = 2,4,6-trimethyl-phenyl), which was isolated as reddish-purple crystals. The structure of 3 was determined by both spectroscopic and crystallographic methods; the Si=Si double bond lengths are 2.2003(12) and 2.1983(12) Å, and the length of the central Si?Si single bond is 2.3376(11) Å. The tetrasilabutadiene moiety is highly twisted, the torsional angle of Si1=Si2?Si3=Si4 being 72°. The reaction of 3 with t BuLi or KC8 in THF gave the disilenyllithium 4 and disilenylpotassium 5, which contain an sp 2-type silyl anion, by the reductive cleavage of the central Si–Si bond in 3. 相似文献
20.
The structural changes, which occur in the amide unit when the NH2-group is twisted out of plane by rotation about the NC bond, have been determined by comparing the completely relaxed ab initio geometries of planar and perpendicular formamide and acetamide. In the perpendicular conformation, in which the π-electron amide resonance is uncoupled, the NC bond distance is 0.080.09 Å longer than in the planar form; the CO bond distance is about 0.01 Å shorter; NH distances are about 0.01 Å longer; and HNC angles are 510° smaller, whereas the CNO angle is relatively constant. Because of the apparent invariance of CH3-hyperconjugation effects in planar and perpendicular acetamide, it is tentatively postulated that anomeric orbital interactive effects (involving the lone pair on NH, the CO π-electron pair and antibonding π*-group-orbitals on C(α) in NHC(HR)C(O)), which should be an important factor in determining peptide chain conformation, do not vary significantly with small deviations from amide group planarity. 相似文献