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1.
The molecular structure of the title compounds have been investigated by gas-phase electron diffraction. Both molecules exist as about equal amounts of the two gauche conformers. There is no evidence for the presence of a syn conformer, but small amounts of this form cannot be excluded. Some of the important distance (ra) and angle (∠α) parameters for 1,1-dichloro-2-bromomethyl-cyclopropane are: r(CH) = 1.095(19) Å, r(C1C2) = 1.476(11) Å, r(C2C3) = 1.517(31) Å, r(CCH2Br) = 1.543(32) Å, r(CCl) = 1.752(6) Å, r(CBr) = 1.950(13) Å, ∠CCBr = 110.5(1.9)°, ∠ClCCl = 111.9(6)°, ∠CCC = 117.5(1.3)°, σ1 (CC torsion angle between CBr and the three-membered ring for gauche-1) = 116.2(5.6)°, σ2 = −132.7(7.6). For 1,1-dichloro-2-cyanomethyl-cyclopropane the parameter values are: r(CH) = 1.101(16) Å, r(C1C2) = 1.498(9) Å, r(C2C3) = 1.544(21) Å, r(C2C4) = 1.497(33) Å, r(CCN) = 1.466(26) Å, r(CN) = 1.165(8) Å, r(CCl) = 1.754(5) Å, ∠CCCN = 113.7(2.0)°, ∠CCC = 122.8(1.6)°, ClCCl = 112.5(4)°, σ1 = 113(13)°, σ2 = −124(10)°. 相似文献
2.
Richard D. Adams F.Albert Cotton Bertram A. Frenz 《Journal of organometallic chemistry》1974,73(1):93-101
One of the main products of oxidation of (η5-C5-H5)2Fe2(CO)3Ge(CH3)2 by air has been shown to be [(η5-C5H5)(CO)2FeGe(CH3)2]2O. The infrared, NMR and mass spectra are consistent with this formula and the detailed structure has been established by X-ray crystallography. In polar solvents the NMR suggests the existence of major and minor conformers interconverting only slowly on the NMR time scale at ≈ 25°. The X-ray diffraction study has shown the compound to consist of two (η5-C5H5)(CO)2FeGe(CH3)2 moieties joined by a bridging oxygen atom. Two rotational isomers are present in the unit cell in a disordered fashion. Some pertinent average distances and angles are: FeGe, 2.372 Å; GeO, 1.785 Å; GeOGe′, 134°. The compound crystallizes in the monoclinic system, space group P21/n, with a 8.056(2), b 12.506(2), c 22.631(3) Å, β 98.01(1)°, dcalc 1.692 g cm?3. Counter data were collected using Mo-Kα radiation. The 1780 reflections above background were used in least-squares refinement which converged at R1 = 0.051 and R2 = 0.068. 相似文献
3.
H. Lumbroso C. Liégeois G.C. Pappalardo A. Grassi 《Journal of Molecular Structure》1982,87(3):229-236
From the ab initio molecular energies of the possible conformers and from a classical dipole moment analysis of 2-oxopyrrolidin-1-ylacetamide (υ = 4.02 D in dioxan at 30.0°C), the preferred conformation in solution of this novel nootropic agent has been determined. The exocyclic NCH2 bond is rotated in one sense by 90° and the exocyclic CH2C bond rotated in the same sense by 120° from the “planar” (OO)-cis conformation. The structures of the two enantiomers in solution differ from that of the crystalline molecule. 相似文献
4.
Kunio Miki Masahiro Yama Yasushi Kai Nobutami Kasai 《Journal of organometallic chemistry》1982,239(2):417-428
The molecular structure of a three-coordinate palladium(II)-styrene complex, [Pd(η5-C5H5)(PEt3)(styrene)]BF4 has been determined by means of X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c, with four formula units in a cell of dimensions: a 10.229(3), b 11.262(3), c 18.760(5) Å and β 103.77(2)°. The structure was solved by the heavy atom method, and refined by the least-squares procedure to R = 0.050 for 3635 observed reflections. The palladium atom is surrounded by the cyclopentadienyl group, the triethylphosphine ligand and the olefinic bond of styrene in the cationic complex. In the palladiumstyrene bonding, the olefinic bond is inclined by 77.3° to the coordination plane defined by the Pd and P atoms and the center of the cyclopentadienyl ring (PdC(1) 2.176(6), PdC(2) 2.234(5) and C(1)C(2) 1.369(8) Å). 相似文献
5.
B. Cetinkaya P.B. Hitchcock M.F. Lappert S. Torroni J.L. Atwood W.E. Hunter M.J. Zaworotko 《Journal of organometallic chemistry》1980,188(3):C31-C35
The 2,6-di-t-butyl-4-methylphenoxo ligand (ArO?) is ambidentate, giving rise to the O-bonded 15-electron d1 [Ti(η-C5H5)2OAr] and the η5 -[C(2)-C(6)]-bonded 18-electron d8 complex [Rh(ArO-η5)(PPh3)2], obtained from [{Ti(η-C5H5)2Cl}2]-LiO Ar and [Rh{N(SiMe3)2}(PPh3)2]-ArOH, respectively; the average TiC(η) distance is 2.362(10) Å, TiO 1.892(2) Å, and O:C(of Ar) 1.352(3) Å, and TiOC 142.3(2)°; in the RhI complex, C(2)C(6) are coplanar (with CC(av.) 1.38(2) Å). C(1)O 1.28 Å, and Rh to C(2) C(6) bond lengthsare in the range 2.19–2.65 Å. 相似文献
6.
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
7.
John J. Eisch Robert J. Manfre David A. Komar 《Journal of organometallic chemistry》1978,159(4):C13-C19
A 1:1 combination of dichloro(bis-η5-cyclopentadienyl)titanium and alkyl-aluminum halide in methylene chloride solution effects the regiospecific alkylation of alkynyl(trimethyl)silanes in 60–95% yields. With RCCSiMe3 substrates, where Rsaturated alkyl group, the carbometallation (introduction of a methyl or an ethyl group) occurs regiospecifically and stereoselectively in a - manner, giving a 75:25 to a 90:10 ratio of isomers. When the R in RCCSiMe3 is phenyl or 1-cyclohexenyl, then a non-stereoselective carbometallation is observed (50:50 mixtures of isomers). These results, which are explicable in terms of the formation of the (C5H5)2Ti-R cation and its attack on the alkynylsilane, offer stereochemical evidence for a cationic initiating step in the polymerization of ethylene by homogeneous Ziegler-Natta catalysts. 相似文献
8.
The syntheses of P[CCCF3]3, As[CC CF3]3, and Sb[CCCF3]3 are reported. The compounds are colorless and volatile, with melting points of ?20° to ?25°, 23–24°, and 55–56°C, respectively. The mass spectra show the molecular ion of each compound. The rearrangement ion [F3CCCCCCF2]+] gives the strongest peak in each spectrum. 相似文献
9.
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
10.
A.A. Pasynskii I.L. Eremenko Yu.V. Rakitin V.M. Novotortsev V.T. Kalinnikov G.G. Aleksandrov Yu.T. Struchkov 《Journal of organometallic chemistry》1979,165(1):57-64
The binuclear complex (C5H5)2Cr2(S)(SCMe3)2 was prepared by refluxing a solution of chromocene and t-butylmercaptane in heptane. The structure of the product was determined by single crystal X-ray diffraction. The chronium atoms are linked by a sulphide bridge (SCr 2.24 Å;, <CrSCr 74.1° and two SCMe3 bridges (CrS 2.38 Å;, <CrSCr 68.3–69.3°). The two cyclopentadienyl ligands (CC 1.41 Å;, CrC 2.23 Å;) are in apical positions, their ring planes being parallel to each other. The complex is an antiferromagnet (?2J cm?1) despite the small CrSCr angles and short chromiumchromium distance (2.689 Å;) indicative of strong CrCr bonding. 相似文献
11.
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
12.
Kunio Miki Yasushi Kai Noritake Yasuoka Nobutami Kasai 《Journal of organometallic chemistry》1977,135(1):53-64
The molecular structure of [PdCl(CH2SCH3)(PPh3)] has been determined from three-dimensional X-ray diffraction data collected at both ?160 and 20°C. The crystal belongs to the monoclinic system, space group P21/c, with four formula units in a cell of dimensions: a 11.398(2), b 9.788(1), c 17.267(2) Å and β 95.38(1)° at ?160°C; a 11.454(3), b 9.880(2), c 17.459(2) Å and β 95.84(1)° at 20°C. The structure was solved by the conventional heavy atom method, and refined by the least-squares procedure to R = 0.049 (?160°C) and 0.068 (20°C) for observed reflections. No essential difference is observed between molecular structures at ?160 and 20°C. The geometry around the palladium atom is square-planar. The CH2SCH3 group, bonded to the palladium atom through PdC and PdS bonds, forms a metallocyclic three-membered ring [PdC(1) 2.042(6), PdS 2.371(1), SC(1) 1.756(6) and SC(2) 1.807(7) Å, PdC(1)S 76.9(2), PdC(1)H 113(3) and 122(4)°, SC(1)H 115(3) and 112(4) and HC(1)H 113(5)° at ?160°C]. 相似文献
13.
The structure of Mn(NO)3PPh3 has been analyzed by single-crystal X-ray diffraction. It shows a tetrahedral geometry with essentially linear nitrosyl groups, and an eclipsed configuration around the MnP bond. Average distances and angles are: MnN 1.686(7) Å, MnP 2.315(2) Å, NO 1.165(10) Å, PC 1.815(4) Å, MnNO 177.2(7)°, PMnN 103.6(2)°, NMnN 114.7(4)°. Final R factor 7.3% for 2064 non-zero reflections. The structure of the five-coordinate nitrito complex Mn(NO)2(ONO)(PEt3)2 is also mentioned briefly. 相似文献
14.
《Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy》1994,50(6):1015-1022
A uridine specifically deuterated on the deoxyribose ring at the C2′, and the same compound in a more rigid form, due to a chemically fused ring (between C3′ and C5′), have been synthesized. By NMR, the coupling constants J1′-2′ and J3′-4′ have been determined and the populations of the C2′-endo and C3′-endo conformers have been deduced for the two compounds. Comparison of these results with an FTIR and Raman study of the stretching mode νCD on the C2′ site allows a specific assignment of each observed band to one of the two classes of conformers. This enables us to consider the further step: the direct recognition, by IR and Raman spectroscopies, of the local conformation at a specific site of a synthetic oligonucleotide, using the νCD signals as marker bands. 相似文献
15.
The crystal and molecular structure of hexaphenylditin selenide (C6H5)3SnSeSn(G6H5)3 was determined by X-ray diffraction data and was refined to R 0.055. The compound is monoclinic, space group P21, with a 9.950(4), b 18.650(7), c 18.066(6) Å, β 106.81(4)°, Z 4. The two molecules in the asymmetric unit differ slightly in their conformations, both having approximate C2 symmetry. Bond lengths and angles are: SnSe 2.526 (2.521(3) ? 2.538(3)) Å; SnC 2.138 (2.107(16)?2.168(19)) Å; SnSeSn 103.4(1)°, 105.2(1)°. There are only slight angular distortions at the SnSeC3 tetrahedra (SeSnC angles: 104.3(5)?114.8(4)°). The bond data indicate essentially single bonds around the Sn atoms. 相似文献
16.
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
17.
Crystal and molecular structure of tricyclopentadienyltetrahydrofuranuranium(III), (η5-C5H5)3U·OC4H8
H.J. Wasserman A.J. Zozulin D.C. Moody R.R. Ryan K.V. Salazar 《Journal of organometallic chemistry》1983,254(3):305-311
Tricyclopentadienyltetrahydrofuranuranium(III), (η5-C5H5)3U·OC4H8, crystallizes in the centrosymmetric monoclinic space group P21/n with a 8.248(3), b 24.322(17), c 8.357(4) Å, β 101.29(5)°, V 1644.0 Å3 and ρ(calc) 2.04 g cm?1 for Z = 4 and mol.wt. 595.0. Diffraction data (Mo-Kα, 2θ(max) 45°) were collected on an Enraf-Nonius CAD4 diffractometer and the structure was refined to Rw(F) 4.7% for those 1530 reflections having I > 2σ(I). The molecule consists of a distorted tetrahedral arrangement of THF and (η5-C5H5) ligands with CpUCp angles in the range 110.4–122.4° and CpUO angles between 90.2 and 106.0°. Individual uranium-carbon distances range from 2.76(2) to 2.82(2) Å and average 2.79[1] Å. The uranium-oxygen distance of 2.551(10) Å suggests a 10-coordinate U3+ radius of 1.20 Å in this class of compounds. 相似文献
18.
《Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy》1986,42(5):599-602
The presence of conformers and corresponding OH rotamers in benzylalcohol and nine related compounds, dissolved in CCl4 and CS2, was studied by means of the i.r. OH stretching band. It is demonstrated that in the benzyalcohols at least two conformers are present differing in the position of the CO bond with regard to the plane of the ring, viz. at torsion angles ω of 0° and approximately 60°. The existence of a third conformation with ω = 90° cannot be excluded. The presence of different OH rotamers appears to be affected by the strength of the OH … π interaction. Effects on the distribution of conformers could not be proved. 相似文献
19.
A.B. Zolotoy O.A. Dyachenko L.O. Atovmyan I.P. Yakovlev V.O. Reichsfeld 《Journal of organometallic chemistry》1980,190(3):267-276
The structure of 5-ethyl-5,10-dihydro-10,10-diphenylphenazasiline has been determined from three-dimensional X-ray data collected by counter methods. The compound in the monoclinic space group P21/b with a 10.782(5), b 22.642(9), c 8.830(4) Å and γ 74°41′(2). The observed and calculated densities (Z = 4) are 1.22 and 1.21 g cm-3, respectively. Anisotropic(Si, N, C)-isotropic block-diagonal least squares refinement gave a conventional R factor of 3.9% for 1871 reflections with I>2σ(I). The central six-membered ring of the tricyclic system adopts a boat conformation; the dihedral angle between the benzo-group planes is 157.3°. The CSiC angle in the heterocycle is 101.1(1)°; the mean SiC bond length is 1.850(2) Å (in the cycle) and 1.862(2) Å (with Ph group). The nitrogen atom is displaced 0.05 Å from the plane of the adjacent carbon atoms; the sum of the angle about N is 359.7°. 相似文献
20.
R. A. Jackson 《Journal of organometallic chemistry》1975,90(3):C52-C54
The linkage isomers CpM(CO)nSCN and CpM(CO)nNCS (Cp = η-C5H5; M = Fe, n = 2; M = Mo, n = 3) are interconverted by 366 nm irradiation in tetrahydrofuran solution at 30°C. Molybdenum and tungsten halide complexes CpM(CO)2-(PPh3)X undergo cistrans isomerization and disproportionation to CpM(CO)(PPh3)2X and CpM(CO)(PPh3)2X under similar conditions (benzene solution). 相似文献