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1.
The equilibrium structures, binding energies, and vibrational spectra of the clusters CH3F(HF)1 n 3 and CH2F2(HF)1 n 3 have been investigated with the aid of large-scale ab initio calculations performed at the Møller–Plesset second-order level. In all complexes, a strong C–FH–F halogen–hydrogen bond is formed. For the cases n = 2 and n = 3, blue-shifting C–HF–H hydrogen bonds are formed additionally. Blue shifts are, however, encountered for all C–H stretching vibrations of the fluoromethanes in all complexes, whether they take part in a hydrogen bond or not, in particular also for n = 1. For the case n = 3, blue shifts of the ν(C–H) stretching vibrational modes larger than 50 cm−1 are predicted. As with the previously treated case of CHF3(HF)1 n 3 complexes (A. Karpfen, E. S. Kryachko, J. Phys. Chem. A 107 (2003) 9724), the typical blue-shifting properties are to a large degree determined by the presence of a strong C–FH–F halogen–hydrogen bond. Therefore, the term blue-shifted appears more appropriate for this class of complexes. Stretching the C–F bond of a fluoromethane by forming a halogen–hydrogen bond causes a shortening of all C–H bonds. The shortening of the C–H bonds is proportional to the stretching of the C–F bond.  相似文献   

2.
The title compounds, which contain six-membered chelate rings locked in the chair conformation, have been prepared by the reaction of (C6H5)3P with the appropriate tetracarbonyl derivative in refluxing mesitylene.  相似文献   

3.
Asymmetric ditertiary stibine sulfides (C6H5)(CH3)(S)SbCH2Sb(CH3)(C6H5) and [(C6H5)(CH3)(S)Sb]2(CH2)3 have been prepared. It was found that they exist as only one of two possible diastereomers in the crystalline state. However, isomerization to the other form takes place in solution, resulting in an equilibrium mixture. A possibility of configurational lability of tertiary stibine sulfide was suggested for the first time.  相似文献   

4.
The thermal behaviour and some relationships between the physical properties and structure of complexes of general formula (n-CnH2n+1NH2)2CuCl2, with n = 10, 12, ? 18, have been investigated by DSC and X-ray powder diffraction techniques. The high enthalpy solid—solid phase transitions observed for the complexes in the temperature range 350–390 K could be associated with the disordering of the hydrocarbon regions of the structure, as already observed for other similar layer compounds.  相似文献   

5.
The complex [Ag(DDM)2(CH3C6H4NH2)]NO3, where DDM is 4,4-diaminodiphenylmethane [CH2(C6H4NH2)2], was synthesized and its structure was determined. The crystals are monoclinic, space group P21/n, a = 9.543(2) ?, b = 18.056(4) ?, c = 1.901(2) ?, β = 106.94(3)°, V = 1796.8(6) ?3, ρcalcd = 1.443 g/cm3, Z = 4. The Ag atom (at the inversion center) is coordinated at the vertices of an almost undistorted octahedron by six nitrogen atoms of the primary amino groups from four bridging DDM molecules and two terminal p-toluidine molecules (Ag-N, 2.546(3) ?; NAgN, 89.7–90.3°). Wavelike layers composed of conjugate multiunit metal rings, each containing four Ag+ ions and four bridging DDM ligands, are formed in the structure in the [101] direction (a 2D polymer). Uncoordinated NO 3 anions are arranged in the cavities between the layers and link them by N-H⋯O hydrogen bonds. Original Russian Text ? Yu.V. Kokunov, V.V. Kovalev, Yu.E. Gorbunova, 2007, published in Zhurnal Neorganicheskoi Khimii, 2007, Vol. 52, No. 12, pp. 1992–1998.  相似文献   

6.
The thermal decomposition of the complexes trans-[Pt(X)(CH3)L2] (L  P(C2H5)3; X  Cl, Br, I, CN) in decalin at 170 and 200°C affords methane platinum metal and [Pt(X)2L2]. The kinetics of the decomposition of the complexes were determined by monitoring the appearance of methane by GLC. The observed first-order rate constant was found to be independent on the nature of the ligand X. The thermal decomposition of the trideuteriomethyl complexes [Pt(X)(CD3)L2] (X  I, CN) in decalin-d18 at 170 and 200°C was studied by GLC/MS. The thermolysis affords CD3H and CD4 in ratios which are independent of the nature of X and of the temperature used. The mass spectra of the complexes were also examined. A relative scale of platinum-to-methyl bond dissociation energies has been established by measuring the appearance potential of the fragment ion [Pt(X)L2]+ and the ionization energies in the series [Pt(X)(CH3)L2]. Ionization potentials and PtCH3 bond energies show a clear dependence on the nature of X which is not reflected in corresponding changes in the decomposition rates.  相似文献   

7.
The electron donating water soluble phosphines, P{(CH2)nC6H4-p-SO3Na}3,n = 1, 2, 3 and 6, react rapidly with Co2(CO)8 under two phase reaction conditions to yield the disproportionation products, [Co(CO)3(P{(CH2)nC6H4-p-SO3Na3}2] [Co(CO)4]. Selective precipitation yields the formally zwitterionic complex anions as the sodium salt, [Co(CO)3(P{(CH2)nC6H4-p-SO3} 3)2]5−. The anions can be used as precursors to water soluble cobalt hydroformylation catalysts under two phase and supported aqueous phase conditions. The tendency to form alcohol products is low with these complexes. The behavior of the catalysts is consistent with an active species that remains water soluble during the reaction and is not leached into the nonaqueous phase.  相似文献   

8.
Mixed-ligand complexes CdPhen(i-BuOCS2)2 (I) and CdPhen(n-BuOCS2)2 (II) have been synthesized. Their structures were solved using X-ray diffraction data (X8 APEX diffractometer, MoK α radiation, 1641 and 2497 F hkl , R = 0.0359 and 0.0389). Crystals I are orthorhombic with unit cell parameters a = 6.5883(3) Å, b = 19.7123(10) Å, c = 20.1936(11) Å, V = 2622.6(2) Å3; Z = 4, space group Pbcn; crystals II are monoclinic, a = 6.5845(2) Å, b = 19.1522(6) Å, c = 20.7091(7) Å, β = 97.106(1), V = 2591.5(1) Å3, Z = 4, space group C2/c. The structures consist of discrete mononuclear molecules in which the coordination polyhedron of the Cd atom is a distorted N2S4 octahedron. Molecular packing and interactions in the structures are discussed. Original Russian Text Copyright ? 2007 by R. F. Klevtsova, T. G. Leonova, L. A. Glinskaya, and S. V. Larionov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 48, No. 2, pp. 274–281, March–April, 2007.  相似文献   

9.
The P-functional organotin dichloride [Ph2P(CH2)3]2SnCl2 (3) is synthesized by reaction of Ph2P(CH2)3MgCl with SnCl4 independently of the molar ratio of the starting compounds. The corresponding organotin trichlorides Ph2P(CH2)nSnCl2R (4: n=2, R=Cl; 5: n=3, R=Cl; 6: n=3, R=Me) are formed in a cleavage reaction of Ph2P(CH2)nSnCy3 (n=2, 3) with SnCl4 or MeSnCl3, respectively. The main features of the crystal structures of 3–6 are both intra- and intermolecular PSn coordinations and the existence of intermolecular Sn---ClSn bridges. For further characterization of the title compounds, the adducts 4(Ph3PO)2 (7) and 5(Ph3PO) (8), as well as the P-oxides and P-sulfides of 3–6 (9–15), are synthesized. The results of crystal structure analyses of 7, 11, 12, and 14 are reported. The structures of 9–15 are characterized by intramolecular P=XSn interactions (X=O, S). A first insight into the structural behavior of the compounds 3–15 in solution is discussed on the basis of multinuclear NMR data.  相似文献   

10.
The stabilities of simple and internally coordinated organozinc-transition metal compounds towards disproportionation have been investigated by the microwave titration technique. Simple alkyl- and aryl-derivatives disproportionate to such an extent as to preclude isolation. Internal coordination was found to stabilize the asymmetric compounds, and several derivatives containing the dimethylaminopropyl group were isolated. The crystal structure of one of them, Me2N(CH2)3-ZnW(Cp)(CO)3, was determined by a single-crystal X-ray study. The crystals are orthorhombic, space group P212121, with four molecular units in a cell with parameters a 8.406(1), b 12.179(2) and c 16.642(2) Å. The structure was solved by standard Patterson and Fourier techniques. The refinement, with anisotropic temperature factors for the two heavy atoms, converged at RF = 0.092 (RwF = 0.089) for 1536 observed reflections with I>2.5σ(I). The molecule consists of a central tungsten atom, surrounded in a tetragonal pyramidal fashion by a cyclopentadienyl group in the apical position and three carbon monoxyde molecules and a zinc atom occupying the basal positions. The zinc atom is three-coordinate, being surrounded by the tungsten atom and the chelating dimethylaminopropyl group; there is, however, a short intermolecular contact between zinc and a carbonyl oxygen atom at 2.61(3) Å.  相似文献   

11.
Powder X-ray diffraction, 119Sn NMR spectra, and 1H NMR spin–lattice relaxation times, T1, were measured for (CH3)nNH4−nSnCl3 (n=1–4). From the Rietveld analysis, it is shown that all four compounds crystallize into deformed perovskite-type structures at room temperature. The temperature dependence of 1H T1 was analyzed in terms of the CH3 reorientation and other motions of the whole cation. Except for the phase transition in CH3NH3SnCl3, which is from monoclinic to rhombohedral at 331 K, 1H T1 was continuously changed at other phase transitions in this compound as well as in the n=2–4 compounds, suggesting that the transitions are not caused by the change of the motional state of the cation but by an instability of the [SnCl3]nn perovskite lattice.  相似文献   

12.
咸春颖  林苗 《无机化学学报》2003,19(9):1030-1032
The new complex [Ce(CH2=C(CH3)COO)2(NO3)(Phen)]2 was prepared in ethanol-aqueous solution with 8-hydroxyquinoline as the acidity regulator. Its crystal structure was determined by X-ray diffraction analysis. The title complex is triclinic, space group P1, a=1.00832(3)nm, b=1.02858(8)nm, c=1.12350(8)nm, α=113.9250(10)°, β=103.8210(10)°, γ=81.4650(10)°, V=1.03252(14)nm3, Z=1, Dc=1.700g·cm-3, F(000)=522. The coordination number of Ce3+ is nine. CCDC: 211278.  相似文献   

13.
氧化双[三(2-甲基-2-苯基)丙基]锡分别与庚二酸和辛二酸反应, 合成了2个双[三(2-甲基-2-苯基)丙基锡]二元酸酯(CH2)n[CO2Sn(CH2CMe2Ph)3]2[(n=5 (1), 6 (2)], 经IR、1H和13C NMR、元素分析和X射线单晶衍射对化合物进行了表征。化合物属单斜晶系, 空间群为P21/c。锡原子均为畸型四面体构型, 化合物1以氢键作用形成一维链状结构, 化合物2以氢键和C-H…π作用形成二维网状结构。化合物12在340 ℃以下具有良好的热稳定性, 对人癌细胞Colo205、HepG2、MCF-7、Hela、NCI-H460均具有较好的体外抑制活性, 且具有一定的抑菌活性。  相似文献   

14.
氧化双[三(2-甲基-2-苯基)丙基]锡分别与庚二酸和辛二酸反应, 合成了2个双[三(2-甲基-2-苯基)丙基锡]二元酸酯(CH2)n[CO2Sn(CH2CMe2Ph)3]2[(n=5 (1), 6 (2)], 经IR、1H和13C NMR、元素分析和X射线单晶衍射对化合物进行了表征。化合物属单斜晶系, 空间群为P21/c。锡原子均为畸型四面体构型, 化合物1以氢键作用形成一维链状结构, 化合物2以氢键和C-H…π作用形成二维网状结构。化合物12在340 ℃以下具有良好的热稳定性, 对人癌细胞Colo205、HepG2、MCF-7、Hela、NCI-H460均具有较好的体外抑制活性, 且具有一定的抑菌活性。  相似文献   

15.
The reaction of n-butyllithium chelated to N,N,N′,N′-tetramethylethylenediamine (TMEDA) with acenaphthene results in 1,2-hydrogen abstraction to give the dilithio complex of acenaphthylene, [Li(CH3)2N(CH2)2N(CH3)2]2[C12H8]. This compound was isolated as a crystalline product and characterized by single crystal X-ray crystallography. [Li(CH3)2N(CH2)2N(CH3)2]2[C12H8] crystallizes with a unit cell of a = 23.164(10), b = 25.609(10) and c = 8.495(6) Å in the orthorhombice space group Fdd2. The calculated density is 1.04 g cm?3 for 8 molecules per unit cell. The observed density is 1.03(4) g cm?3. 1412 unique reflections were measured on a full circle X-ray diffractometer. The light atom, acentric structure was solved by the symbolic addition technique and refined by full matrix least squares to R1 = 0.058 and R2 = 0.056.The acenaphthylene fragment is nearly planar. The effect of charge transfer is evidenced in the short C(3)C(4) bond distance of 1.30(3) Å and the lengthening of the C(1)C(2) bond length from the localized olefinic bond distance of 1.34 to 1.42(2) Å. The two LiTMEDA fragments are coordinated to both sides of the five membered carbon atom ring of the acenaphthylene group.  相似文献   

16.
Syntheses and single-crystal X-ray diffraction studies have been completed on two cycloruthenapentadienyl (CO)6Ru2L2 derivatives, with L = CH2OHC = CCH2OH and C2H5C=CCH2CH2OH respectively. Crystal data are as follows: for [(CO)3RuC4(CH2OH)4]Ru(CO)3·H2O, P21/c, a 13.72(1), b 9.501(4), c 14.86(1) Å, β 101.10(6)°, Rw = 0.052 for 1911 reflections; for [(CO)3RuC4(CH2CH2OH)2(C2H5)2]Ru(CO)3, P21/c, a 9.191(3), b 16.732(4), c 14.903(3) Å, β 113.61(4)°, Rw = 0.042 for 2865 reflections. Both compounds are built up from binuclear units, each unit being regarded as a Ru(CO)3 fragment π-bonded to a cycloruthenapentadienyl ring. The molecular parameters are compared with those of known cyclometallapentadienyl complexes of transition metals. The presence of a semi-bridging CO group is discussed.  相似文献   

17.
Three families of heterobimetallic compounds were obtained by reaction of [Mo(CO)3(CH3CN)2(Cl)(SnRCl2)] (R = Ph, Me) with P(4-XC6H4)3 (X = Cl, F, H, Me, MeO). The type of compound obtained dependent on the solvent and concentration of the starting compound. So, [Mo(CO)2(CH3COCH3)2(PPh3)(Cl)(SnRCl2)]·nCH3COCH3 (R = Ph, n = 0.5; R = Me, n = 1) (type I) and [Mo(CO)3{P(4-XC6H4)3}(μ-Cl)(SnRCl2)]2 (R = Ph, X = Cl, F, H, Me, MeO; R = Me, X = Cl, F) (type II) were isolated from acetone solution in ca 0.05 M and 0.1 M concentrations, respectively. However, [Mo(CO)3(CH3CN) {P(4-XC6H4)3}(Cl)(SnRCl2)] (R = Ph, X = H; R = Me, X = Cl, F, H) (type III) were obtained from dichloromethane solution independently of the concentration used. All new complexes showed a seven-coordinate environment at molybdenum, containing Mo---Cl and Mo---Sn bonds. Mössbauer spectra indicated a four-coordination at tin for type III complexes.  相似文献   

18.
The trimeric, cyclic dimethyltin-containing tungstophophate [{(Sn(CH3)2)(Sn(CH3)2O)(A-PW9O34)}3]21− (1) has been synthesized in aqueous acidic medium and characterized by IR, elemental analysis, electrochemistry, and FT-ICR MS. Single-crystal X-ray analysis was carried out on Cs12Na9[{(Sn(CH3)2)(Sn(CH3)2O)(A-PW9O34)}3]·20H2O (1a), which crystallizes in the trigonal system, space group R3, with a = b = 29.7445(7) ?, c = 15.5915(7) ? and Z = 3. Polyanion 1 is composed of three trilacunary (A-PW9O34) Keggin fragments that are linked on one side via three isolated dimethyltin groups and on the other side by a (Sn3(CH3)6O3) unit and three cesium ions, resulting in a cyclic assembly with C 3v symmetry. The discrete molecular, hybrid organic–inorganic 1 was synthesized by reaction of (CH3)2SnCl2 with Na9[A-PW9O34] in 0.5 M sodium acetate buffer (pH 4.8). Comparison of several characteristics of the cyclic voltammograms of 1 and (A-PW9O34)9−, including the potential location of their reduction peaks, the difference in their current intensities and their qualitative relative electron transfer speeds, supports the conclusion that the solid-state structure of 1 is retained in solution. The presence of (PW9O34)-based species in solutions of 1 was also confirmed by FT-ICR mass spectrometry. Dedicated to Professor Günter Schmid on the occasion of his 70th birthday.  相似文献   

19.
丁二酸、戊二酸和己二酸分别与μ-氧-双[三(2-甲基-2-苯基)丙基]锡反应,合成了3个二[三(2-甲基-2-苯基)丙基锡]二元酸酯(CH2)n[CO2Sn(CH2CMe2Ph)3]2(n=2(1),3(2),4(3))。对化合物1~3进行了元素分析、红外光谱及核磁共振(1H,13C)表征,并通过X-射线晶体衍射分析测定晶体结构。化合物中锡与配基原子构成畸型四面体构型。试验表明,化合物23均对人癌细胞Colo205、HepG2、MCF-7、Hela、NCI-H460的增殖具有较强的抑制作用。  相似文献   

20.
The NIR and IR transmission spectra at room temperature of single crystals of (C2H5NH3)2PdCl4 (EAPdC) have been measured, as well as unpolarized Raman spectra at room and liquid-nitrogen temperature. These vibration spectra are compared with those of EACuC and EACdC. We conclude that EAPdC belongs to the family of compounds EAMC, where M = Mn, Cu, Cd.  相似文献   

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