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1.
The structures and isomerization of silylenoid (Tsi)Cl(2)SiLi (Tsi = C(SiMe(3))(3)) were studied by density functional theory (DFT) at the B3LYP/6-31G(d) level. Four equilibrium structures and three isomeric transition states were located. The three-membered ring and p-complex structures, 1 and 2, are the two most stable forms. Two other local minima, the sigma-complex 3 and tetrahedron structure 4, should rearrange to 1 with very low barriers, and then to the most stable isomer 2. To exploit further the stability of silylenoid (Tsi)Cl(2)SiLi, the insertion reactions of 2 and silylene (Tsi)ClSi into the HF molecule have been investigated at the B3LYP/6-31G(d) level, respectively. The results show that the insertion of 2 into HF is very similar to that of (Tsi)ClSi into HF, but the latter is more favorable. To probe the influence of the substituent Tsi on the stability of silylenoid (Tsi)Cl(2)SiLi, the isomers and insertion reaction of silylenoid CH(3)Cl(2)SiLi were investigated in a similar way of those with (Tsi)Cl(2)SiLi. The results indicate that silylenoid containing very bulky group Tsi exhibits unusual stability because of the severe steric hindrance produced by Tsi at the center to which it is attached.  相似文献   

2.
Two anti-2,4-bis(3-R-phenyl)pentane-2,4-diols (1, R = Me; 2, R = SMe) have been synthesized and were characterized by X-ray diffraction, IR and UV spectra. X-ray diffractions indicate that intra- and intermolecular hydrogen bonding interactions form one-dimensional (1D) ribbons. The adjacent infinite 1D ribbons result in 3D supramolecular structures. The dihedral angles between every two benzene rings in the two diols are 31.61(12) and 31.80(7)°, respectively. UV absorption spectra of the title compounds were recorded in MeOH, C2H5OH, CH3CN, n-BuOH and cyclohexane solvents with different dielectric constants.  相似文献   

3.
Phosphanediyl Transfer from Inversely Polarized Phosphaalkenes R1P=C(NMe2)2 (R1 = tBu, Cy, Ph, H) onto Phosphenium Complexes [(η5‐C5H5)(CO)2M=P(R2)R3] (R2 = R3 = Ph; R2 = tBu, R3 = H; R2 = Ph, R3 = N(SiMe3)2) Reaction of the freshly prepared phosphenium tungsten complex [(η5‐C5H5)(CO)2W=PPh2] ( 3 ) with the inversely polarized phosphaalkenes RP=C(NMe2)2 ( 1 ) ( a : R = tBu; b : Cy; c : Ph) led to the η2‐diphosphanyl complexes ( 9a‐c ) which were isolated by column chromatography as yellow crystals in 24‐30 % yield. Similarly, phosphenium complexes [(η5‐C5H5)(CO)2M=P(H)tBu] (M = W ( 6 ); Mo ( 8 )) were converted into (M = W ( 11 ); Mo ( 12 )) by the formal abstraction of the phosphanediyl [PtBu] from 1a . Treatment of [(η5‐C5H5)(CO)2W=P(Ph)N(SiMe3)2] ( 4 ) with HP=C(NMe2)2 ( 1d ) gave rise to the formation of yellow crystalline ( 10 ). The products were characterized by elemental analyses and spectra (IR, 1H, 13C‐, 31P‐NMR, MS). The molecular structure of compound 10 was elucidated by an X‐ray diffraction analysis.  相似文献   

4.
The Raman spectra of compounds R2NPX2 (R=Me and Et; X=F, Cl, and Br) were studied. The time correlation functions of vibrational and rotational relaxations as well as the characteristic times of these processes were calculated. Conclusions concerning the mechanisms of formation of the contours of the Raman lines with frequencies in the 670–705 cm−1 range corresponding to the totally symmetric vibrations of the P-N bond in the R2NPX2 molecules were drawan. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 961–967, May 1997.  相似文献   

5.
Two new members of the hexanuclear series [Co6S8(PR3)6] n+, complexes [Co6S8(PMe2Ph)6](ClO4) (1) and [Co6S8P(OMe)3 6] (2), have been synthesizes and characterized by X-ray diffraction analyses. Their formation process was postulated to go through trinuclear 3--S bridged moieties. The structural characteristics of the M6E8P6 skeleton of a whole series of [M6E8(PR3)6] n+ (M=Co, Cr, Fe, Mo; E=S, Se, Te) complexes are presented in terms of atomic distances and core volumes.  相似文献   

6.
New air-stable fullerides, (Ph4P)2C60Hal (Hal=Br or I) and (Ph4As)2C60Cl, were synthesized, and their crystal structure were determined. A comparative crystal-chemical analysis of the fullerides under study demonstrated that they are isostructural, described by the general formula (Ph4X)2C60Hal (X=P or As, and Hal=Cl, Br, or I), and crystallize in the triclinic system. The C60 and Hal anions occupy special centrosymmetric positions. The (Ph4P)+ and (Ph4As)+ cations occupy general positions. The principal parameters of the molecular structures are reported. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1982–1986, November, 1997.  相似文献   

7.
A series of titanium(IV) complexes Ti(O‐i‐Pr)Cl3(THF)(PhCOR) (R = H ( 1 ), CH3 ( 2 ), or Ph ( 3 )) is prepared quantitatively from reactions of [Ti(O‐i‐Pr)Cl2(THF)(μ‐Cl)]2 with 2 molar equiv. PhCOR. Treatment of Ti(O‐i‐Pr)Cl3 with 2 molar equiv. of PhCOR affords the disubstituted complexes Ti(O‐i‐Pr)Cl3(PhCOR)2 (R = CH3 ( 4 ) or Ph ( 5 )). The 13C NMR study of these complexes shows that the relative bonding abilities are in the order of PhCOCH3 > PhCHO > PhCOPh. The molecular structure of 5 reveals that one of the benzophenone ligands is trans to the strongest 2‐propoxide ligand with a long Ti‐O(carbonyl) distance of 2.193(5) Å which is much longer than the other Ti‐O(carbonyl) distance of 2.097(4) Å by ?0.1 Å. All ligands cis to the alkoxide ligand are bending away from the alkoxide ligand with the RO‐Ti‐L angles ranging from 93.6(2) to 99.0(2)°.  相似文献   

8.
Reactions of Cyclostibanes, (RSb)n [R = (Me3Si)2CH, n = 3; Me3CCH2, n = 4, 5] with the Transition Metal Carbonyl Complexes [W(CO)5(thf)], [CpxMn(CO)2(thf)], [CpxCr(CO)3]2, and [Co2(CO)8]; Cpx = MeC5H4 (RSb)3 [R = (Me3Si)2CH] reacts with [W(CO)5(thf)], [CpxMn(CO)2(thf)], or [Co2(CO)8] to give [(RSb)3W(CO)5] ( 1 ), [RSb{Mn(CO)2Cpx}2] ( 2 ) or [RSbCo(CO)3]2 ( 3 ). The reaction of (R′Sb)n (n = 4, 5; R′ = Me3CCH2) with [CpxCr(CO)3]2 leads to [(R′Sb)4{Cr(CO)2Cpx}2] ( 4 ); Cpx = MeC5H4, thf = Tetrahydrofuran.  相似文献   

9.
New Arsinidene-bridged Multinuclear Cluster Complexes of Ag and Au. The Crystal Structures of [Ag14(AsPh)6Cl2(PR3)8], (PR3 = PEt3, PMenPr2, PnPr3), [M4(As4Ph4)2(PR3)4], (M = Ag, PR3 = PEt3, PnPr3; M = Au, PR3 = PnPr3), [Au10(AsPh)4(PhAsSiMe3)2(PnPr3)6] The reaction of AgCl with PhAs(SiMe3)2 in presence of tertiary phosphines (PR3) leads to arsinidene-bridged silver clusters with the composition [Ag14(AsPh)6Cl2(PR3)8], (PR3 = PEt3 1 , PMenPr2 2 , PnPr3 3 ). Further it is possible to obtain the multinuclear complexes [Ag4(As4Ph4)2(PR3)4], (PR3 = PEt3 4 , PMenPr2 5 ). In analogy to that [PMe3AuCl] reacts with PhAs(SiMe3)2 and PnPr3 to form the compound [Au4(As4Ph4)2(PnPr3)4] 6 , which is isostructurell to 4 and 5 . The gold cluster [Au10(AsPh)4(PhAsSiMe3)2(PnPr3)6] 7 was obtained from the same solution. The structures were characterized by X-ray single crystal structure analysis. (Crystallographic data see “Inhaltsübersicht”)  相似文献   

10.
Mixed-ligand Complexes of Rhenium. IX. Reactions on the Nitrido Ligand of [ReN(Me2PhP)(Et2dtc)2]. Synthesis, Characterization, and Structures of [Re(NBCl3)(Me2PhP)(Et2dtc)2], [Re(NGaCl3)(Me2PhP)(Et2dtc)2], and [Re(NS)Cl(Me2PhP)2(Et2dtc)] BCl3, GaCl3 and S2Cl2 react with the well-known [ReN(Me2PhP)(Et2dtc)2] by attack of the nucleophilic nitrido ligand. Final products of these reactions are [Re(NBCl3)-(Me2PhP)(Et2dtc)2], [Re(NGaCl3)(Me2PhP)(Et2dtc)2], and [Re(NS)Cl(Me2PhP)2Et2dtc)] which have been studied by mass spectrometry, IR spectroscopy and X-ray diffraction. [Re(NBCl3)(Me2PhP)(Et2dtc)2] crystallizes in the triclinic space group P1 , Z = 2, a = 8.151(6), b = 9.935(8), c = 18.67(1) Å; α = 94.42(4), β = 97.09(1), γ = 101.35(4)°. The coordination geometry is a distorted octahedron. The equatorial coordination sphere is occupied by one phosphorus and three sulphur atoms. The fourth sulphur atom is in trans position to the Re?N? B moiety. The almost linear Re?N? B unit has an Re?N? B angle of 170.5(3)° with a Re? N bond length of 1.704(3) Å. The analogous [Re(NGaCl3)(Me2PhP)(Et2dtc)2] crystallizes in P21/c with a = 8.138(3), b = 18.279(2), c = 19.880(6) Å; β = 99.81(2)°; Z = 4. Rhenium has a distorted octahedral environment. The Re? N? Ga bond is slightly bent with an angle of 154.5(4)° and a Re? N bond length of 1.695(6) Å. [Re(NS)Cl(Me2PhP)2(Et2dtc)] crystallizes in the triclinic space group P1 , Z = 4, a = 9.514(2); b = 16.266(5); c = 18.388(3) Å; α = 88.75(2), β = 76.59(2), γ = 85.50(2)° with two crystallographically independent molecules in the asymmetric unit. Rhenium has a distorted octahedral environment with the chloro ligand in trans position to the almost linear thionitrosyl group. The Re?N bond lengths are 1.795(6) and 1.72(1) Å, respectively, and the N?S distances are 1.55(1) and 1.59(1) Å, respectively.  相似文献   

11.
Molecules of Li(n)X (n = 2, 3; X = Cl, Br, I) were examined with a magnetic sector mass spectrometer by surface ionization using a triple rhenium filament impregnated with fullerene (C60). The ionization energies obtained for Li(2)Cl, Li(2)Br and Li(2)I molecules are 3.8 +/- 0.1, 3.9 +/- 0.1 and 4.0 +/- 0.1 eV, respectively. The first ionization energy of Li(2)Cl is documented, while there are no literature data for the ionization energies of Li(2)Br and Li(2)I. The molecules of Li(3)Cl, Li(3)Br and Li(3)I were detected experimentally for the first time with ionization energies of 4.0 +/- 0.1, 4.1 +/- 0.1 and 4.1 +/- 0.1 eV, respectively. The ionization energies of Li(n)X (n = 2, 3; X = Cl, Br, I) are in correlation with the theoretical prediction of their hyperlithiated configurations.  相似文献   

12.
Using the XRD method, the crystalline and molecular structures of two halogenated propionamides, CF2XCF2CONH2, X = H (I) and Cl (II), have been studied. Crystals I and II are monoclinic: space group P21/c, Z = 4; (I) a = 10.967 Å, b = 5.406 Å, c = 10.063 Å, β = 107.86°; (II) a = 11.979 Å, b = 5.608 Å, c = 10.042 Å, β = 99.31°. Structures I and II were solved by the direct method and refined by the full-matrix least-square method to R = 0.112 (I) and 0.139 (II) over all 1299 (I) and 1175 (II) independent measured reflections (a CAD-4 autodiffractometer, λMoK α).  相似文献   

13.
14.
15.
Mixed-ligand diorganotin esters, [R 2Sn(OP(O)(OH)Ph)(OS(O) 2R (1))] n [R = n-Bu, R (1) = Me ( 1), n-Pr ( 2); R = Et, R (1) = Me ( 3)], have been synthesized by reacting the tin precursors, R 2Sn(OR (1))OS(O) 2R with an equimolar amount of phenylphosphonic acid under mild conditions (room temperature, 6-8 h, CH 2Cl 2). These have been characterized by IR, multinuclear ( (1)H, (13)C{ (1)H}, (31)P, and (119)Sn) NMR, and single crystal X-ray diffraction studies. The asymmetric unit of 1 is comprised of a tetramer with four crystallographically unique tin atoms. The structure reveals a central eight-membered (Sn-O-S-O) 2 cyclic ring with two exocyclic tin atoms, which results from micro 3-binding of the two methanesulfonate groups. The remaining two sulfonates are monodentate and contribute in O...HO(P) hydrogen bonding. The molecular structure is extended into a 3D coordination polymer with the aid of hydrogenphenylphosphonate group on each tin atom, acting in a micro 2-O 2P mode and forms a series of eight-membered (Sn-O-P-O) 2 rings in the structural framework. 2 and 3 are isostructural and represent linear 1D coordination polymers via micro 2-binding mode of both alkanesulfonate and hydrogenphenylphosphonate groups.  相似文献   

16.
The synthesis of trimethylene-bridged carboxylate-substituted tetraorganodistannoxanes {[Me3SiCH2(RCOO)Sn(CH2)3Sn(OOCR)CH2SiMe3]O} n (1, R = Ph; 2, R = 2,4-Me2C6H3) is reported. Depending on the structure of R, in the solid state these compounds are either dimers (1, n = 2, cis-isomer) with a ladder-type structure or tetramers (2, n = 4) with a double ladder-type structure.  相似文献   

17.
Trigonal-Bipyramidal Clusters with Interstitial C2-Units in the Chlorides K[M5(C2)]Cl10 (M = La, Ce, Pr) and Rb[M5(C2)]Cl10 (M = Pr, Nd) The chlorides K[M5(C2)]Cl10 (M = La, Ce, Pr) and Rb[M5(C2)]Cl10 (M = Pr, Nd) are obtained via metallothermic reduction of the trichlorides MCl3 with potassium and rubidium, respectively, in the presence of metal M and carbon in sealed niobium containers at temperatures between 700 and 900°C. They contain trigonal bipyramids, interstitially stabilized by a C2 unit, [M5(C2)], and crystallize with the hexagonal (K[Pr5(C2)]Cl10, Rb[M5(C2)]Cl10 with M = Pr, Nd) or monoclinic (K[M5(C2)]Cl10 with M = La, Ce) crystal system. The trigonal bipyramids are surrounded by nine inner Cl? ligands (capping the nine edges) and by 12 (hexagonal) or 13 (monoclinic) outer ligands and are connected via all of the 21 and 22 ligands, respectively. Special features are Cla-a-a (hexagonal) and Cla-a-a-a (monoclinic) bridges.  相似文献   

18.
采用从头计算MP2方法和密度泛函理论方法,对过渡金属团簇[PdAu8(PR3)8]2+(R=Me,OMe,H,F,Cl,CN)的几何结构、电子结构以及团簇各组成部分之间的结合能进行了研究.MP2方法和SVWN局域泛函能够对团簇的结构给予准确的描述,而离域泛函BP86,PBE,BLYP和杂化泛函B3LYP则过高地估计了团簇的几何结构参数.电子结构研究表明Pd,Au原子通过d电子的成键作用构成团簇内核[PdAu8]2+,[PdAu8]2+与PR3配体则通过"σ给予/π反馈"模式成键.PR3配体与[PdAu8]2+的结合能够加强Pd-Au之间的成键作用,增大前线轨道能级间隙,从而提高团簇的稳定性.PR3配体中 R 基团供、吸电能力的变化对[PdAu8(PR3)8]2+结构的影响较小,但对[PdAu8]2+ -pR3结合能的影响较大.能量分析显示不同PR3与[PdAu8]2+之间具有相近的轨道作用能,与R基团供、吸电能力相关的非轨道作用能成为影响两者连接牢同程度的决定因素.  相似文献   

19.
The salt elimination reaction of the transition carbonyl metal-lates [L(CO)nM](Na/K) (M = Cr, Mo, W, Mn, Re, Fe, Co, Ni; L= CO, n5-C5R5, PR3; n= 1-4; R= alkyl, aryl) with the base-stabilized galliumhalides ClaGaR3 -a(Do) (R = H, alkyl, halide; Do = THF, N(CH3)3, NC7H13) or ClaGa[(CH2)3N-R2](R)2 - a yielded almost quantitatively the transition metal-substituted, gallanes [L(CO)nM]aGaR3 - a(Do) and [L(CO)n-M]aGa[(CH2)3NR2](R)2 - a, respectively. Residual halide functionalities in these complexes were selectively replaced by various other groups. The new compounds were characterized by means of elemental analysis, 1H-, 13C-, 31P-NMR, MS, and lR v(CO) data. The single-crystal X-ray structure analysis of trans-(Ph3P)(CO)3Co-Ga[(CH2) 3N(C2H5)2](R)( 6s : R = Cl, 6t : R= CH3) showed s̀(Co-Ga) lengths of 237.78(4) and 249.5(1) pm, respectively. A short s̀(Fe-Ga) contact of 236.18(3) pm was found for (n5-C5H5)(CO)2Fe-Ga-Cl2[N(CH 3)3] ( 5a ). Low-pressure MOCVD experiments were performed to give thin films of analytically pure CoGa alloy.  相似文献   

20.
The complexes [W(CO)5(Ph2SbX)], X = Cl (1), Br (2) and I (3) were prepared by reaction of [W(CO)5(tetrahydrofuran)] with Ph2SbX. The structures of 1-3 were studied by X-ray diffraction. In the crystals there are weak contacts between the oxygen atoms of the CO ligands and antimony atoms of neighbouring molecules. DFT calculations were carried out for 1 using gradient corrected functional B3LYP. The bonding between Ph2SbCl and the W(CO)5 fragment in 1 was analysed using charge decomposition analysis.  相似文献   

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