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1.
Norbornene reacts with trichlorosilane to generate norbornyltrichlorosilane in high yield. The slow hydrolysis of norbornyltrichlorosilane in acetone yields incompletely condensed norbornyl-silasesquioxanes. The compound C42H70O11Si6 can be isolated from this reaction. On the basis of elemental analyses, 1H, 13C and 29Si NMR, mass spectroscopy, infrared spectroscopy, and crystallographic analysis, C42H70O11Si6 is formulated as [(C7H11)6Si6O7(OH)4], with the Si6O7 framework being composed of two perpendicular Si4O4 planes sharing an edge. [(C7H11)6Si6O7(OH)4] is a putative model of vicinal [Si(OH)]2 sites on the surface of partially dehydroxylated silica. 相似文献
2.
2,4,6-Tri-tert.butylphenyl Substituted Silanes 2,4,6-Tri-tert.butylphenyl lithium reacts with trimethoxysilane, triethoxysilane, and triphenoxysilane to give the dialkoxy- or diphenoxy-(2,4,6-tri-tert.butylphenyl)-silanes Ar? SiH(OR1)2 3 ? 5 (Ar = 2,4,6-tri.tert.butylphenyl, R1 = Me, Et, Ph). Interaction of methyl lithium or n-butyl lithium with 3 – 5 leads under partial or complete substitution of the OR1-functions to the silanes Ar? SiH(OR1)R2 7 – 11 and Ar? SiHR22 12 and 13 (R2 = Me, Bu). Reaction of 3 with lithium tert.butul-amide gives tert.butylamino-methoxy-(2,4,6-tri-tert.butylphenyl)-silane 14 . 5 is reduced by LiAlH4 to 2,4,6-tri-tert.butylphenyl-silane 6 . The reaction of 3 with antimony trifluoride results in formation of 2,4,6-tri-tert.butylphenyl trifluorosilane 2 . Attempts to replace the alkoxy or phenoxy groups in 3 – 5 by chlorine led under silion carbon bond cleavage to 1,3,5-tri-tert.butylbenzene. 相似文献
3.
Phosphoraneiminato Complexes of Vanadium. The Crystal Structure of [V3Cl6(NPMe3)5+]2[V4O4Cl8(NPMe3)22?] · 6 CH3CN Vanadiumtetrachloride reacts in CCl4 solution with Me3SiNPMe3 to form the donor acceptor complex [VCl4(Me3SiNPMe3)], which reacts with excess Me3SiNPMe3 in boiling acetonitrile to form the phosphoraneiminato complex [V3Cl6(NPMe3)5]+Cl?. Partial hydrolysis in acetonitrile solution leads to black single crystals of [V3Cl6(NPMe3)5+]2[V4O4Cl8(NPMe3)22?] · 6 CH3CN, which are characterized by a crystal structure determination. Space group P21/c, Z = 2, structure solution with 3 008 observed unique reflections, R = 0.090. Lattice dimensions at ?70°C: a = 1 379.0, b = 1 915.8, c = 2 278 pm, β = 102,79°. In the complex cation the three vanadium atoms form a trigonal bipyramid with two μ3-NPMe3 groups; the residual NPMe3? groups and the chlorine atoms are in terminal functions. In the anion [V4O4Cl8(NPMe3)2]2? the vanadium atoms are linked by μ2-O atoms to form a rectangle; in addition the two phosphoraneiminato ligands form μ2-N bridges. 相似文献
4.
Lanthanoid Peroxo Complexes with μ3‐η2:η2:η2‐(O22—) Coordination. Crystal Structures of [Ln4(O2)2Cl8(Py)10] · Py mit Ln = Sm, Eu, Gd The four‐nuclear peroxo complexes [Ln4(O2)2Cl8(Py)10]·py (py = pyridine) with Ln = Sm ( 1 ·py), Eu ( 2 ·py) und Gd ( 3 ·py) are formed as pale yellow ( 1 ·py) and colourless ( 2 ·py and 3 ·py) crystals by action of atmospheric oxygen on heated solutions of the anhydrous trichlorides LnCl3 in pyridine/ diacetone alcohol (4‐hydroxy‐4‐methyl‐2‐pentanone). According to the X‐ray structural analyses the three complexes crystallize isostructural in the triclinic space group PP1¯ with two formula units per unit cell. 1—3 form centrosymmetrical molecular structures, in which the four lanthanoid atoms in coplanar array are linked via the two peroxo groups in a hitherto unobserved μ3‐η2:η2:η2 coordination. Additionally, they are bonded by four �μchloro bridges. Two of the Ln atoms complete their coordination sphere by three pyridine molecules each, the other two by two chlorine atoms and two pyridine molecules. The gadolinium compound is additionally characterized by its complete vibrational spectrum (i.r. and Raman). 相似文献
5.
Substitution Products of 4,4,6,6-Tetrachloro-6′-phenoxy-6′ -thioxo-cyclotriphosphazene-2-spiro-3′-cyclodi(phosphadiazane) Reactions of the spiro compound 4,4,6,6-Tetrachloro-6′-phenoxy-6′-thioxo-cyclotriphosphazene-2-spiro-3′-cyclodi(phosphadiazene) Cl4N3P3(NH? NH)2P(S)OC6 H5 with an excess of ammonia, cyclopropylamine, aziridine, and sodium phenolate were investigated. Fully or partially substitution of the chlorine atoms occurs. The reaction with two equivalents of the aziridine yields a mixture of isomers which consists of two geminal and two vicinal disubstituted products. The constitutions of the substituted compounds were confirmed by IR, NMR, MS and elemental analyses. 相似文献
6.
E. Ya. Misochko A. V. Akimov A. A. Mazitov D. V. Korchagin S. V. Chapyshev 《Russian Chemical Bulletin》2012,61(12):2218-2224
An ESR spectrum of high-symmetry septet 1,3,5-trinitreno-2,4,6-trichlorobenzene generated under photolysis of 1,3,5-triazido-2,4,6-trichlorobenzene in solid argon at 15 K was recorded. Computer simulation revealed that the spectrum corresponds to the septet spin state with the fine structure parameters D S = ?0.0957±0.0006 cm?1 and E S = 0±0.0004 cm?1. These values of the magnetic anisotropy parameters D S and E S are in good agreement with the results of UDFT calculations. The spin-spin (D SS) and spin-orbit (D SO) coupling parameters of septet molecules with D 3h symmetry are negative and mutually enhance the magnetic anisotropy of these molecules. The contribution of the spin-orbit coupling to the magnetic anisotropy of 1,3,5-trinitreno-2,4,6-trichlorobenzene is higher than 11% due to the presence of three chlorine atoms in the molecule. This suggests the possibility of further strengthening the magnetic properties of septet 1,3,5-trinitrenobenzenes by introducing bromine and iodine atoms into positions 2, 4, and 6 of their benzene rings. 相似文献
7.
Two [MoOCl3(THF)2] molecules are used for detachment of two Cl atoms from [MgCl2(THF)2]. In such reaction a green crystalline salt [Mg(THF)6][MoOCl4THF]2 IV is formed. Compound IV reacts further with 3 equivalents of bis(tetrahydrofuran)magnesium dichloride, yielding a green ionic [Mg2(m?-Cl)3(THF)6][MoOCl4THF] compound V . Compound IV and V vary only in a structure of cation what indicated that the tri-m?-chlorohexakis(tetrahydrofuran)dimagnesium(II) cation in V is really formed in reaction between [Mg(THF)6]2+ cation and [MgCl2(THF)2]. The crystal structure of compounds IV and V has been solved by X-ray diffraction method. The [Mg(THF)6]2+ cation forms the tetragonally distorted octahedron with the magnesium atom in the symmetry centre. In homobimetallic di-octahedral [Mg2(m?-Cl)3(THF)6]+ cation the magnesium atoms are surrounded by three bridging chlorine atoms and three THF molecules. The structures of [MoOCl4THF]? in IV and V are similar. In those anions the molybdenum atom is hexacoordinated with four chlorine atoms in equatorial plane. 相似文献
8.
In order to unambiguously assign the 29Si-NMR chemical shifts of polydisilahydrocarbons containing structural units -CH2Si1(R1R2)Si2(R1R2)CHPh-, where R1=R2=Me or Ph, a model polymer viz., poly(tetramethyldisilyleneethylene) was synthesised through the dechlorination of 1,2-bis(chlorodimethylsilyl)ethane using potassium in toluene. The 29Si-NMR spectrum of this polymer shows only one resonance peak at δ=−15.1 ppm due to Si atoms in the structural units, -CH2Si(Me)2Si(Me)2CH2- which unambiguously reveals that the chemical shift in the up field region of polydisilahydrocarbons containing structural units -CH2Si1(R1R2)Si2(R1R2)CH(Ph)- is due to Si1, i.e., silicon attached to -CH2- and accordingly, the chemical shift in the down field region is due to Si2, i.e., silicon attached to -CH(Ph)-. 相似文献
9.
Preparation and Crystal Structure of a Potassium Imidenitridesilicate, K3Si6N5(NH)6 Crystals of K3Si6N5(NH)6 sufficient for an X-ray structure determination are formed when potassium and silicium react with supercritical ammonia under the following conditions K:Si = 1:1, P(NH)3 = 6 kbar, T = 500°C within 3 days in a temperature gradient within the autoclaves used. The compound crystallizes cubic with a = 10.789(4) Å, the space group is P4332 (with tests for enantiomorphous pairs) and the cell contains four formula units. The positions of H-atoms are determined. The following data characterize the structure determination: N(F) = 518 with 517 ≥ 3σ(F02) N(Variables) = 37, R = 0.019 resp. Rw = 0.017. The conditions for the synthesis of the compound and its structure are discussed with respect to Si3N4 and Si2N2(NH). 相似文献
10.
《Angewandte Chemie (International ed. in English)》2017,56(44):13866-13871
The reduction of the tribromoamidosilane {N(SiMe3)Dipp}SiBr3 (Dipp=2,6‐i Pr2C6H3) with potassium graphite or magnesium resulted in the formation of [Si4{N(SiMe3)Dipp}4] ( 1 ), a bicyclo[1.1.0]tetrasilatetraamide. The Si4 motif in 1 does not adopt a tetrahedral substructure and exhibits two three‐coordinate and two four‐coordinate silicon atoms. The electronic situation on the three‐coordinate silicon atoms is rationalized with positive and negative polarization based on EPR analysis, magnetization measurements, and DFT calculations as well as 29Si CP MAS NMR and multinuclear NMR spectroscopy in solution. Reactivity studies with 1 and radical scavengers confirmed the partial charge separation. Compound 1 reacts with sulfur to give a novel type of silicon sulfur cage compound substituted with an amido ligand, [Si4S3{N(SiMe3)Dipp}4] ( 2 ). 相似文献
11.
Dorothea Wolff von Gudenberg Gerlinde Frenzen Werner Massa Kurt Dehnicke 《无机化学与普通化学杂志》1995,621(4):525-530
The Crystal Structures of (NH4)2[ReCl6], [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN and [ReCl4(18)(Crown-6)] Brown single crystals of (NH4)2[ReCl6] are formed by the reaction of NH4Cl with ReCl5 in a suspension of diethylether. [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN crystallizes as brown crystal plates from a solution of ReCl5 in acetonitrile. Lustrous green single crystals of [ReCl4(18-crown-6)] are obtained by the reaction of 18-crown-6 with ReCl5 in a dichloromethane suspension. All rhenium compounds are characterized by IR spectroscopy and by crystal structure determinations. (NH4)2[ReCl6]: Space group Fm3 m, Z = 4, 75 observed unique reflections, R = 0.01. Lattice constant at ?70°C: a = 989.0(1) pm. The compound crystallizes in the (NH4)2[PtCl6] type, the Re? Cl distance is 235.5(1) pm. [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN: Space group P1, Z = 1, 2459 observed unique reflections, R = 0.12. Lattice dimensions at ?60°C: a = 859.0(1), b = 974.2(7), c = 1287.3(7) pm, α = 102.69(5)°, b? = 105.24(7)°, γ = 102.25(8)°. The structure consists of two symmetry-independent [ReCl2(CH3CN)4]+ ions with trans chlorine atoms, [ReCl6]2? ions, and included acetonitrile molecules. In the cations the Re? Cl bond lengths are 233 pm in average, in the anion they are 235 pm in average. [ReCl4(18-crown-6)]: Space group P21/n, Z = 4, 3 633 observed unique reflections, R = 0.06. Lattice dimensions at ?70°C: a = 1040.2(4), b = 1794.7(5), c = 1090.0(5) pm, b? = 108.91(4)°. The compound forms a molecular structure, in which the rhenium atom is octahedrally coordinated by the four chlorine atoms and by two oxygen atoms of the crown ether molecule. 相似文献
12.
Jan Keuter Alexander Hepp Christian Mück‐Lichtenfeld Felicitas Lips 《Angewandte Chemie (International ed. in English)》2019,58(13):4395-4399
Reaction of the bicyclo[1.1.0]tetrasilatetraamide Si4{N(SiMe3)Dipp}4 1 (Dipp=2,6‐diisopropylphenyl) with 5 equiv of the N‐heterocyclic carbene NHCMe4 (1,3,4,5‐tetramethylimidazol‐2‐ylidene) affords a bifunctional carbene‐coordinated four‐membered‐ring compound with a Si=N group and a two‐coordinate silicon atom Si4{N(SiMe3)Dipp}2(NHCMe4)2(NDipp) 2 . When 2 reacts with 0.25 equiv sulfur (S8), two sulfur atoms add to the divalent silicon atom in plane and perpendicular to the plane of the Si4 ring, which confirms the silylone character of the two‐coordinate silicon atom in 2 . 相似文献
13.
Sujin Han Jinkwon Kim 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(10):m521-m522
The title compound, [Mn(NCS)2(C18H12N6)2(CH4O)2], contains a centrosymmetric octahedral MnII centre and three pairs of trans‐coordinating ligands. It is the first example of a mononuclear metal complex with the 2,4,6‐tri(4‐pyridyl)‐1,3,5‐triazine (tpt) ligand. Intermolecular π–π stacking of the planar tpt ligands, as well as hydrogen bonds between pyridyl N and methanol H atoms, results in the formation of a three‐dimensional network. 相似文献
14.
《Journal of Coordination Chemistry》2012,65(3-4):267-284
Abstract Infrared spectra of the coordination compounds [MG2(py)2], M(II)=Co, Ni, Cu and Zn; G=glycolato, py=pyridine, have been fully assigned by means of py and py-d 5 and glycolato α—OH and α—OD (G-d) labelling as well as metal ion substitution in the 4000–70cm?1 region. The crystal structure of the Ni(II) compound is presented and the spectra of the compounds are discussed on the basis of their structure and their bonding to the glycolato and pyridine ligands. Vibrational frequencies obtained for the Ni(II) compound are compared to those obtained by calculations carried out using the Gaussian 94 program package. 相似文献
15.
The mixed-valence Cu3Cl4 · 2C3N3(OC3H5)3 π-complex (I) is synthesized from 2,4,6-triallyloxy-1,3,5-triazine (L) and copper(II) chloride by the alternating-current electrochemical method in an ethanolic solution. Single crystals of complex I are studied by X-ray diffraction analysis: space group I41/a, a = 25.39(8), c = 10.14(6) Å, V = 6537(48) Å3, Z = 8, R = 0.0814. The copper(I) and chlorine atoms form unique cyclic tetramers Cu4Cl4. The coordination sphere of each copper(I) atom includes the C=C bond of the allyl group of the ligand molecule L in addition to the two bridging chlorine atoms. Two nearest triazine rings are coordinated through the nitrogen atoms to the copper(II) atoms, whose environment is completed to a square with two chlorine atoms. An intricate three-dimensional structure is formed due to the μ4-bridging function of the cupro(I) tetramer and the μ2-bridging function of the ligand molecule L. 相似文献
16.
Michael G. B. Drew Michael J. Hudson Peter B. Iveson Charles Madic 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):434-435
The title compound, aquatris(nitrato)[2,4,6‐tris(2‐pyridyl)‐1,3,5‐triazine]samarium dihydrate, [Sm(NO3)3(C18H12N6)(H2O)]·2H2O, was prepared from Sm(NO3)3·6H2O and 2,4,6‐tris(2‐pyridyl)‐1,3,5‐triazine. The metal atom is ten‐coordinate being bonded to the terdentate TPTZ ligand, three bidentate nitrates and a water molecule. 相似文献
17.
The nucleophilic substitution of one chlorine atom in 2,4-dichloro-6-dihexylamino-1,3,5-triazine ( 1 ) by amines 2a-c leads to the alkylamino-chlorodihexylamino-1,3,5-triazines 3a-c . Typical signals in the 1H-nmr spectra of structure type 3 are the triplet at 0.9 ppm for the terminal methyl groups and the multiplet at 3.3–3.65 ppm for the methylene groups neighboring the nitrogen atoms. Compound class 3 comprises representatives exhibiting antidiabetic, trichomonacidal, antiviral and anthelminthic activity. 相似文献
18.
L’ubica Triščíková Ivan Potočňák Jozef Chomič Peter Baran 《Transition Metal Chemistry》2006,31(4):504-515
The new mixed-valence mixed-metal complex Cu(py)6Cu2Ag2(CN)6 (py = pyridine) possesses a three dimensional polymeric crystal structure. The Cu(I) atom is tetrahedrally coordinated by
two nitrogen atoms of pyridine molecules, by one nitrogen atom of the dicyanoargentate anion and by one carbon atom of the
cyano group. Both the dicyanoargentate anion and the cyano group bridge the Cu(I) atom with neighboring Cu(II) atoms. These
are hexacoordinated in the form of an elongated tetragonal bipyramid. The equatorial plane is formed by two nitrogen atoms
from two pyridine molecules and two nitrogen atoms from bridging cyano groups. Axial positions are occupied by nitrogen atoms
of the bridging [Ag(CN2]− anions. Correlation between structures of the title compound and seven other dicyanoargentates with their i.r. spectra has
been studied. The coordination mode of [Ag(CN2]− anions in compounds Cu8-xAgx(tn)3(CN)10 x = 0.25, Cu(3-Mepy)2Ag2(CN)4, Cu(py)2Ag2(CN)4 and Cu(py)4Ag2(CN)4 (tn is 1,3-diaminopropane, 3-Mepy is 3-methylpyridine) is predicted based on this correlation. 相似文献
19.
On the Critical Effect of the Metal (Mo vs. W) on the [3+2] Cycloaddition Reaction of M3S4 Clusters with Alkynes: Insights from Experiment and Theory
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Dr. Emilio Bustelo Dr. Artem L. Gushchin Dr. M. Jesús Fernández‐Trujillo Prof. Dr. Manuel G. Basallote Dr. Andrés G. Algarra 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(42):14823-14833
Whereas the cluster [Mo3S4(acac)3(py)3]+ ([ 1 ]+, acac=acetylacetonate, py=pyridine) reacts with a variety of alkynes, the cluster [W3S4(acac)3(py)3]+ ([ 2 ]+) remains unaffected under the same conditions. The reactions of cluster [ 1 ]+ show polyphasic kinetics, and in all cases clusters bearing a bridging dithiolene moiety are formed in the first step through the concerted [3+2] cycloaddition between the C?C atoms of the alkyne and a Mo(μ‐S)2 moiety of the cluster. A computational study has been conducted to analyze the effect of the metal on these concerted [3+2] cycloaddition reactions. The calculations suggest that the reactions of cluster [ 2 ]+ with alkynes feature ΔG≠ values only slightly larger than its molybdenum analogue, however, the differences in the reaction free energies between both metal clusters and the same alkyne reach up to approximately 10 kcal mol?1, therefore indicating that the differences in the reactivity are essentially thermodynamic. The activation strain model (ASM) has been used to get more insights into the critical effect of the metal center in these cycloadditions, and the results reveal that the change in reactivity is entirely explained on the basis of the differences in the interaction energies Eint between the cluster and the alkyne. Further decomposition of the Eint values through the localized molecular orbital‐energy decomposition analysis (LMO‐EDA) indicates that substitution of the Mo atoms in cluster [ 1 ]+ by W induces changes in the electronic structure of the cluster that result in weaker intra‐ and inter‐fragment orbital interactions. 相似文献
20.
Sergio Baggio M. Enriqueta Díaz de Vivar Ricardo Baggio María Teresa Garland 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(5):m195-m198
The title compound, [Cd2(SO3)2(C18H12N6)2]·8H2O, is a dimer built up around a symmetry center, where the sulfite anion displays a so far unreported coordination mode in metal‐organic complexes; the anion binds as a μ2‐sulfite‐κ4O,O′:O′,O′′ ligand to two symmetry‐related seven‐coordinate CdII cations, binding through its three O atoms by way of two chelate bites with an O atom in common, which acts as a bridge. The cation coordination is completed by a 2,4,6‐tri‐2‐pyridyl‐1,3,5‐triazine ligand acting in its usual tridentate mode. 相似文献