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1.
Crystal Structure of a Lithiumsilylamidebutanide Colorless single crystals of {Li6[Me2(H)Si—N—Si(H)—(CHMe2)2]2[n‐C4H9]4} ( 1 ) were obtained from a solution of Me2(H)SiN(Li)Si(H)(CHMe2)2 and n‐C4H9Li in n‐hexane. The X‐ray analysis showed that the core of 1 is a distorted octahedron of lithium atoms with ten long and with two short LiÄLi distances. Four of the eight triangular Li3 faces are capped by an n‐butyl group. The nitrogen atoms of the amide groups are situated about opposite edges of adjacent unoccupied Li3 faces. (Si)H····Li interactions exist between the hydridic H atom of each Me2(H)Si group and one Li atom.  相似文献   

2.
Poly(triazine imide) with intercalation of lithium and chloride ions (PTI/Li+Cl?) was synthesized by temperature‐induced condensation of dicyandiamide in a eutectic mixture of lithium chloride and potassium chloride as solvent. By using this ionothermal approach the well‐known problem of insufficient crystallinity of carbon nitride (CN) condensation products could be overcome. The structural characterization of PTI/Li+Cl? resulted from a complementary approach using spectroscopic methods as well as different diffraction techniques. Due to the high crystallinity of PTI/Li+Cl? a structure solution from both powder X‐ray and electron diffraction patterns using direct methods was possible; this yielded a triazine‐based structure model, in contrast to the proposed fully condensed heptazine‐based structure that has been reported recently. Further information from solid‐state NMR and FTIR spectroscopy as well as high‐resolution TEM investigations was used for Rietveld refinement with a goodness‐of‐fit (χ2) of 5.035 and wRp=0.05937. PTI/Li+Cl? (P63cm (no. 185); a=846.82(10), c=675.02(9) pm) is a 2D network composed of essentially planar layers made up from imide‐bridged triazine units. Voids in these layers are stacked upon each other forming channels running parallel to [001], filled with Li+ and Cl? ions. The presence of salt ions in the nanocrystallites as well as the existence of sp2‐hybridized carbon and nitrogen atoms typical of graphitic structures was confirmed by electron energy‐loss spectroscopy (EELS) measurements. Solid‐state NMR spectroscopy investigations using 15N‐labeled PTI/Li+Cl? proved the absence of heptazine building blocks and NH2 groups and corroborated the highly condensed, triazine‐based structure model.  相似文献   

3.
The Crystal Structures of {Li3(12-crown-4)2[HC(CN)2]3}, {Na(15-crown-5)[HC(CN)2]}, and {NaN(nBu)4[HC(CN)2]2 · THF} The preparation and the crystal structures of the title compounds 1 — 3 are described. 1 forms a polymeric chain structure, in which one of the lithium ions is linked by Li…NCC(H)CN… bridges. The remaining lithium ions form (12-crown-4)Li[NCC(H)CN] units, which are coordinated by one of the nitrogen atoms of the dicyanomethanide ions with the lithium ions of the chain. 2 forms an ion pair, in which the sodium ion is coordinated by the five oxygen atoms of the crown ether molecule and by one nitrogen atom of the dicyanomethanide ion. 3 has a threedimensional network, in which the sodium ions are coordinated in a distorted tetrahedral manner by the nitrogen atoms of the dicyanomethanide ions. In the cavities of the network the tetrabutylammonium ions and the THF molecules are found.  相似文献   

4.
The title complex, [Li2(C6H3N2O5)2(H2O)4], contains two kinds of Li atoms, viz. five‐coordinated and four‐coordinated. The five‐coordinated Li ion has a tetragonal–pyramidal geometry, with a water molecule in the apical position and four O atoms from two 2,4‐dinitrophenolate (2,4‐DNP) ligands in the basal plane. The four‐coordinated Li ion has a tetrahedral geometry, with three water molecules and one phenolate O atom of a 2,4‐DNP ligand. The Li ions are bridged by a phenolate O atom, giving the complex a dinuclear structure. The crystal packing is stabilized by O—H...O hydrogen‐bonding interactions involving the water molecules and nitro O atoms.  相似文献   

5.
The reaction of 4‐Amino‐6‐methyl‐1, 2, 4‐triazine‐3(2H)‐thione‐5‐one (HAMTTO) with n‐butyl lithium in dimethoxyethane (DME) gives the complex [Li(DME)(AMTTO)] ( 1 ). 1 was characterized by elemental analysis, IR‐ and mass‐spectrometry and an X‐ray structure analysis [space group P21/n, Z = 4, lattice dimensions at —80 °C: a = 867.6(1), b = 1721.5(2), c = 931.8(1) pm, β = 112.81(1)°, R1 = 0.0315. The complex is a coordination polymer along [001] with a zig‐zag arrangement.  相似文献   

6.
In the title compound, catena‐poly[lithium‐μ3‐ethyl­ene­diphos­phon­ato], [Li(C2H7O6P2)]n, the supra­molecular monoclinic (C2/c) structure consists of one‐dimensional lithium chains [Li⋯Li = 2.7036 (8) Å] that are embedded within ethyl­ene­diphosphon­ate anions linked by strong symmetric hydrogen bonds [O⋯O = 2.473 (3) Å]. The Li atoms and the H atom in the symmetric hydrogen bond reside on twofold rotation axes and there is an inversion center at the mid‐point of the C—C bond of the ethylenediphosphonate ligand.  相似文献   

7.
Syntheses and Crystal Structures of the Nitrido‐chloro‐molybdates [Mg(THF)4{NMoCl4(THF)}2] · 4 CH2Cl2 and [Li(12‐Crown‐4)(NMoCl4)]2 · 2 CH2Cl2 Both the title compounds as well as [Li(12‐crown‐4)2]+MoNCl4 were made from MoNCl3 and the chlorides MgCl2 and LiCl, respectively, in dichloromethane suspensions in the presence of tetrahydrofuran and 12‐crown‐4, respectively. They form orange‐red moisture‐sensitive crystals, which were characterized by their IR spectra and partly by crystal structure analyses. [Mg(THF)4{NMoCl4(THF)}2] · 4 CH2Cl2 ( 1 ): space group C2/m, Z = 2, lattice dimensions at –50 °C: a = 1736.6(1), b = 1194.8(1), c = 1293.5(2) pm; β = 90.87(1)°; R1 = 0.037. In 1 the magnesium ion is coordinated octahedrally by the oxygen atoms of the four THF molecules and in trans‐position by the nitrogen atoms of the two [N≡MoCl4(THF)] ions. [Li(12‐crown‐4)(NMoCl4)]2 · 2 CH2Cl2 ( 2 ): space group P 1, Z = 1, lattice dimensions at –70 °C: a = 930.4(1), b = 957.9(1), c = 1264.6(1) pm; α = 68.91(1)°, β = 81.38(1)°, γ = 63.84(1)°; R1 = 0.0643. 2 forms a centrosymmetric ion ensemble in the dimeric cation of which, i. e. [Li(12‐crown‐4)]22+, the lithium ions on the one hand are connected to the four oxygen atoms each of the crown ether molecules in a way not yet known; and in addition, each of the lithium ions enters into a intermolecular Li–O bond with neighboring crown ether molecules under formation of a Li2O2 four‐membered ring. The two N≡MoCl4 counterions are loosely coordinated to one oxygen atom each of the crown ether molecules with Mo–O distances of 320.2 pm.  相似文献   

8.
The title compound {systematic name: catena‐poly[lithium(I)‐μ3‐acetylsalicylato‐hemi‐μ2‐aqua]}, {[Li(C9H7O4)]·0.5H2O}n, is the hemihydrate of the lithium salt of aspirin. The carboxylate groups and water molecules bridge between Li atoms to form a one‐dimensional coordination chain composed of two distinct ring types. The water O atom lies on a twofold axis. Hydrogen bonding between water donors and carbonyl acceptors further links the coordination chains to form a sheet structure.  相似文献   

9.
An Unusual Biphenylsubstituted Lithiumchlorotriarylsamarate The reaction of the lithium biphenyl LiPmph (Pmph = 2′,3′,4′,5′,6′‐pentamethylbiphenyl) with samarium trichloride in a molar ratio of 3 to 1 affords under elimination of only 2 equivalents lithium chloride the lithium samarate [(thf)3Li][ClSm(Pmph)3(thf)] in a yield of 45°. In the obtained contact ion pair the samarium atom shows an only slightly distorted trigonal bipyramid coordination. Equatorial and axial positions are occupied by three propeller like arranged biphenyl substituents, the Cl{···Li(thf)3} ligand, and a THF molecule, respectively. A rather unusual folding of the aryl ligands leads to comparably short distances of the Sm atom to the ortho‐C–H‐bonds and therefore to the formation of strong agostic interactions.  相似文献   

10.
A series of 3‐substituted 1,2,3‐benzotriazin‐4‐ones, 1 and 2, were synthesized by standard methods and the 15N NMR spectra were recorded. All spectra were obtained using the natural abundance of the nitrogen‐15 isotope. The chemical shifts appear in the normal range for N‐1, N‐2 and N‐3 of the triazine ring, and also correlate with the chemical shifts in the spectra of the imidazolotriazinone, 4, and the imidazolotetrazinone, 5. Significantly, the spectra of 1a, 2 and 4, recorded with full NOE, show inversion of the singlet assigned to N‐3, demonstrating that these compounds exist in the tautomeric form shown. The structure of the 4‐iminobenzotriazinone (3) was confirmed by this 15N NMR analysis. The spectrum shows a signal for the NH‐bearing imino‐nitrogen atom, which is an inverted singlet in the NOE spectrum, whereas the signal from the N‐3 atom of 3 is not inverted in the NOE spectrum. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

11.
The reactivity of cyanuric acid towards alkali triazinetricarboxylates was investigated and the first triazine‐triazine adduct phases comprising alkali metal ions were synthesized and characterized by single‐crystal X‐ray diffraction and thermal analysis. An investigation of the reaction between the alkali triazine tricarboxylates M3[C3N3(CO2)3] · xH2O (M = Li, Na, K, Rb, Cs) and cyanuric acid showed that the degree of ion transfer from triazine tricarboxylate to cyanuric acid increases gradually from the lithium to the cesium salt reflecting an increasing basicity of the triazine tricarboxylates.The reaction of potassium and rubidium triazine tricarboxylate dihydrate with cyanuric yielded the novel co‐crystalsK3[C3N3(CO2)3][C3N3O3H3] · H2O ( 3a ) and Rb3[C3N3(CO2)3][C3N3O3H3] · H2O ( 3b ). In comparison to metal free triazine‐triazine adduct phases in these compounds the assembly of molecules in the crystal is mainly determined by Coulomb interactions and only to a certain degree by hydrogen bonds and dispersive interactions. In the crystal the s‐triazine units exhibit a layered structure with triazine tricarboxylate and isocyanuric acid being arranged in zigzag strands within the layers and stacked in columns perpendicular to the layers. Thermal analysis revealed a quite weak cohesion between triazine tricarboxylate and cyanuric acid upon heating.  相似文献   

12.
A lithium salt of 8-hydroxyquinoline-5-sulfonic acid, Li2(C9H5NO4S)·4H2O, has been synthesized and characterized by X-ray diffraction techniques. The salt is monoclinic, space group P21/c, with a?=?10.323(3), b?=?10.088(9), c?=?11.792(6)?Å and β?=?92.21(3)°. Li ions adopt two different distorted tetrahedral geometries. Li(1) is surrounded by a water molecule, N,O atoms of the oxine ring and one of the oxygen atoms of the sulphonate group. Li(2) is surrounded by three water molecules and an oxygen atom of the sulphonate group. The two lithium ions are bridged by a water molecule, leading to a polymeric network.  相似文献   

13.
Preparation, Characterization and Reaction Behaviour of Sodium and Potassium Hydridosilylamides R2(H)Si—N(M)R′ (M = Na, K) — Crystal Structure of [(Me3C)2(H)Si—N(K)SiMe3]2 · THF The alkali metal hydridosilylamides R2(H)Si—N(M)R′ 1a‐Na — 1d—Na and 1a‐K — 1d‐K ( a : R = Me, R′ = CMe3; b : R = Me, R′ = SiMe3; c : R = Me, R′ = Si(H)Me2; d : R = CMe3, R′= SiMe3) have been prepared by reaction of the corresponding hydridosilylamines 1a — 1d with alkali metal M (M = Na, K) in presence of styrene or with alkali metal hydrides MH (M = Na, K). With NaNH2 in toluene Me2(H)Si—NHCMe3 ( 1a ) reacted not under metalation but under nucleophilic substitution of the H(Si) atom to give Me2(NaNH)Si—NHCMe3 ( 5 ). In the reaction of Me2(H)Si—NHSiMe3 ( 1b ) with NaNH2 intoluene a mixture of Me2(NaNH)Si—NHSiMe3 and Me2(H)Si—N(Na)SiMe3 ( 1b‐Na ) was obtained. The hydridosilylamides have been characterized spectroscopically. The spectroscopic data of these amides and of the corresponding lithium derivatives are discussed. The 29Si‐NMR‐chemical shifts and the 29Si—1H coupling constants of homologous alkali metal hydridosilylamides R2(H)Si—N(M)R′ (M = Li, Na, K) are depending on the alkali metal. With increasing of the ionic character of the M—N bond M = K > Na > Li the 29Si‐NMR‐signals are shifted upfield and the 29Si—1H coupling constants except for compounds (Me3C)(H)Si—N(M)SiMe3 are decreased. The reaction behaviour of the amides 1a‐Na — 1c‐Na and 1a‐K — 1c‐K was investigated toward chlorotrimethylsilane in tetrahydrofuran (THF) and in n‐pentane. In THF the amides produced just like the analogous lithium amides the corresponding N‐silylation products Me2(H)Si—N(SiMe3)R′ ( 2a — 2c ) in high yields. The reaction of the sodium amides with chlorotrimethylsilane in nonpolar solvent n‐pentane produced from 1a‐Na the cyclodisilazane [Me2Si—NCMe3]2 ( 8a ), from 1b‐Na and 1‐Na mixtures of cyclodisilazane [Me2Si—NR′]2 ( 8b , 8c ) and N‐silylation product 2b , 2c . In contrast to 1b‐Na and 1c‐Na and to the analogous lithium amides the reaction of 1b‐K and 1c‐K with chlorotrimethylsilane afforded the N‐silylation products Me2(H)Si—N(SiMe3)R′ ( 2b , 2c ) in high yields. The amide [(Me3C)2(H)Si—N(K)SiMe3]2·THF ( 9 ) crystallizes in the space group C2/c with Z = 4. The central part of the molecule is a planar four‐membered K2N2 ring. One potassium atom is coordinated by two nitrogen atoms and the other one by two nitrogen atoms and one oxygen atom. Furthermore K···H(Si) and K···CH3 contacts exist in 9 . The K—N distances in the K2N2 ring differ marginally.  相似文献   

14.
The title compound, lithium trimanganese bis­[trioxo­selenate(IV)] hexa­kis[hydrogentrioxoselenate(IV)], is built up from a vertex‐sharing network of distorted MnIIIO6 octa­hedra, SeO3 and HSeO3 pyramids and unusual Li(OH)6 octa­hedra, resulting in a dense three‐dimensional structure. Mn, Li and one Se atom have site symmetries of , , and 3, respectively. An O—H⋯O hydrogen bond helps to establish the crystal packing.  相似文献   

15.
Syntheses and Structures of the Lithiumtitanates(III)/(IV) (py)2Li[(py)2Ti(OPh)4] and (py)2Li[(py)Ti(OPh)5] The new lithiumtitanates (py)2Li[(py)2Ti(OPh)4] ( 1 ) and (py)2Li[(py)Ti(OPh)5] ( 2 ) have been obtained from the reaction of titaniumtrichloride (respectively titaniumtetrachloride 2 ) with LiOPh in the presence of the base pyridine (py). The crystal structures of both compounds show that the titanium atoms are in the centres of distorted octahedral coordination figures. In compound 1 , four oxygen and two nitrogen atoms (in cis orientation) are bonded to titanium, whereas in 2 , five oxygen and one nitrogen atom form the coordination polyeder around titanium. In both compounds, the lithium atoms are attached through phenolate bridges to the octahedra. The titanate (py)2Li[(py)2Ti(OPh)4] ( 1 ) has a single absorption band in the visible region of the UV‐spectrum showing a shoulder shifted to the bathochromic region, due to the Jahn‐Teller‐effect for d1‐systems.  相似文献   

16.
Reaction of PdCl2(CH3CN)2 with the sodium salt of 5‐mercapto‐1‐methyltetrazole (MetzSNa) in methanol solution affords an interesting dinuclear palladium complex [Pd2(MetzS)4 ] ( 1 ). However, treatment of PdCl2(CH3CN)2 with neutral MetzSH ligand in methanol solution produces a mononuclear palladium complex [Pd(MetzSH)4]Cl2 ( 2 ). Both complexes were characterized by IR, 1HNMR, UV‐Vis spectroscopy as well as X‐ray crystallography. Single‐crystal X‐ray diffraction analyses of two complexes lead to the elucidation of the structures and show that 1 possesses an asymmetric structure: one Pd atom is tetracoordinated by three sulfur atoms and one nitrogen atom to form PdS3N coordination sphere, the other Pd atom is tetracoordinated by three nitrogen atoms and one sulfur atom to form PdSN3 coordination sphere. The molecules of 1 are associated to 1‐D infinite linear chain by weak intermolecular Pd···S contacts in the crystal lattice. In 2 , the Pd atom lies on an inversion center and has a square‐planar coordination involving the S atoms from four MetzSH ligands. The two chloride ions are not involved in coordination, but are engaged in hydrogen bonding.  相似文献   

17.
The 1,3,5-triazine-water hydrogen bonding interactions have been investigated using the density functional theory B3LYP method and 6-31 ++G^** basis, obtaining one, two and seven energy minima of the ground states for the 1,3,5-triazine-water, 1,3,5-triazine-(water)2 and 1,3,5-triazine-(water)3 complexes respectively. The fully optimized geometries and binding energies were reported for the various stationary points. The global minima of 1,3,5-triazine-(water)2 and 1,3,5-triazine-(water)3 complexes have a hydrogen bond N…H-O and a chain of water molecules, terminated by a hydrogen bond O…H-C. The binding energies are 13.38, 39.52 and 67.79 kJ/mol for the most stable 1,3,5-triazine-water, 1,3,5-triazine-(water)2 and 1,3,5-triazine-(water)3 complexes respectively, after the basis set superposition error and zero point energy corrections. The H-O symmetric stretching modes of water in the complexes are red-shifted relative to those of the monomer water. In addition, the NBO analysis indicates that inter-molecule charge transfer is 0.02145 e, 0.02501 e and 0.02777 e for the most stable 1 : 1, 1 : 2 and 1 : 3 complexes between 1,3,5-triazine and water, respectively.  相似文献   

18.
New Hypersilanides of the Earth Metals Aluminium, Gallium, and Indium The dialkylaluminiumchlorides R2AlCl (with R = Me, Et; Me = CH3, Et = C2H5) react with base‐free lithium‐tris(trimethylsilyl)silanide (Li–Hsi; Hsi = –Si(SiMe3)3), forming the pyrophoric dialkyl aluminiumhypersilanides R2Al–Hsi. The methyl compound is dimeric in solid state (triclinic space group P1, Z = 1 dimer), as in Al2Me6 the association takes place by two Al–Me–Al bridges, forming a centrosymmetric molecule of approximately C2h point‐symmetry. Contrary to this (Me2GaCl)2 and Li–Hsi form a mixture of (MeGa(Hsi)Cl)2 and [Me3Ga–Hsi]Li. The monochloride again is a centrosymmetric, chlorine‐bridged dimer (monoclinic space group P21/n, Z = 2 dimers). The extremely air sensitive gallate can be prepared from GaMe3 and Li–Hsi (1 : 1 ratio), as well as the homologous [Me3Ga–Hsi]Na and [Me3Ga–Hsi]K from GaMe3 and the corresponding alkalimetal hypersilanides. The 1 : 1 toluene‐solvat of the sodium salt crystallizes in the orthorhombic space group Pbca (Z = 8) with polymeric zig‐zag‐chains, in which the toluene‐capped Na‐ions act as GaMe…Na…Me2Ga‐bridges between [Me3Ga–Hsi] anions. The reaction of InCl3 with Li–Hsi (1 : 3 ratio) mainly gives LiCl, metallic In and the “dihypersilyl” Hsi–Hsi. Ruby‐red (Hsi)2In–In(Hsi)2 could also be obtained in low yield and characterized by X‐ray structure elucidation (space group P21/c, Z = 4). The 1H, 13C, 29Si and 7Li NMR‐ and the vibrational spectra of the hypersilanides have been measured and discussed.  相似文献   

19.
The reactions of 2,11-diaza-difluoro-m-[3.3]-cyclophane with 1,3-bis(bromomethyl)-2-fluorobenzene or 2,6-bis(bromomethyl)-pyridine lead in one step to the respective 3 + 3-addition products 4 (yield 11%) and 5 (yield 27%), both of which are 48-membered macrocycles with nine or six potential CF-donor units. The nonafluoro ligand 4 appears not to form stable aggregates with alkali metal ions, while 5 gives a complex with two silver ions, which both are located on the inner periphery of the macrocyclic cavity. The coordination sphere of the two silver ions consists of three nitrogen atoms in a distorted trigonal-planar (Y-shape) environment as evidenced by an X-ray crystal structure. One of the Ag+ displays a short contact to an oxygen atom of the CF3SO3 counter ion, leading to a trigonal-pyramidal N3O-environment.  相似文献   

20.
Complexation of lithium ions by three chromoionophoric calix[4]arenes has been studied by 1H and 7Li NMR spectroscopy. The signalling unit of the chromoionophores is the N-methylpyridinium(methyleneimino) group in conjugation with a phenolic group of the calixarene ring while the coordination spheres contain esteric (ethoxycarbonylmethoxy) or etheric (ethoxy, propoxy) units. 1H NMR and NOESY measurements suggest the dominance of cone conformations of the calixarene rings with slight, solvent-dependent distortions. Complexation occurs only in the presence of a weak base. The interaction with lithium ions causes a broadening of both the 1H and 7Li NMR signals. Analysis of the chemical shifts in the three complexes indicates a different coordination environment for the lithium with the calixarene containing esteric groups from those having etheric groups. This explains the differences in the stabilities of the lithium complexes of the two types of calixarenes.  相似文献   

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