共查询到20条相似文献,搜索用时 15 毫秒
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Wan L Pi C Zhang L Zheng W Weng L Chen Z Zhang Y 《Chemical communications (Cambridge, England)》2008,(19):2266-2268
Treatment of H[3,5-Ph2dp] (Hdp = 1H-1,2,4-diazaphosphole) with nBuLi or KH, or the reaction of K[3,5-tBu2dp] with an excess amount of O2, afforded the dimeric species [(eta2,eta1-3,5-Ph2dp)Li(THF)2]2 and the polymeric complexes [(eta2:eta4-3,5-Ph2dp)K(Et2O2]n, and [[(eta2:eta5-3,5-tBu2dp)K(THF)][eta2(N,N)-eta3(O,P,O)-3,5-tBu2dp-(O,O)O2K]]n, respectively. 相似文献
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Treatment of [[Ti(eta(5)-C(5)Me(5))(mu-NH)](3)(mu(3)-N)] with alkali-metal bis(trimethylsilyl)amido derivatives [M[N(SiMe(3))(2)]] in toluene affords edge-linked double-cube nitrido complexes [M(mu(4)-N)(mu(3)-NH)(2)[Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3)-N)]](2) (M = Li, Na, K, Rb, Cs) or corner-shared double-cube nitrido complexes [M(mu(3)-N)(mu(3)-NH)(5)[Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3)-N)](2)] (M = Na, K, Rb, Cs). Analogous reactions with 1/2 equiv of alkaline-earth bis(trimethylsilyl)amido derivatives [M[N(SiMe(3))(2)](2)(thf)(2)] give corner-shared double-cube nitrido complexes [M[(mu(3)-N)(mu(3)-NH)(2)Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3)-N)](2)] (M = Mg, Ca, Sr, Ba). If 1 equiv of the group 2 amido reagent is employed, single-cube-type derivatives [(thf)(x)[(Me(3)Si)(2)N]M[(mu(3)-N)(mu(3)-NH)(2)Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3)-N)]] (M = Mg, x = 0; M = Ca, Sr, Ba, x = 1) can be isolated or identified. The tetrahydrofuran molecules are easily displaced with 4-tert-butylpyridine in toluene, affording the analogous complexes [(tBupy)[(Me(3)Si)(2)N]M[(mu(3)-N)(mu(3)-NH)(2)Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3)-N)]] (M = Ca, Sr). The X-ray crystal structures of [M(mu(3)-N)(mu(3)-NH)(5)[Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3)-N)](2)] (M = K, Rb, Cs) and [M[(mu(3)-N)(mu(3)-NH)(2)Ti(3)(eta(5)-C(5)Me(5))(3)(mu(3))-N)](2)] (M = Ca, Sr) have been determined. The properties and solid-state structures of the azaheterometallocubane complexes bearing alkali and alkaline-earth metals are discussed. 相似文献
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Izod K Watson JM Clegg W Harrington RW 《Dalton transactions (Cambridge, England : 2003)》2011,40(44):11712-11718
Treatment of the secondary phosphine {(Me(3)Si)(2)CH}PH(C(6)H(4)-2-SMe) with BH(3)·SMe(2) gives the corresponding phosphine-borane {(Me(3)Si)(2)CH}PH(BH(3))(C(6)H(4)-2-SMe) (9) as a colourless solid. Deprotonation of 9 with n-BuLi, PhCH(2)Na or PhCH(2)K proceeds cleanly to give the corresponding alkali metal complexes [[{(Me(3)Si)(2)CH}P(BH(3))(C(6)H(4)-2-SMe)]ML](n) [ML = Li(THF), n = 2 (10); ML = Na(tmeda), n = ∞ (11); ML = K(pmdeta), n = 2 (12)] as yellow/orange crystalline solids. X-ray crystallography reveals that the phosphido-borane ligands bind the metal centres through their sulfur and phosphorus atoms and through the hydrogen atoms of the BH(3) group in each case, leading to dimeric or polymeric structures. Compounds 10-12 are stable towards both heat and ambient light; however, on heating in toluene solution in the presence of 10, traces of free phosphine-borane 9 are slowly converted to the free phosphine {(Me(3)Si)(2)CH}PH(C(6)H(4)-2-SMe) (5) with concomitant formation of the corresponding phosphido-bis(borane) complex [{(Me(3)Si)(2)CH}P(BH(3))(2)(C(6)H(4)-2-SMe)]Li (14). 相似文献
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Swisłocka R Regulska E Samsonowicz M Hrynaszkiewicz T Lewandowski W 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(13-14):2966-2973
The vibration (FT-IR, FT-Raman), electronic (UV-Vis) and NMR (1H and 13C) spectra for 3-aminobenzoic acid and its alkali metal salts were recorded. The influence of lithium, sodium, potassium, rubidium and cesium on the electronic system of the 3-aminobenzoic acid was studied. The assignment of the vibration spectra was done. Characteristic shifts of band wavenumbers and changes in band intensities along the metal series were observed. Good correlation between the wavenumbers of the vibrational bands in the IR and Raman spectra for 3-aminobenzoates and ionic potential, electronegativity, atomic mass and affinity of metal cations were found. The chemical shifts of protons (1H NMR) and carbons (13C NMR) in the series of studied alkali metals were also observed. Optimized geometrical structures of studied compounds were calculated by ab initio and density functional methods. 相似文献
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《Journal of Coordination Chemistry》2012,65(16):1405-1412
The crystal structures of sodium 4-amino-2-hydroxybenzoate dihydrate [NaL·2H2O, L?= C6H3(NH2)(OH)COO] and potassium 2-aminobenzoate monohydrate [KL*·H2O, L*?=?C6H4(NH2)COO] were determined by X-ray diffraction methods. The compound NaL·2H2O crystallizes in the monoclinic system, space group P21/c with a?=?8.820(2), b?=?14.632(3), c?=?6.948(2)?Å, β?=?97.88(3)°. The structure consists of sodium ion pairs joined together by tridentate 4-amino-2-hydroxybenzoate moieties creating a polymeric chain. In the metal centres, two water molecules bridge the sodium atoms. Five oxygen atoms and one nitrogen atom form a distorted octahedral environment. The compound KL*·H2O crystallizes in the monoclinic system, space group P21/c with a?=?14.684(3), b?=?7.618(2), c?=?7.512(2)?Å, β?=?96.95(3)°. The structure consists of octacoordinated potassium atoms bonded with three water molecules and five carboxylate oxygen atoms. Water molecules appear as bridging ligands. The 2-aminobenzoate ligand acts as a pentadentate ligand with the molecular network stabilized by hydrogen bonds. Among the polymeric chains in both structures appear noncovalent interactions of type N?H···X. 相似文献
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Complexes having the general formula ML.HL, where M = Na, K, Rb or Cs and HL = quinaldinic acid, have been obtained. The isolation of adducts in the solid state appeared to be favoured by increase in atomic radius, and hence decrease in ionisation potential of the metal. Attempts to synthesise similar adducts of picolinic acid N-oxide and quinaldinic acid N-oxide did not succeed. Complexes have been characterised by elemental analyses, thermal, IR spectral and solution studies. Our findings suggest that pK value of the ligands cannot be regarded a dominant factor in the synthesis and isolation of alkali metal complexes. 相似文献
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Field evaporation from solution has been used to detect crown-ether 15K5 and 18K6 coordination compounds formed with Na+, K+, Cs+, Ba2+ and Ca2+ in aqueous solution, both hydrated and unhydrated; the Ca2+·18K6·(H2O)n (n=0, 1, 2,...) compounds have been observed before. 18K6 present in the solution greatly increases the yields of 18K6 compounds with the dissociation products from Ba(NO3)2. The detection limits for 15K5 and 18K6 combined with Na+, K+, and Cs+ are approximately the same at 10–7 g.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 24, No. 2, pp. 239–242, March–April 1988. 相似文献
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1. | The interaction of borohydrides of the alkali and alkaline-earth metals (Li, Na, K, Mg, Ca, and Sr) with dihorane in diglyme medium at 0° and an initial pressure of B2H6 no higher than 600 mm was studied. |
2. | It was established according to the data of the IR spectrum that all the investigated borohydrides, with the exception of calcium borohydride, react with diborane in diglyme with the formation of diborohydrides. |
3. | In the interaction of calcium borohydride with B2H6, the addition of borane (BH3) occurs at one of the two BH4 groups, with the formation of the compound CaBH4B2H7 ·2DG. |
4. | LiB2H7 · 2DG, NaB2H7 · 2DG, and CaBH4B2H7 · 2DG were isolated in the individual state. |
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M. Ambrová J. Jurišová V. Danielik J. Gabčová 《Journal of Thermal Analysis and Calorimetry》2008,91(2):569-573
The solubilities of lanthanum oxide in LiF, NaF, KF and eutectic melt LiF-NaF-KF (46.5 mole% LiF; 11.5 mole% NaF and 42.0
mole% KF) were measured in order to find the suitable electrolyte for electrodeposition of lanthanum. Solidus-liquidus lines
were obtained by the method of thermal analysis. The solubility of lanthanum oxide in alkali fluorides is rather low and decreases
in the order LiF>NaF>KF.
It was found that lanthanum oxide reacts with the components of the melt. LaOF and alkali metal oxide are formed during dissolution
of La2O3 in the melt. 相似文献
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The minimal energy conformations of o-benzosemiquinone anion radicals in the solvents containing the alkali metals and the alkali earth metals were calculated by using the INDO method and the molecular geometry adjusting method. Our previous calculations of o-benzosemiquinone anion radical in the lithium ion solution showed that the total energy of the minimal energy conformation in the case of the assignment |A3| > |A4| were lower by approximately 320 kcal/mol than that in the case of the assignment |A3| > |A4|. Therefore, the calculations of the minimal energy conformations of o-benzosemiquinone anion radicals in the metal ion solutions were carried out in the cases of the assignment |A3| > |A4|. The conformations in both assignments A3 < A4 < 0 and (A3 < 0 < A4 and |A3| > |A4|) were calculated. Although the metal ions were not explicitly contained in the molecular geometries, the minimal energy conformations are considered to be close to the real minimal energy conformations of o-benzosemiquinone anion radicals in the metal ion solutions. The C? O bond lengths has a good positive rank correlation with the stabilities of o-benzosemiquinone radicals in the divalent metal ion solutions and the bond angles ∠C3C4H4 had a good negative rank correlation with those stabilities. 相似文献
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K. I. Selezneva 《Russian Chemical Bulletin》1966,15(7):1236-1238
Conclusions A new method for obtaining pyroperoxoniobates of the alkali metalswith the composition(Na, K)4Nb2O11 · 2H2O has been developed.The solid salts (Na, K)4Nb2O11 · 2H2O are stable above 100°. They decompose completely 300° with the formation of pyro salts having the composition (Na, K)4Nb2O7 of reagent purity.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1281–1283, July, 1966. 相似文献
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Layfield RA García F Hannauer J Humphrey SM 《Chemical communications (Cambridge, England)》2007,(47):5081-5083
Alkali metal complexes of two types of ansa-tris(allyl) ligand are reported; a monoanionic ansa-tris(allyl) ligand containing tin(II) is formally valence isoelectronic to the cyclopentadienyl ligand and a trianionic ansa-tris(allyl) ligand containing silicon(IV) is formally valence isoelectronic to an ansa-metallocene ligand; the potential wider use of these tripodal ligands in coordination chemistry is discussed. 相似文献
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