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1.
The reaction of diphenyltin dichloride with the binary Zintl phase K4Sn9 in the presence of excess lithium and 18‐crown‐6 in liquid ammonia led to the ammoniate [K(18‐crown‐6)(NH3)2]2Sn2Ph4 ( 1 ). The analogous reaction with K4Ge9 and potassium in the absence of further alkali metal ligands resulted in the compound [K2(NH3)12]Sn6Ph12 ? 4 NH3 ( 3 ). Cs6[Sn4Ph4](NH2)2 ? 8 NH3 ( 2 ) was prepared by reacting diphenyltin dichloride with a surplus of caesium in liquid ammonia. The low‐temperature single‐crystal structure determinations show all compounds to contain phenyl‐substituted polyanions of tin. Compound 1 is built from Sn2Ph anions consisting of Sn dumbbells with two Ph substituents at each Sn‐atom. Compound 2 contains cyclo‐Sn4Ph anions formed by a four‐membered tin ring in butterfly conformation with one Ph substituent at each Sn‐atom in an (all‐trans)‐configuration. Sn6Ph in 3 is a zig‐zag Sn6 chain with two substituents at each of the Sn‐atoms. Both 1 and 3 have molecular counter cations, in the latter case the unprecedented dinuclear potassiumammine complex [K2(NH3)12]2+ is observed. Compound 2 shows a complicated three‐dimensional network of Cs? Sn interactions.  相似文献   

2.
Several \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm C}_{{\rm 4}} {\rm H}_{{\rm\ 8}} } \right]_{}^{_.^ + } $\end{document} ion isomers yield characteristic and distinguishable collisional activation spectra: \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm 1-butene} } \right]_{}^{_.^ + } $\end{document} and/or \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm 2-butene} } \right]_{}^{_.^ + } $\end{document} (a-b), \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm isobutene} } \right]_{}^{_.^ + } $\end{document} (c) and [cyclobutane]+ (e), while the collisional activation spectrum of \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm methylcyclopropane} } \right]_{}^{_.^ + } $\end{document} (d) could also arise from a combination of a-b and c. Although ready isomerization may occur for \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm C}_{{\rm 4}} {\rm H}_{{\rm 8}} } \right]_{}^{_.^ + } $\end{document} ions of higher internal energy, such as d or ea, b, and/or c, the isomeric product ions identified from many precursors are consistent with previously postulated rearrangement mechanisms. 1,4-Eliminations of HX occur in 1-alkanols and, in part, 1-buthanethiol and 1-bromobutane. The collisional activation data are consistent with a substantial proportion of 1,3-elimination in 1- and 2-chlorobutane, although 1,2-elimination may also occur in the latter, and the formation of the methylcycloprpane ion from n-butyl vinyl ether and from n-butyl formate. Surprisingly, cyclohexane yields the \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm linear butene} } \right]_{}^{_.^ + } $\end{document} ions a-b, not \documentclass{article}\pagestyle{empty}\begin{document}$ \left[{{\rm cyclobutane} } \right]_{}^{_.^ + } $\end{document}, e.  相似文献   

3.
Building on previous single crystal X‐ray structure determinations for the group 1 salts of complex thiosulfate/univalent coinage metal anions previously defined for (NH4)9AgCl2(S2O3)4, NaAgS2O3·H2O and Na4[Cu(NH3)4][Cu(S2O3)2]·NH3, a wide variety of similar salts, of the form , M1 = group 1 metal cation, M2 = univalent coinage metal cation (Cu, Ag), (X = univalent anion), most previously known, but some not, have been isolated and subjected to similar determinations. These have defined further members of the isotypic, tetragonal series, for M1 = NH4, M2 = Cu, Ag, X = NO3, Cl, Br, I, together with the K/Cu/NO3 complex, all containing the complex anion [M2(SSO3)4]7? with M2 in an environment of symmetry, Cu, Ag‐S typically ca. 2.37, 2.58Å, with quasi‐tetrahedral S‐M‐S angular environments. Further salts of the form , n = 1‐3, have also been defined: For n = 3, M2 = Cu, M1/x = K/2.25 or 1 5/6, NH4/6, (and also for the (NH4)4Na/4H2O·MeOH adduct) the arrays take the form with distorted trigonal planar CuS3 coordination environments, Cu‐S distances being typically 2.21Å, S‐Cu‐S ranging between 105.31(4)–129.77(4)°; the silver counterparts take the form for M1 = K, NH4. For n = 2, adducts have only been defined for M2 = Ag, the anions of the M1 = Na, K adducts being dimeric and polymeric respectively: Na6[(O3SS)2Ag(μ‐SSO3)2Ag(SSO3)]·3H2O, K3[Ag(μ‐SSO3)2](∞|∞)·H2O; a polymeric copper(I) counterpart of the latter is found in Na5Cu(NO3)2(S2O3)2 ≡ 2NaNO3·Na3[Cu(μ‐SSO3)2](∞|∞). For n = 1, NaAgS2O3, the an‐ and mono‐ hydrates, exhibit a two‐dimensional polymeric complex anion in both forms but with different contributing motifs. (NH4)13Ag3(S2O3)8·2H2O takes the form (NH4)13[{(O3SS)3Ag(μ‐SSO3)}2Ag], a linearly coordinated central silver atom linking a pair of peripheral [Ag(SSO3)4]7? entities. In Na6[(O3SS)Ag(μ‐SSO3)2Ag(SSO3)]·3H2O, the binuclear anions present as Ag2S4 sheets, the associated oxygen atoms being disposed to one side, thus sandwiching layers of sodium ions; the remarkable complex Na5[Ag3(S2O3)4](∞|∞)·H2O is a variant, in which one sodium atom is transformed into silver, linking the binuclear species into a one‐dimensional polymer. In (NH4)8[Cu2(S2O3)5]·2H2O a binuclear anion of the form [(O3SS)2Cu(μ‐S.SO3)Cu(SSO3)2]8? is found; the complex (NH4)11Cu(S2O3)6 is 2(NH4)2(S2O3)·(NH4)7[Cu(SSO3)4]. A novel new hydrate of sodium thiosulfate is described, 4Na4S2O3·5H2O, largely describable as sheets of the salt, shrouded in water molecules to either side, together with a redetermination of the structure of 3K2S2O3·H2O.  相似文献   

4.
《Electroanalysis》2006,18(10):993-1000
A composite film modified electrode containing a Keggin‐type heteropolyanion, H3(PMo12O40)?H2O, was fabricated with 3‐aminopropyltrimethoxysilane (APMS) attached on an electrochemically activated glassy carbon (GC) electrode through the formation of C? O? Si bond. PMo12O was then complexed with APMS through the electrostatic interaction between the phosphate groups of PMo12O and amine groups of APMS (PMo12O ‐APMS). XPS and cyclic voltammetry were employed for characterization of the composite film. The PMo12O ‐APMS modified electrode showed three reversible redox pairs with smaller peak‐separation and was stable in the larger pH range compared with that in a solution phase. The catalytic properties of the modified electrode for the reduction of ClO , BrO , and IO were studied and the modified electrode exhibited good electrocatalytic activities for the three anions. The experimental parameters, such as pH, temperature, and the applied potential were optimized. The detection limits were determined to be 7.0±0.35 μM, 4.0±0.17 μM, and 0.1±0.04 μM for ClO , BrO , and IO , respectively. The modified electrode was applied to natural water samples for the detection of ClO , BrO , and IO .  相似文献   

5.
In the presence of Bu4NBr acting as phasetransfer reagent, organothiophosphoryl polyoxotungstate derivatives α-[RP(S)]2PW9O54^5- (R=C6Hs, C6H11) have been obtained by reaction of the trivacant β-[PW9O34]^9- anions with electrophilic C6H5P(S)Cl2 or C6H11P(S)Cl2 in acetonitrile. These new organic-inorganic hybrid anions have been characterized by elemental analysis, IR, ^31P and ^183W NMR spectroscopy. The collective application of the spectroscopy data of these new species indicates that the hybrid anion consists of an α-[PW9O34] framework on which are grafted two RP(S) groups through P-O-W bridges. The five-line ^183W spectra indicate that the hybrid anions possess Cs symmetry in acetonitrile.  相似文献   

6.
The syntheses and X‐ray single‐crystal low‐temperature structures of the four new ammoniates [Li(NH3)4]3As7?NH3 ( 1 ), [Rb(18‐crown‐6)]3As7?8 NH3 ( 2 ), Cs3As7?6 NH3 ( 3 ), and (Ph4P)2CsAs7?5 NH3 ( 4 ) are reported. The compounds were obtained by either direct reduction of As with Li/Cs in liquid NH3, solvation of Cs4As6/Rb4As6 in liquid NH3, or by extraction of solid Cs3As7. While compound 1 contains isolated As polyanions, As? M contacts (M=Na?Cs) lead to neutral [Rb(18‐crown‐6)]3As7 units in 2 , a three‐dimensional, extended network in 3 , and one‐dimensional, infinite [CsAs7]2? chains in 4 , respectively.  相似文献   

7.
The reactions of metastable $ {\rm CH}_{\rm 2} = {\rm CHCH =}\mathop {{\rm OCH}_{\rm 3}}\limits^{\rm +} $ oxonium ions generated by alkyl radical loss from ionized allylic alkenyl methyl ethers are reported and discussed. Three main reactions occur, corresponding to expulsion of H2O, C2H4/CO and CH2O. There is also a very minor amount of C3H6 elimination. The mechanisms of these processes have been probed by 2H- and 13C-labelling experiments. Special attention is given to the influence of isotope effects on the kinetic energy release accompanying loss of formaldehyde from 2H-labelled analogues of $ {\rm CH}_{\rm 2} = {\rm CHCH =}\mathop {{\rm OCH}_{\rm 3}}\limits^{\rm + } $. Suggestions for interpreting these reactions in terms of routes involving ion–neutral complexes are put forward.  相似文献   

8.
The compounds Ae3Sn4?xBi1+x (Ae = Sr, Ba) with x < 1 have been synthesized by solid‐state reactions in welded Nb tubes at high temperature. Their structures were determined by single crystal X‐ray diffraction studies to be tetragonal; space group I4/mcm (No. 140); Z = 4, with a = 8.968(1) Å, c = 12.859(1) Å for Sr3Sn3.36Bi1.64(3) ( 1 ) and a = 9.248(2), c = 13.323(3) Å for Ba3Sn3.16Bi1.84(3) ( 2 ). The structure consists of two interpenetrating networks formed by a 3D Ae6/2Bi substructure (anti‐ReO3 type) forming the host, and layers of interconnected four‐member units [Sn4?xBix] with “butterfly”‐like shape as the guest. According to the Zintl‐Klemm concept, the compounds are slightly electron deficient and will be charge balanced for x = 1. The electronic structures of Ae3Sn4?xBi1+x calculated by the TB‐LMTO‐ASA method indicate that the compounds correspond to ideal semiconducting Zintl phases with a narrow band gap for x = 1 (zero‐gap semiconductor). The origin of the slight deviation from the optimal electron count for a valance compound is discussed.  相似文献   

9.
The six‐membered ring Hg3Te3 of [Hg3Cl3(μ‐TePh)3]·2 DMSO {(Ph = C6H5; DMSO = (CH3)2SO} was opened by redissolution with DMSO, reacting with Co[Hg(SCN)4] and affording polymeric . The monoclinic novel compound belong to the space group P21/n and assembles in a bidimensional lattice tetrahedral HgII(SCN)2Te2‐ and octahedral CoII(NCS)4(DMSO)2‐chains linked trough SCN bridges along the crystallographic axis b and diagonally to the ac axes. The structure of [(DMSO)2Co(NCS)4(Hg—TePh)2]n is limited by the DMSO ligands in the axial positions of the Co‐octahedrons.  相似文献   

10.
The results of some 3C and 2H labelling experiments plus some measurements of reaction thermochemistry and translational energy releases, permit a significant simplification of the mechanistic pathways by which [C3H7O]+ ions of structure fragment by loss of C2H4. The relationships between these ions and some of their isomeric forms are explored and clarified.  相似文献   

11.
The formation and crystal structures of bis(1‐naphthyl) diselenide ( 1 ) and bis{[2‐(N,N‐dimethylamino)methyl]phenyl} tetraselenide ( 2 ) are described. Whereas 1 can be produced in good yields, 2 is formed only as a minor product together with the known main product, bis{[2‐(N,N‐dimethylamino)methyl]phenyl} diselenide. The composition of the reaction mixture is semi‐quantitatively estimated by 77Se NMR spectroscopy and DFT calculations. The effect of the n2→σ*(Se–Se) and π→σ*(Se–Se) secondary bonding interactions on the Se–Se bonds is discussed both by DFT calculations and comparison with literature, as available. The bromination of 1 yields monomeric (1‐naphthyl)selenenyl bromide ( 3 ) in good yields. That of the reaction mixture of (C6H4CH2NMe2)Sex (x = 2–4) and Se8 afforded (C6H4CH2NMe2H)2[SeBr4] ( 4 ) and (C6H4CH2NMe2H)2[SeBr6] ( 5 ) in addition to (C6H4CH2NMe2)SeBr, which has been previously reported.  相似文献   

12.
Two new glutarato bridged coordination polymers {[Mn(phen)]2(C5H6O4)4/2} ( 1 ) and {[Zn(phen)(H2O)](C5H6O4)2/2}· H2O ( 2 ) were structurally characterized on the basis of single crystal X‐ray diffraction data. Crystal data: ( 1 ) P2/c (no. 13), a = 10.340(2)Å, b = 10.525(2)Å, c = 13.891(2)Å, β = 98.31(1)°, U = 1495.9(5)Å3, Z = 2; ( 2 ) P21/n (no. 14), a = 6.738(1)Å, b = 25.636(3)Å, c = 10.374(1)Å, β = 106.13(1)°, U = 1721.4(4)Å3, Z = 4. Complex 1 consists of 1D ribbon‐like {[Mn(phen)]2(C5H6O4)4/2} chains, in which the [Mn(phen)] units were interlinked by glutarato ligands to generate 8‐ and 16‐membered rings. The Mn atoms are octahedrally coordinated by two N atoms of one phen ligand and four O atoms of three glutarato ligands with d(Mn‐N) = 2.270, 2.276Å, d(Mn‐O) = 2.114—2.283Å. Through the interchain π‐π stacking interactions, the 1D chains are assembled into 2D puckered layers, which are further held together by interlayer π‐π stacking interactions into a 3D network. Complex 2 is built up by 1D {[Zn(phen)(H2O)](C5H6O4)2/2} linear chains and hydrogen bonded H2O molecules. The Zn atoms are coordinated by two N atoms of one phen ligand and three O atoms of one H2O molecule and two glutarato ligands to form slightly elongated trigonal bipyramids with the water O atom and one phen N atom at the apical positions (d(Zn‐N) = 2.101, 2.168Å, d(Zn‐O) = 1.991—2.170Å). The 1D linear chains result from [Zn(phen)(H2O)] units bridged by bis‐monodentate glutarato ligands. The resulting 1D chains are assembled by π‐π stacking interactions into 2D layers, between which the hydrogen bonded H2O molecules are situated.  相似文献   

13.
14.
《Electroanalysis》2006,18(18):1838-1841
The immobilization of tris(2,2'‐bipyridyl)ruthenium(II) [Ru(bpy) ] in a TiO2/Nafion nanocomposites membrane modified glassy carbon electrode (GCE) was achieved via both an ion‐exchange process and hydrophobic interactions .The surface‐confined Ru(bpy) shows good electrochemical and photochemical activities. The Ru(bpy) underwent reversible surface process and reacted with chlorphenamine maleate (CPM) to produce electrochemiluminescence. The modified electrode was used for the ECL determination of CPM. It showed good linearity in the concentration range from 2×10?8 g/mL to 1×10?6 g/mL (R=0.9995) with a detection 6×10?9 g/mL (S/N=3). The relative standard derivation (n=11) was 2%. This method is developed for the determination of CPM with simplicity and high sensitivity.  相似文献   

15.
Using phosphoryl chloride as a substrate, a family of 1,3,2‐bis(arylamino) phospholidine, 2‐oxide of the general formula ; (X=Cl, 6a ; X=NMe2, 1b ; X=N(CH2C6H5)(CH3), 2b ; X=NHC(O)C6H5, 3b ; X=4Me‐C6H4O, 4b ; X=C6H5O, 5b ; X=NHC6H11, 6b ; X=OC4H8N, 7b ; X=C5H10N, 8b ; X=NH2, 9b ; X=F, 10b and Ar=4Me‐C6H4) was prepared and characterized by 1H, 19F, 31P and 13C NMR and IR spectroscopy, and elemental analysis. A general and practical method for the synthesis of these compounds was selected. The structures of 6a and 2b were determined by single‐crystal X‐ray diffraction techniques. The low temperature NMR spectra of 2b revealed the restricted rotation of P‐N bond according to two independent molecules in crystalline lattice.  相似文献   

16.
Pb5I2P28 is the first compound containing a former unseen [P3I2]4+ unit, connecting two crystallographically independent adjacent [PbP14]2? polyphosphide strands. The polyanion substructure is closely related to the one realized in the HgPbP14 structure type, with a homo‐nuclear coordination of the cations to the polyanions. It has been prepared by using the mineralizator concept for polyphosphides from the elements and PbI2 as the mineralizator species. The new polyphosphide has a pronounced tendency to form easy cleavable, needle shaped crystals featuring massive stacking vaults. Nevertheless, a single crystal structure determination was possible from inter‐grown crystals. Pb5I2P28 crystallizes monoclinically in the space group P21/n (No. 14) with lattice parameters of a = 9.792(2), b = 17.717(2), c = 19.191(3) Å, β = 96.39(1)°, V = 3308.6(8) Å3. Depending on the preparation route, the aspect ratio of the needle shaped crystals can be varied.  相似文献   

17.
Single crystalline , (Tz*) = 1,2,3‐triazolate anion, C2H2N3, was obtained by the reaction of terbium metal with the amine 1H‐1,2,3‐triazole. As no additional solvent was used, the formation of a homoleptic framework without additional co‐ligands is accessible. Furthermore molecular hydrogen is produced. is a 2‐dimensional framework with a (6,6) topology including (Tz*) double bridges. The structure can be deduced from a basic structure type as it adopts the AlCl3 structure with the triazolate ligands establishing the package. (Tz*) thus function as μ‐η12/μ‐η21 linkers between trivalent terbium ions that have a C.N. of nine. The framework exhibits an exceptional thermal stability up to 380 °C considering the three neighbouring nitrogen atoms of the triazolate ligands. At this point the framework decomposes in one single exothermic step under release of N2.  相似文献   

18.
The reactions of the Zintl phase K2Cs2Sn9 with elemental tellurium and selenium in ethylenediamine have been investigated. From the reaction of K2Cs2Sn9 with elemental tellurium [K‐(2,2,2‐crypt)]4Te6Te4 ( 2 ) and [K‐(2,2,2‐crypt)]2Sn2Te3 ( 3 ) were obtained, whereas the reaction of K2Cs2Sn9 with elemental selenium led to the formation of [K‐(2,2,2‐crypt)]2Sn(Se4)3 ( 4 ) and [K‐(2,2,2‐crypt)]2Cs2Sn2Se6·2en ( 5 )1). Compounds 2 , 4 , 5 have been characterized by single crystal X‐ray structure determination.  相似文献   

19.
The network compound , (Tz? = 1,2,4‐triazolate anion, C2H2N3?, TzH = 1,2,4‐1H‐triazole, C2H3N3), was obtained as pink single crystals by the reaction of the holmium metal with a melt of the amine 1,2,4‐1H‐triazole. No additional solvent was used. The compound is an unexpected example of a 2D‐linked network structure as other lanthanides give 3D‐frameworks and MOFs with 1,2,4‐1H‐triazole instead. This illustrates that the series of lanthanides yields very different results in attempts to create MOF structures. In the triazolate ligands Tz? function both as μ‐η12 linkers as well as η1 end on ligands. The latter coordination mode is also found for additional triazole molecules. C.N. is nine for holmium(III). The layers exhibit a system of intra and inter layer hydrogen bonding and to triazole molecules from the melt reaction intercalated in‐between the layers. The product was investigated by X‐ray single crystal analysis, Mid IR, Far IR and Raman spectroscopy, and with DTA/TG regarding its thermal behaviour.  相似文献   

20.
The charge stripping mass spectra of [C2H5O]+ ions permit the clear identification of four distinct species: \documentclass{article}\pagestyle{empty}\begin{document}${\rm CH}_{\rm 3} - {\rm O - }\mathop {\rm C}\limits^{\rm + } {\rm H}_{\rm 2}$\end{document}, \documentclass{article}\pagestyle{empty}\begin{document}${\rm CH}_{\rm 3} - \mathop {\rm C}\limits^{\rm + } {\rm H - OH}$\end{document}, and \documentclass{article}\pagestyle{empty}\begin{document}${\rm CH}_{\rm 2} = {\rm CH - }\mathop {\rm O}\limits^{\rm + } {\rm H}_{\rm 2}$\end{document}. The latter, the vinyloxonium ion, has not been identified before. It is generated from ionized n-butanol and 1,3-propanediol. Its heat of formation is estimated to be 623±12 kJ mol?1. The charge stripping method is more sensitive to these ion structures than conventional collisional activation, which focuses attention on singly charged fragment ions.  相似文献   

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