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Bis‐trimethylamine‐ethynyl‐di‐bis(trifluoromethyl)borane [Me3N(CF3)2BCCB(CF3)2NMe3] ( 1 ) has been prepared from trimethylamine‐ethynyl‐bis(trifluoromethyl)borane, [HCCB(CF3)2NMe3], and dimethylamino‐bis(trifluoromethyl)borane, (CF3)2BNMe2. The structure of 1 has been determined by x‐ray crystallography. In the solid state the molecule possesses crystallographic Ci symmetry. The acetylenic attachment to the boron atom is characterized by a short B–C bond length of 1.565(4) Å and an essentially linear B–C–C′ bond angle of 178.1(4)°.  相似文献   

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The reaction of Ph2P(S)N(SiMe3)2 with potassium tert-butoxide in a 1:1 molar ratio produces K[Ph2P(S)NSiMe3], which was converted to the AsPh4+ salt by metathesis with [AsPh4]Cl. The X-ray crystal structure of [AsPh4][Ph2P(S)NSiMe3] · 0.5 THF consists of noninteracting AsPh4+ and Ph2P(S)NSiMe3? ions with d(P? S) = 1.980(4) Å and d(P? N) = 1.555(8) Å. The PNSi bite angle in the anion is 136.3(5)°. Electrophilic attack by Ph2P(S)Cl occurs at the sulfur atom of Ph2P(S)NSiMe3?. The oxidation of the anion with iodine produces a disulfide which regenerates K[Ph2P(S)NSiMe2] upon treatment with potassium tert-butoxide.  相似文献   

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A thione-thiol structure was established for 2-mercapto-5-thiono[4,2,1]triazolino[3,4-b] [1,3,4]thiadiazole in accordance with calculations of the π-bonding and solvation energies by the Pariser-Parr-Pople method and also on the basis of a study of the IR and UV spectra. It follows from a determination of the ionization constants that this compound is a strong acid.  相似文献   

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Abstract

The heterometallic polymeric cluster Na2[AlW3O4 (O2CEt)8]2 (1) has been prepared by reaction of W(CO)6 and NaWO4·2H2O with AlCl3 at 120°C in propionic anhydride and characterized by X-ray crystallography, with the following crystal data: triclinic, space group P1, a = 12.205(5), b = 13.032(4), c = 13.925(3) Å, α = 90.21(3)°, β = 109.53(5)°, γ = 117.26(6)°, V = 1822.8(1)Å3, Z = 1, R = 0.038 and Rw = 0.101. The structure consists of two triangular [W3O4(O2CEt)8]4? cluster unit, which act as polydenate ligands to link Al3+ and Na+ ions forming a one–dimensional chain structure. IR spectra show characteristic [W3O4]4+ bands at 746–815 cm?1. Thermal analysis reveals that the complex is air stable up to 250°C. Cluster 1 decomposes in hot aqueous 2 M HCl solution to produce discrete [W3O4]4+ units.  相似文献   

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合成了N-苯基-1,7-二硒杂-4-氮杂-[7]二茂铁环蕃(1),并用核磁、质谱、单晶X-射线衍射进行了表征。晶体结构测试结果表明1是属于正交晶系的Ibca空间群,晶胞参数a=0.95474(2)nm,b=0.95958(2)nm,c=7.8590(2)nm,其中晶胞参数c值在N-Se杂大环中很少见。光谱研究显示1仅对Hg2+和Cu2+的加入产生响应,表现为紫外最大吸收峰的红移和荧光淬灭。  相似文献   

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Pushing the limits of coordination chemistry : The most weakly coordinated silver complexes of the very weakly coordinating solvents dichloromethane and liquid sulfur dioxide were prepared. Special techniques at low temperatures and the use of weakly coordinating anions allowed structural characterization of [Ag(OSO)][Al{OC(CF3)3}4], [Ag(OSO)2/2][SbF6], and [Ag(Cl2CH2)2][SbF6] (see figure). An investigation of the bonding shows that these complexes are mainly stabilized by electrostatic monopole–dipole interactions.

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Condensation of 3,4-dihydro-6,7-dimethoxyisoquinoline ( 4 ) with 4-methylnicotinoyl chloride ( 12 ) in refluxing pyridine gives 5,6,13,13a-tetrahydro-2,3-dimethoxy-8H-isoquino[2,1-b][2,7] naphthyridin-8-one ( 11 ), along with some of its 13,13a-didehydro derivative 7 . A similar reaction of 4 with 4-(chloromethyl)nicotinoyl chloride ( 14 ) affords, in addition to 7 , the isomeric product 10,11-dihydro-7,8-dimethoxy-13H-pyrido[4′,3′:3,4]pyrrolo[2,1- b][3]benzazepin-13-one ( 3 ). Analogous pairs of products are obtained from 3,4-dihydro-6,7-(methylenedioxy)- and 3,4-dihydro-6,7,8-trimethoxy-isoquinolines ( 15 and 18 , resp.). The structure of 3 was established by extensive NMR data and confirmed by single-crystal X-ray studies. Structure 7 has the ring system of the Alangium alkaloids like alangimarinc ( 1 ), while the isomeric ring system 3 is predicted to be present in nature on biogenetic reasoning.  相似文献   

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Photoelectron Spectra and Molecular Properties. 132. Trifluoromethylsulfane and Derivatives F3CSX (X ? CF3, Cl, Br, I) The He(I) photoelectron spectra of trifluoromethylsulfane F3CSH and its derivatives F3CSX (X ? CF3, Cl, Br, I) are assigned by Koopmans' correlations, IE = ?ε, with MNDO eigenvalues, by radical cation state comparison and based on resolved vibrational fine structures, which can' be discussed by MNDO FORCE calculations. The spin/orbit splitting in F3CSI can be approximated by additional ITEREX-85 calculations. Gasphase thermolysis of the trifluoromethylhalogensulfanes F3CSX at 10?4 mbar yields decomposition temperatures, which decrease from X ? Cl to I, and as fragmentation products of presumably radical intermediates, in addition to the respective halogens X2 and F2C?S, also F3CX as well as S2 and CS2 (X ?Cl, Br) are PE spectroscopically detected.  相似文献   

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Photoelectron Spectra and Molecular Properties. 133. Trifluoromethyldisulfane and Derivates F3CSSX (X?CF3, F, Cl, Br) The He(I) photoelectron spectra of trifluoromethyldisulfane F3CSSH and its derivatives F3CSSX (X?CF3, F, Cl, Br) are assigned by Koopmans correlations, IE = ?ε, with MNDO eigenvalues and by radical cation state comparison. Of special interest are the n/n splittings, which amount to 1.15 eV F3C? SS? F or 0.87 eV in F3? SS? Cl, and the dependance of which on the dihedral angle ω(XS? SX), on the SS bond length and on the acceptor effect of the F3C substituents is discussed.  相似文献   

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A series of 3-pyridinyl-6-aryl-1, 2, 4-triazolo[3, 4-b][1, 3, 4]thiadiazoles(PATT) were prepared, the structures were confirmed by 1R and ^1H NMR spectra. The results of cyclic voltammetry measurements imply that all these compounds have a higher electron affinity (EA) than 2-(4-biphenyl)-5-(4-tert-butyl phenyl)-1, 3. 4-oxadiazole (PBD) which implies that PATT could be acting as better electron acceptors than widely used electron transporting material PBD.  相似文献   

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