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111.
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113.
Addition and Substitution Reactions at Tetrafluoro- and Tetrachlorodiborane(4) From equimolar mixtures of B2F4 and MenN(SiMe3)3-n (n = 0–3) the mono-addition products 1–4 are formed at low temperatures. By elimination of Me3SiF the adduct 2 gives the dimeric monosubstituted diborane 8 , which slowly decomposes at room temperature to the aminoborane 6 and (BF)n. The course of the reactions was studied by means of 11B and 19F NMR spectroscopy and by measuring the vapor pressures. According to the 11B and 31P NMR spectra the reaction of B2Cl4 with PCl5 or [Me4N]Cl in liquid hydrogen chloride at 0°C does not yield [PCl4]2+[B2Cl6]2? or [Me4N]2+[B2Cl6]2? but gives [PCl4]+[BCl4]?, PCl3 and BCl3 or [Me4N]+[BCl4]? and BCl3 besides (BCl)n. 相似文献
114.
The Molecule S?GeCl2. Matrix IR Investigation and Ab initio SCF Calculation Molecular S?GeCl2 is found in a matrix reaction between the high-temperature molecule Ge?S and Cl2. A structure analog to that of phosgene can be derived from the isotopical shifts (70Ge/72Ge/73Ge/74Ge/76Ge and 35Cl/37Cl) within the IR spectra. The normal coordinate analysis results for the Ge?S force constant a value of 4.21 mdyn/Å. The spectroscopic results are confirmed by ab initio SCF calculations. 相似文献
115.
2,2-Difluoro-1,2,3-trimethyl-1,3-diaza-2λ5-phospholidine The title compound 1 is obtained in about 50% yield by oxidative fluorination of 1,2,3-trimethyl-1,3-diaza-2λ3-phospholidine, 6 , with IF5. 1 is characterized by its nmr, mass, and ir spectra. 相似文献
116.
Organometallic Lewis Acids. XLII. Carbonyl- and Nitrosyl Complexes of Manganese and Rhenium of Weakly Coordinated Anions (Ph3P)2(ON)2MnX, (Ph3P)n(OC)5–nMX (M = Mn, Re; n = 1, 2; X = FBF3, OSO2CF3, OSO2F, OCORf) The complexes (Ph3P)2(ON)2MnX (X = FBF3, OSO2CF3, OSO2F, OCOCF3, OCOC3F7) and (Ph3P)n(OC)5–nMX (M = Mn, Re; n = 1, 2; X = FBF3, OSO2CF3) have been obtained by reaction of (Ph3P)2(ON)2MnH and (Ph3P)n(OC)5–nMeMe with the corresponding acids HX or from (Ph3P)n(OC)5–nReBr (n = 1, 2) with silver salts AgX, respectively. The compounds have been characterized by their IR and partially by 19F-NMR data. An efficient method for the preparation of the hydride (Ph3P)2(ON)2MnH is reported. 相似文献
117.
Ammonium Chloro(thio)phosphate Betaines, a Class of Coordination-stabilized Chloro(thio)metaphosphates Ammonium chloro(thio)phosphate betaines behave like systems being in equilibrium with tert. amine and monomeric chloro(thio)metaphosphate. In solution at room temperature the amine component can be displaced by stronger donors. Mass spectra reveal the presence of ClPS2 as monomer and dimer, of ClPO2 by fragment ions of the dimer, trimer, and tetramer before reorganization takes place to form PXCl3 and P4X10 (X = O, S). Detection of ClPOS fails owing to fast equilibration into ClPO2 and ClPS2. 相似文献
118.
新型含有机硅二元多嵌段共聚物的研究 总被引:1,自引:0,他引:1
报道了聚羟基醚(PHE)、聚羟基醚砜(PHES)、酚酞聚羟基醚(PPHE)和聚对羟基苯乙烯(PHS)与端胺基聚二甲基硅氧烷(PDMS)通过羟胺缩合生成ABmn新型结构的可溶性含有机硅二元多嵌段共聚物,m值在1~6之间,详细讨论了反应物浓度对共缩聚反应的影响,并通过分子量测定、红外光谱分析和动态力学分析(DMA)技术初步确定了其反应机理、结构和动态力学性能. 相似文献
119.
A polyphosphide of the type (NaP)X 1 was obtained from red phosphorus and sodium in presence of small amounts of naphthalene in 1,2-dimethoxyethane as solvent. 1 reacts with alkyl halides in dependence on the kind of alkyl group with formation of different alkylcyclophosphanes. As definite compounds Me5P5 2 , Et5P5 3 (with not definite constitution), i-Pr4P4 4 and t-Bu4P4 5 could be isolated. 1 was identified by X-ray diffraction, 2 – 5 by means of their 1H, 13C, 31P n.m.r. and mass spectra. The molecular structure of 4 was identified by electron diffraction. 相似文献
120.
Monir Uddin Antonis G. Hatzidimitriou Maria Lalia-Kantouri Chris Tsiamis 《Structural chemistry》1997,8(2):131-139
The infrared and electronic excitation spectra of a series of new nickel(II) chelates containing an-diimine (or nitrogenous base, enR) and the anion of a-dione (1,3-ketoenol or 1,3-ketoester,H) were obtained in the solid state and in solution. The composition and the overall structure of the new chelates in the solid state depends on ligand concentration, the substituents within the-dionato moiety and the counterion present. The IR and electronic excitation spectra of [Ni(enR)2
]NO3 and [Ni(enR)(O2NO)] indicate, in conjunction with other physicochemical measurements, bidentate coordination of the ligands, while the spectral shifts reveal replacement of the (O,O)nitrato group by basic solvents. The existence of the nickel(II) in an octahedral environment is confirmed by an X-ray structure analysis of [Ni(dpamH)2acac]NO3 · CH3OH (monoclinic, space groupP2l/n, a=17.296(1),b=7.462(1),c=21.604(3) å,=95.65(1),Z=4, R=0.0534,Rw=0.0600), where dpamH denotes the 2,2-dipyridylamine. 相似文献