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1.
Fluorination of Dioxa- and Oxazaphospholanes The fluoridolysis of cyclic esters and esteramides of phosphorous acid ( 1 , 2 , 4 , 5 , 7 , 11 , and 12 ,) using the acid fluorination reagent Et3N · nHF (n > 1) or an excess of a basic composed agent (n < 1) yields in all cases HPF5? ( 3 ,). With stoichiometric amounts of fluoride, however, the fluorophospholanes ( 4 ,) and ( 5 ,) as well as fac.- and mer.-o- ( 6a, 6b ,) and the spirocyclic fluorohydridophosphate ( 8 ,) are obtained. ( 13 ,) reacts to ( 14 ,) and the spirocyclic compound ( 15 ,) gives ( 16 ,). The fluorophosphoranes ( 18 ,), ( 19 ,), and ( 21 ,) are obtained by oxidative fluorination of the spiro- or bicyclic P? H compounds 11, 12 , and 20 , with CCl4/Et3N · nHF (n < 1). The oxidative fluorination of the cyclic triesters of phosphorous acid 7 , and 23 , leads to the cyclic fluorophosphates ( 22 ,) and 16 , as well as 6. , The compounds 18, 19 , and 22 , are also formed by oxidative fluorination of elemental phosphorus, P4, in the presence of the corresponding bifunctional nucleophile.  相似文献   

2.
Solution Thermodynamics of FeCl2 in Molten Mixtures of Alkaline Chlorides and LaCl3 or CeCl3 Activity coefficients and the chemical excess potential of FeCl2 dissolved in molten chloride mixtures were determined by EMF measurements with galvanic cells of the type in the concentration range from 0.01–5 mole-% at 720 and 820°C. An average cationic potential is defined and used to calculate a distance parameter () for the different solvent melt mixtures. may be estimated by equations of the type   相似文献   

3.
Investigations on the effects of γ irradiation on poly(methylene oxide) (POM) and poly(ethylene oxide) (PEO) have been made employing electron spin resonance (ESR) spectroscopy. The ESR sextet and doublet spectra, recorded for POM and PEO, respectively, on irradition in air at room temperature are broadened as the temperature is lowered and show a reversible change in line shape with temperature. The spectra are analyzed by computer simulation, employing Lorentzian line-shape functions and the least-squares method of total curve fitting. The component spectra are evaluated and are assigned. Superposition of the component quartet, triplet, and doublet spectra, corresponding to the radicals ?H3, ?H2O , and O?HO , respectively, together with a singlet due to the radicals ?CH2 is considered to be the best fit to the observed spectrum for POM. The doublet spectrum recorded for PEO has been assigned to the radicals ?HO . The reversible broadening of the spectra has been associated with the mechanism of molecular motions around the glass transition temperatures of these polymers.  相似文献   

4.
The electric properties of polymer composites with highly conductive 7,7,8,8-tetracyanoquinodimethan (TCNQ) salts such as quinolinium–TCNQ complex salt (), acridinium–TCNQ complex salt (), and N-methylacridinium–TCNQ complex salt () were studied. Polyacrylonitrile (PAN), poly(N-vinylcarbazole) (PVK), and poly(4-vinylpyridine), (P4VP), etc., were chosen as matrix polymers. The resistivity (ρ) of the was 0.37 Ω cm at the content of 20 wt % in the film. When the content of was increased up to 40 wt%, a phase separation of the needle crystals was observed and the ρ value increased. When was dispersed into PAN or PVK, the separation was also observed and the samples showed low conductivity. The uniform films were obtained in the and systems, but the values of ρ were high because of the degradation of the TCNQ salts. Uniform films with the naked eye were obtained in the and systems, and the values of Ω were 0.37, 1.05, and 3.40 Ω cm, respectively. was stable even when dispersed into P4VP. The properties of the composites were influenced by the combination of the TCNQ salts and the polymers. The uniformity and the stability of the composites were necessary to obtain the high conductive composites.  相似文献   

5.
On Chalcogenolates. 121. Studies on N-Cyanomonothiocarbimic Acid. 1. Synthesis and Properties of Alkali Metal N-Cyanomonothiocarbimates The hitherto unknown N-cyanomonothiocarbimates M2[SOC?N? CN] · H2O, where M = Na, K, Rb, Cs, have been prepared by reaction of the corresponding alkali metal salt of cyanamide with COS. N-Cyanomonothiocarbimates react with sulfur to form the ion, which gives with an acid and with CH3I the methyl compound . The reaction of the latter compound with H2O2 yields . All compounds have been characterized by means of diverse methods.  相似文献   

6.
Oxidative Fluorination of (CF3)(R) (R = CF3, Cl) and the Crystal Structure of (CF3)(Cl) F+ AsF6? Oxidative fluorination of (CF3)(R) (R = CF3, Cl) with XeF+MF6? (M = As, Sb) in anhydrous HF results in formation of monofluorsulfonium hexafluorometalates. The salts are characterized by vibrational, NMR, and mass spectra. (CF3)(Cl)F+ AsF6? crystallizes in the monoclinic space group P21/c with a = 9.955(10) Å, b = 11.050(5) Å, c = 12.733(15) Å, β = 97.77(5)°, and Z = 4.  相似文献   

7.
The formation enthalpies were ascertained from the solution enthalpies in 2 n NaOH resp. 2 n NaOH + 1% H2O2. The results of equilibrium measurements in the systems give the formation enthalpies and standard entropies: . The value of the standard entropy of the gaseous MoOCl4 was estimated to be 91 (±3) cl. From the enthalpies and entropies of sublimation the values were obtained.  相似文献   

8.
On Chalcogenolates. 125. Studies on N-Cyanformamidino Dithiocarbimic Acid. 1. Synthesis and Properties of N-Cyanformamidino Dithiocarbimates, Reaction with Acids and with Elemental Sulfur N-Cyanguanidine reacts with carbon disulfide in the presence of the corresponding alkali metal hydroxide to form N-cyanformamidino dithiocarbimates M2[S2C?N? C(NH2)?N? CN], where M = K and Rb. They react with acids to form and with elemental sulfur to yield . The potassium salt and the methyl compound were isolated. All compounds have been characterized by chemical and spectroscopic methods.  相似文献   

9.
On the Coordination Chemistry of Phosphines and Phosphine Oxides. XXVIII. Transition Metal Aminoalkylphosphine Complexes. Part II: Palladium and Platinum Complexes Aminoalkylphosphines – C6H5HP? CH2 · CH2? , (C6H5)2P? CH2 · CH2 · CH2? NH2, (C6H5)2P? CH2 · CH2 · CH2? N?CHC6H5 – react with palladium and platinum salts to give coordination compounds of the type MX2, MX2()2, and MX2()4 (M = Pd, Pt; X = Cl, BPh4). The chelating activity of the ligands, structure and properties of the metal complexes are discussed.  相似文献   

10.
Analysis of the 13C NMR spectra of a series of 2,3-dihydro-1H-pyrrolo[1,2-c]imidazole derivatives has provided chemical shift data for (?184 ppm), (?173.5 ppm), (?158 ppm) and (?148 ppm) groups. A full analysis of the 13C chemical shifts of the C atoms of the pyrrole ring and of an N-phenyl substituent is described.  相似文献   

11.
In this study, both monofunctional and bifunctional nucleophiles, as well as the electrophile FNO, are reacted with perfluorovinyl amines. The perfluorovinyl amines CF?CF2 and CF?CF2 have been reacted with dimethylamine and diethylamine in the presence of small amounts of water to give CHFC(O)N(CH3)2 ( 1 ), CHFC(O)N(CH3)2 ( 2 ), and CHFC(O)N(C2H5)2 ( 3 ). With perfluorovinyl pyrrolidine and perfluorovinyl morpholine, ethanolamine gives the cyclized products CHF ( 4 ) and CHF ( 5 ), respectively. Reaction of the vinyl amines with (CH3)3SiOCH2CF3 in the presence of catalytic amounts of CsF results in the formation of cis- ( 6 ) and trans- ( 7 ) CF?CF(OCH2CF3) and cis- ( 8 ) and trans- ( 9 ) CF?CF(OCH2CF3). The electrophile FNO reacts slowly with perfluorovinyl pyrrolidine and perfluorovinyl morpholine, and more rapidly with (CF3)3CCF?CF2 to give CF(NO)CF3 ( 10 ), CF(NO)CF3 ( 11 ) and (CF3)3CF(NO)CF3 ( 12 ), respectively. Single crystal X-ray analysis is used to confirm the identity of the product obtained from the controlled hydrolysis of the sultone of perfluorovinyl pyrrolidine as the sulfonic acid anhydride C(O)CF2OS(O)2OCF2C(O) ( 13 ). The X-ray crystal structure of perfluorosuccinic acid monohydrate ( 14 ), which is obtained when the perfluorovinyl pyrrolidine sultone is hydrolyzed in excess water, is also reported for the first time.  相似文献   

12.
Reduction of tribenzo[a,c,e]cyclooctene ( 2 ) and its 2,3- and 1,4-dimethyl derivatives ( 4 and 5 ), as well as of 1,1-dimethyl-10,11-propane-2,2-diylidene-1H-benzo[5,6]cycloocta[1,2,3,4-def]fluorene ( 6 ) and its 5,6-didehydro derivative ( 7 ) was followed by cyclic voltammetry. The radical anions of these compounds and those of their derivatives (D) 2 , (D) 5 , and (D) 6 , deuteratsd at C(9) in 1 and 5 or in the corresponding position of 6, have been characterized with the use of ESR, ENDOR, and TRIPLE-resonance spectroscopy. The cyclic-voltammetric and proton-hyperfine data are consistent with the increasing deviations of the radical anions from planarity in the order These deviations, due to steric or interferences in the peri-positions 1?14 and 4?5, are removed in and by the introduction of bridging groups. The non-plalarity affects the thermodynamic and kinetic stabilities of the radical anions and causes a shift in the π-spin distribution away from that benzene ring which is linked to the two others by the essential single bonds C(4a)? C(4b) and C(14a)? C(14b). This finding suggests that the steric hindrance in , and is alleviated by twisting this ring out of coplanarity with the remaining (Z)-stilbene-like π-system.  相似文献   

13.
On Chalcogenolates. 126. Studies on N-Cyanformamidino Dithiocarbimic Acid. 2. Thermal Behaviour of Potassium N-Cyanformamidino Dithiocarbimate in Solution The thermal treatment of K2[S2C?N? C(NH2)?N? CN] in methanolic solution yields . The semi-hydrate has been isolated. It reacts with acid to form The reaction with H3CI gives The compounds have been characterized by means of electron absorption, 1H- and 13C-N.M.R., infrared, and mass spectra.  相似文献   

14.
On Surface Compounds of Transition Metals. VIII. Complex Formation of a Coordinatively Unsaturated CrII Surface Compound with Nitrogen Oxides N2O forms with surface-Cr(II) a relatively unstable light blue compound of the stoichiometry 1:1, while addition of NO results in formation of a very stable dark brown, diamagnetic surface complex . By reaction with O2 this complex undergoes — depending on reaction temperature — either replacement of NO unter reoxidation of the metal (→Cr(VI)) or/and reaction of the ligand (→NO2). Direct reaction of NO2 with results in the same products as stepwise addition of NO and 1/2 O2. reacts with HCl/ROH under formation of the soluble, paramagnetic kation [Cr(NO)(ROH)n]2+, which is formulated as [Cr(II)(NO)]2+ ? [Cr(I)(NO+)]2+ accordingly to the e.s.r. spectra.  相似文献   

15.
The 1,6-methano[11]annulenyl ( 1 ·), 1,6:8, 14-propane-1,3-diylidene[15]annulenyl ( 2 ·), benzotropyl ( 3 ·) and 2,3-naphthotropyl ( 4 ·) radicals have been characterized by their ESR. spectra. The corresponding radical dianions, , , and , have also been studied both by ESR. and ENDOR. spectroscopy. Assignment of the coupling constants a to protons in the individual positions μ of these radicals and radical dianions is to a large extent based on investigations of specifically deuteriated derivatives. The radicals 1· , 2· , 3· and 4· exist in temperature-dependent equilibria with ( 1 )2, ( 2 )2, ( 3 )2 and ( 4 )2, respectively, where ( 1 )2 to ( 4 )2 denote mixtures of dimers of 1 · to 4 ·. The dissociation enthalpies, ΔH°, of ( 1 )2 (102 kJ/mol) and ( 2 )2 (88 kJ/mol) are considerably smaller than those of ( 3 )2 and ( 4 )2 which do not significantly differ from the ΔH° value of bitropyl (139 ± 6 kJ/mol). This finding indicates that the gain in π-electron delocalization energies, Δ(DE)π, upon dissociation markedly increases on going from bitropyl, ( 3 )2 and ( 4 )2 to ( 1 )2 and ( 2 )2, and thus points to an additional ‘resonance stabilization’ of 1 · and 2 ·, as compared with 3 · and 4 ·. A more pronounced π-spin localization on the 7-membered ring is observed in 3 ·, 4 ·, and relative to the corresponding species, 1 ·, 2 ·, and . It can be interpreted in terms of simple π-perimeter models without explicitly invoking substantial homoconjugative interactions between the bridged centres in 1 ·, 2 ·, and . However, the shortcomings of these crude models do not allow one to make a clear-cut statement about the contributions of the homotropyl structures to the π-systems of these paramagnetic species. The radical dianions and exhibit considerable hyperfine splittings from one 23Na or 39K nucleus of the counter-ion, whereas for and such splittings stem from two equivalent alkali metal nuclei. This finding is readily rationalized by different geometries of the bridged annulenyls and their benzo- and naphthotropyl analogues. Hyperfine data are also given for the radical anions of 7 H-benzocycloheptene, ( 3-H )\documentclass{article}\pagestyle{empty}\begin{document}$2^{\ominus \atop \dot{}}$\end{document}, and 6 H-(2,3-naphtho)cycloheptene, ( 4-H )\documentclass{article}\pagestyle{empty}\begin{document}$2^{\ominus \atop \dot{}}$\end{document}, as well as for the radical dianion of 1,6:8,14-bismethano[15]annulenyl, 5 \documentclass{article}\pagestyle{empty}\begin{document}$2^{\ominus \atop \dot{}}$\end{document}.  相似文献   

16.
Influence of Ring Size and Substitution on the Oxidative Addition of Cyclic Carboxylic Acid Anhydrides and Imides to the Moiety (N N)Niº (N N = bipy, tetramethylethylenediamine) (dipy)(COD) or a mixture of tmed/Ni(COD)2 easily react with cyclic carboxylic acid anhydrides by an oxidative addition. After decarbonylation with succinic acid anhydride a five-membered, with glutaric acid anhydride a six-membered metallacycle are formed – or With diphenic acid anhydride we obtained a seven-membered chelate in the boat form ( XIV ). Along their bond axis the two aromatic rings are twisted by 127°, i.e. the conjugative interaction is weak. Itaconic acid anhydride, as a polar olefine, can coordinate to the moiety (tmed)Ni side-on. But also on oxidative addition, yielding the five-membered chelate ( XVI ), is possible. The five-membered chelate is the only Product of the reaction with (dipy)Ni(COD). 1.8-naphthalic acid anhydride (NSA), because of its rigidity, is not suitable for an oxidative addition to electron-rich nickel(O) complexes. But as a π acceptor ligand with a relatively low half wave potential NSA displaces COD of (dipy)Ni(COD) forming (dipy)Ni(NSA) · 0.25 THF ( XVIII ). One of the final products of the acidolysis of [(dipy)Ni]2(PPI) · 1.5 THF ( XIX PPI=N-phenyl phthalimide) is benzanilide, a compound which might be an indicator of an oxidative additive connected with an -bond breaking in the course of the synthesis of XIX . But ir-data shows the framework of PPI to be preserved in the complex XIX . Evidently the bond breaking proceeds in the course of the acidolysis.  相似文献   

17.
On Chalcogenolates. 153. Studies on Derivatives of N-Thioformyl Dithiocarbamic Acid. 3. Esters of N-Thioformyl Dithiocarbamic Acid and Oxidation of N-Thioformyl Dithiocarbamates The esters of N-thioformyl dithiocarbamic acid have been prepared by reaction of tetra-n-butylammonium N-thioformyl dithiocarbamate with the corresponding alkyl iodide. Also the reaction of S-methyl N-formyl dithiocarbamate with Lawesson reagent forms the methyl ester of N-thioformyl dithiocarbamic acid. The oxidation of N-thioformyl dithiocarbamates with iodine yields 1,2,4-dithiazole-3-thione All compounds have been characterized by means of chemical and diverse spectroscopic methods. A new method to prepare 5-phenyl 1,2,4-dithiazole-3-thione is given.  相似文献   

18.
The photoelectron spectra of the four oxygen and nitrogen analogs of thiathiophthene 1 to 4 are reported and discussed. The first two bands are assigned to ionization from the π- and n-molecular orbitals on the basis of CNDO/2 calculations. The assignment of bands and to ionization from π-molecular orbitals is suggested.  相似文献   

19.
The photoelectron (PE.) spectrum of the title compound has been assigned by comparison with the PE. spectrum of cubane ( 2 ), aided by ab initio STO-3G calculations using localized molecular orbitals. On the basis of the information available to date, the most satisfactory orbital sequence, Koopmans theorem implied, is, in descending order of energy: band system : (2e″2, 3e′2 2e″1, 3e′1); band system : 3a′1 (2e′2, 2a″2); band : 2e′1.(Sequence of orbitals in parenthesis uncertain).  相似文献   

20.
Fast atom bombardment (FAB) mass Spectrometry of the two hydrido carbene compounds trans-[(PPh3)2HPt(carbene)]BF4 (carbene = and was studied. Some retrosynthetic processes are involved in the fragmentation pathways. The reactions with NaCI were also studied under FAB conditions and the results were compared with those obtained in solution.  相似文献   

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