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1.
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   

2.
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   

3.
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   

4.
Adsorption of various acids on anatase of high surface area was studied. Phosphoric, arsenic, sulphuric and acetic acid are specifically adsorbed; hydrochloric and perchloric acid are not adsorbed. Phosphate ions are bound on the TiO2 surface also from NaH2PO4 and Na2HPO4 solutions; sodium ions are adsorbed at the same time. OH? ions on the surface are replaced by anions such as H2PO in these reactions. The bonding of adsorbed phosphate ions is not purely ionic. Infrared spectra show that adsorbed acetic acid is bound as acetate. NO2 reacts with the basic OH? ions undergoing disproportionation; OH? ions are replaced by NO ions. Phophoric acid adsorption corresponded always to half the total OH population on five different TiO2 samples. The TiO2 surface is not completely covered by OH groups. The maximum coverage is ca. 7.5 μMol OH/m2.  相似文献   

5.
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   

6.
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   

7.
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   

8.
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   

9.
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   

10.
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   

11.
On Ordered Perovskites with Cationic Vacancies. XI. Compounds of Type A B B □1/4WVIO6 ? A BIIB □W O24 with AII, BII = Ba, Sr Depending on the ionic radii of the two and three valent cations in the perovskites of type ABB □1/4WVIO6 ?; ABIIB □WO24 order disorder phenomena are present. The results of the x-ray and vibrational spectroscopic investigations as well as the diffuse reflectance spectra and the visible photoluminescence are reported.  相似文献   

12.
On the Formation of Polysulphane Diphosphonates by the Reaction of Monothiophosphonate with Disulphane Diphosphonate In acid solution SPO reacts with S2P2O forming higher polysulphane diphosphonates. The formation of S3P2O and S4P2O is proved by evaluation of the double labelling with 35S? 32P after high paper electrophoresis.  相似文献   

13.
Some tetracoordinated complexes having the formulae, [AgL4]X (L = Triphenyl-arsine; X = NO, ClO and BrO) and [AgL3X] (L = Triphenyl-arsine/phosphine; X = SCN? and NCO?) have been prepared and characterised by analyses, conductance, magnetic susceptibility and infra-red spectroscopy.  相似文献   

14.
Kordes and Nolte are of the opinion that, on melting, Na2W2O7 dissociates according to the reaction whereas Gelsing et al. assume a dissociation into Na+ ions and a mixture of chains of WO4 tetrahedra (WO, W2O, W3O, etc.). In the present paper it is demonstrated that a dissociation according to the ideas of Gelsing et al. can excellently explain the cryometric results found by Kordes and Nolte themselves. The dissociation scheme proposed by Gelsing et al., is even more likely than that proposed by Kordes and Nolte when the results of surface tension measurements reported by Gossink and Stevels are taken into account.  相似文献   

15.
On the Formation of Monoselenane and Monotellurane Disulphane-diphosphonate by the Reaction of SPO with Seleno and Telluropolythionates In the reaction of seleno- and telluropolythionates with SPO, SeS2P2O and TeS2P2O are formed and are described for the first time. Polysulfphane-diphosphonates, -disulphonates and -phosphonsulphonates occur as side and consecutive products. By evaluation of radiochemical double labelling with the nuclide pairs 35S? 32P and 35S? 75Se, it is possible to identify the products formed and obtain information about the reaction mechanism.  相似文献   

16.
30 new binary salts of the heretofore unknown type [Co(NioxH)2(Amin)2]X were obtained by air oxidation of an alcoholic aqueous solution of CoII acetate in the presence of 1,2-cyclohexanedione dioxime (nioxime) and an aromatic amine (aniline, o-and p-ethylaniline and m-xylidine). From the brown solutions of the resulting; Co(NioxH)2(amine)2; acetates the desired salts were separated by means of double decomposition reactions using X ? Br?, NO, ClO, HSO, Pikart, [Cr(NH3)2(NCS)4]?, 1/3[Cr(NCS)6]3? and [Co(NioxH)2(NO2)2]?; NioxH ? C6H9N2O2. From spectroscopical investigations in the UV and IR regions some structural problems are resolved and discussed.  相似文献   

17.
On Perovskites A B B WVIO6 Compounds of type ABBWVIO6 can be obtained with AII ? Ba; BI ? Li, Na and BIII ? La, Nd, Sm, Gd, Y, In, Sc just as with AII ? Sr, BI ? Li and BIII ? La, Nd, Sm, Gd, Y, In (all cubic ordered perovskites). For the cubic perovskites Sr2Na0,5La0,5WO6 and Sr2Na0,5Nd0,5WO6 additional superlattice reflections are observed (a ∽ 16.4 Å). The compounds Sr2Na0,5BWO6 crystallize with BIII ? Sm, Gd in a monoclinic and with BIII ? Y, In in a rhombic distorted perovskite lattice. For the perovskites with A = Sr — dependent on ionic radii of the B ions — two different lattice types are present.  相似文献   

18.
Studies on the Reactivity of Isomeric Heterodinuclear Fischer-Carbene Complexes exhibiting a Titanaoxetan or Titanaoxolen Substructure – Cycloreversion and Insertion Reactions The reactivity of isomeric four- and five-membered carbene complexes Cp*2 3 and Cp*2 4 [MLn: Cr(CO)5 ( a ); W(CO)5 ( b ); Cp*: C5(CH3)5] has been investigated. A cycloreversion reaction, unusual for common metallaoxetanes, is found to dominate the chemical behaviour of 3 . The generation of vinylidene fragment [Cp*2Ti?C?CH2] 2 as an intermediate is proved either by trapping with ethylene and isocyanate or by protonation of the α-carbon atom. On the other hand no cycloreversion is observed for the titanaoxolene carbene complexes 4 . Ringenlargement is found by the reaction of 3 and 4 with isonitriles under formation of iminoacyl complexes. Accordingly 2,6-dimethylphenylisonitrile reacts with 3 b forming Cp*2 12 [Ar: 2,6-(CH3)2? C6H3]. A reversible insertion of cyclohexylisonitrile in 4a leads to isolation of the six-membered metallacycle Cp*2 16 (Cy: C6H11).  相似文献   

19.
Silaheterocycles. III. Synthesis and Reactivity of Di-tbutylneopentylsilaethene, Bu Si?CHCH2But The three di-tbutylvinylsilanes BuSi(X)CH?CH2 (X = H 5 , X = F 9 , X = Cl 22 ) are prepared by the reaction of their SiCl precursors with vinyl lithium. In the treatment with LiBut the first step is the generation of the α-lithio compound BuSi(X)CH(Li)CH2But, the following reactions are governed by the nature of the substituent X and the reaction conditions (solvent, concentration, temperature). For X = H 2,3-LiH elimination leads to BuSi(H)CH?CHBut ( 7 ), with X = F or Cl Si?C formation by 1,2-LiX elimination competes with intermolecular Si-C-coupling producing BuSi(H)CH(SiBuCH?CHBut)CH2But ( 13 ) as the main product. BuSi?CHCH2But ( 1 ) probably coordinates to LiBut and reacts to yield BuSiCH?CHBut ( 3 ) and 7 , forms tetrabutyl-dineopentyl-1,3-disilacyclobutane 2 by cyclodimerization and 13 by addition of BuSi(X)CH(Li)CH2But.  相似文献   

20.
The Chemistry of Metal Carbonyls and Cyano Complexes in Liquid Ammonia. XXXI. On the Reactions of Cationic η5-Cyclopentadienyl-molybdenumcarbonyl Complexes with Liquid Ammonia Depending on the reaction conditions, the cationic complexes [η5-C5H5Mo(CO)3L]+ (L = NH3, PPh3, CO) react with liquid ammonia according to: The characteristics and reactivities of the new carbomoyl derivatives are described.  相似文献   

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