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Polymeric cyanodithioformic acid has been prepared by interaction between a solution of Na[NCCS2]. 3 DMF and HCl(aq). In the gaseous state there exists [NCCS(SH)]x with x = 1 and 2. The instable crystalline acidodithioformic acid is formed on reaction of Na[N3CS2] with HCl(aq). In the gaseous state there exists the monomeric acid N3CS(SH).  相似文献   

3.
On Chalcogenolates. 133. Studies on Esters of Haloformic Acids. 1. Alkyl Esters of Chloroformic, Chloromonothioformic, and Chlorodithioformic Acids The prepared esters RO? CO? Cl, RS? CO? Cl, RO? CS? Cl, and RS? CS? Cl with R = alkyl have been characterized by means of electron absorption, infrared, nuclear magnetic resonance, and mass spectra.  相似文献   

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On Chalcogenolates. 81. Studies on N-Hydroxy Dithiocarbamic Acid. 3- Esters of N-Hydroxy Dithiocarbimic Acid and Dithiocarbamic Acid The reaction between hydroxylamine, carbon disulfide, and alkyl halide leads to the corresponding ester of N-hydroxy dithiocarbimic acid HO? N?C(SR)2 with R = CH3, C2H5; R2 = ? CH2? CH2? . The phenyl ester of N-hydroxy dithiocarbamic acid HO? NH? CS(SC6H5) has been prepared by reaction of hydroxylammonium chloride with the phenyl ester of chlorodithioformic acid. N-Methyl hydroxylammonium chloride reacts with carbon disulfide and alkyl iodide to form the corresponding ester of the dithiocarbamic acid HO? N(CH3)? CS(SR) with R = CH3, C2H5. The unstable compounds have been characterized by different methods.  相似文献   

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UV.-irradiation (λ = 254 nm) of the hydroxy-enones 3 and 6 in acetonitrile results in the cyclization to the unstable isomeric allylic alcohols 4 and 7 , which dehydrate easily to the isolated unsaturated ether 5 and 8 . The racemic γ,δ-dihydroxy-enone 9 upon irradiation under the same conditions gives rise to the exclusive formation of the furane-compound 11 .  相似文献   

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On the viscosity of molten salts. II. The viscosity of molten aluminium halides The datas of viscosity of molten aluminium chloride, bromide, and iodide determined by means of the hollow-body torsion method are described and discussed in connexion with the equations of ANDRADE and BATSCHINSKI. The datas for the bromide and iodide are in good agreement with the experience and the theory of molecular melts. The aluminium chloride shows deviations in several facts.  相似文献   

10.
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   

11.
Aminomethylation of Phosphoro-, Phosphono-, Phosphinoamidoates and -amidothioates Dialkylphosphoroamidates, alkyl-phosphonoamidates and phosphonoamidothioates react with C2H5O? CH2? NR2 and HCOH/HNR2, respectively, as like as a N-aminomethylation forming the corresponding derivatives of the general formula R2P(X)? NR′? CH2? NR″2? R = alkoxy, alkyl, aryl; R′ = H, alkyl; X = O, S; R″ = alkyl, cycloalkyl —. Under the same conditions phosphonodiamidoates and phosphonodiamidothioates yield RP(X)-[NR′? CH2? NR″2]2 or RP(X)? NHR′? (NR′? CH2? NR″2) only. These compounds are not formed by interactions of RP(X)(NR′? CH2OH)2 with sec. amines. The aminomethylation of (C6H5)2P(S)NH2 gives unexceptional [(C6H5)2P(S)]2N? CH2? NR′2. The i.r. and 1H-n.m.r. data of the prepared compounds, which can't be distilled mostly, are discussed.  相似文献   

12.
Preparation for erythro-2-Hydroxy-succinic Acid Derivatives from Malic Esters As a contribution to the much discussed diastereoselective synthesis of enantiomers of open chain compounds, > 90% erythro-selective branching of malic esters by alkylation of the doubly deprotonated derivative 2 (alkoxide-enolate) with methyl, allyl, and benzyl halides in THF at ?78° (→ 3aa, 3ba, 3bb, 3bc , Table 1) is described. A second alkylation (→ 4 ) and addition of 2 to acetone (→ 5 ) are also possible. Cyclization of 2 to the enantiomerically pure trans-epoxides 6 is achieved by treatment with iodine. Cuprate opening of 6b furnishes the same product 3ba obtained from the methylation of 2b , establishing the configurational assignment.  相似文献   

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On Chalcogenolates. 111. Studies on Perthiocyanic Acid. 4. Crystal and Molecular Structure of Dimethyl Perthiocyanate (CH3)2C2N2S3 crystallizes with Z = 4 in the monoclinic space group P21/c with cell dimensions a = 7.661(4) Å, b = 11.675(5) Å, c = 9.549(5) Å, β = 116.7(3)·. The crystal and molecular structure has been determined from single X-ray data at 20°C and refined to a conventional R of 0.062. The structure consists of isolated 3,5-bis(methylmercapto)-1,2,4-thiadiazole molecules. The 1,2,4-thiadiazole ring is plane and stabilized by mesomerism.  相似文献   

15.
Using an adiabatic calorimeter, the heat of transition Sα ? Sβ, the heat of fusion of Sβ and the specific heat of the liquid had been determined on sulfur samples refined by zone melting and samples doped with chlorine, bromine and iodine. The data obtained from pure sulfur (heat of fusion: 1608 ± 8 J/Tom, specific heat of the liquid at 120°C: 29,4 J/Tom.°C) are about 10% lower than comparable values of other authors. Apparently they represent heat of fusion and specific heat of the pure cyclooctasulfur. The measurements on doped samples (δHS = 1736 ± 10 J/Tom) are in agreement with the data reported in literature and include a portion of enthalpy from the transition reaction of cycloocta-sulfur (Sλ) to catenaocta-sulfur (Sπ), requiring extremly long equilibrium times in pure sulfur. The influence of impurity on the caloric properties of the liquid sulfur is also indicated by the increasing width and decreasing highness of the Cp-maximum at 159°C with increasing amount of halogens. For the heat of transition Sα → Sβ, independent of the amount of impurity, the literature data could be confirmed. At the samples doped with iodine there was observed a previously unreported transition near 65,9°C.  相似文献   

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On Chalkogenolates. LXIV. Studies on Thioformic Acids. 7. Crystal Structure of Tetraethylammonium Cyanidithioformate Tetraethylammonium cyandithioformate [(C2H5)4N][NCCS2] crystallizes in the orthorhombic space group Pbem? D (no. 57): a = 7.715; b = 13.945; c = 12.255 Å and Z = 4. Planar cyandithioformate ions are packed parallel the xy plane at z = 0.25 and 0.75. The nitrogen atoms of the ammonium groups build columns along the glide plane c. Structural refinements were completed to a weighted R = 0.078.  相似文献   

18.
The essential characteristics of a simple, discontinuous model system for mass transfer between two phases are discussed. It is shown that for dyeing processes that conform to this model it is possible, with the aid of the methods of non-equilibrium thermodynamics, to give an unambiguous definition of the concepts «rate of dyeing» and «affinity of dyeing», at any stage of dyeing. It is clear from the derived phenomenological equations that dyeing systems rarely reach a true equilibrium state (i.e. a stationary state of zero order), but that in general an osmotic or a DONNAN equilibrium is attained.  相似文献   

19.
On Chalcogenolates. 122. Studies on N-Cyanomonothiocarbimic Acid. 2. Potassium S-Methyl N-Cyanomonothiocarbimate and S-Methyl N-Cyanomonothiocarbimic Acid The reaction of K2[SOC?N? CN] · H2O with H3CI gives K[O(H3CS)C?N? CN]. The potassium salt reacts with acid to form (HO)(H3CS)C?N? CN and with H3CO? CO? Cl to yield (H3CO? CO? O)(H3CS)C?N? CN. The compounds have been characterized by means of spectroscopic methods.  相似文献   

20.
Crystal Structures of Acid Hydrates and Oxonium Salts. VIII. Dihydrate and Primary Ammonium Salt of Trimetaphosphimic Acid The dihydrate of the crystal structure of trimetaphosphimic acid, H3(PO2NH)3 · 2H2O, crystallizes in the monoclinic space group P21/c with four formula units in the unit cell (a = 7.022(1), b = 14.008(1), c = 9.353(2) Å, β = 93.34(2)°). The primary ammonium salt includes one molecule of methanol in its crystal structure, the orthorhombic space group Pbca contains eight formula units NH4H2(PO2NH)3 · CH3OH in the unit cell (a = 15.025(3), b = 7.264(1), c = 19.252(1) Å). The crystal structures have been determined from three-dimensional X-ray diffraction data collected with an automatic single crystal diffractometer. Both rings of phosphorus and nitrogen atoms show boat conformation with the nitrogen atoms in the imido form. A similar pattern of bond lengths in both molecules and the disorder of one water-oxygen atom in the dihydrate indicate a partial proton transfer from the acid molecule to the water structure. In both structures the anion is linked to other anions by three hydrogen bonds N–H ?O, with an approximate length of 2.9 Å and two very short hydrogen bonds O–H ?O of approximate length 2.5 Å.  相似文献   

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