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1.
On P? P Containing Cyclic Compounds. II. Reaction of N,N'-dimethylthiourea with phenyl dichlorophosphane yields 1.4-dimethyl-2. 3-diphenyl-1.4.2.3-diazadiphospholidine-5-thione-2-sulfide ( II ). The compound is characterized by its nmr, vibration and mass spectra as well as the results of an X-ray structural analysis. Byproduct of the reaction is N-(N,N'-dimethylcarbamimidoyl)-N,N'-dimethyl thiourea hydrochloride ( III ), which crystallizes with pyridinium chloride. Molecular and crystal structure are reported. With methyl dichlorophosphane N,N'-dimethylthiourea forms 1.2.3.4-tetramethyl-1.4.2.3-diazadiphospholidine-5-thione-2-sulfide ( IV ), which is characterized by its nmr and vibration spectra. 相似文献
2.
N.M.R. Investigation of Methylphosphonium Chloride The n.m.r. spectra of [CH3PH3]Cl in aqueous hydrochloric acid as solvent and of [OP(CH3) (OCH2CH2Cl)OCH2? ]2 in C6D6 und CD2Cl2 are described. 31P n.m.r. resonances with a line width at half height of 55 Hz are found for the H2O? HCl solutions of [CH3PH3]Cl in the solid state at 183 K. 相似文献
3.
On Trichlorophosphazo Compounds from Nitriles. III. The Reaction between Acrylonitrile and PCl3. The reaction of PCl3 with acrylonitrile at higher temperatures gives CH2Cl? CCl2? CCl2? N? PCl3 ( II ). On pyrolysis of (II), CH2Cl? CCl2? CN (IV) is form- ed. Treatment of (II) with SO, results in CHzCL? CCl2? CCl?N-P(0)Cl2 ( III ). At lower temperatures and/or in the presence of PCl3, acrylonitrile reacts with PCl3 to give the cis/ trans isomers VIa and VIb . 相似文献
4.
Diazadiphosphetidines. VIII. Further Diazadiphosphetidine Oxides and an Oxide Sulfide Synthesis and properties of 1,3-dimethyl-2-phenyl-4-diethylamino-1,3,2,4-diazadiphosphetidine-2-oxide ( II ), 1,3-dimethyl-2-diethylamino-4-phenyl-1,3,2,4-diazadiphosphetidine-2-sulfide-4-oxide ( III ), and 1,3-dimethyl-2,4-diphenyl-1,3,2,4-diazadiphosphetidine-2,4-dioxide ( V ) are reported. 相似文献
5.
Eckehard Schamberg Jürg Hoign 《Journal of polymer science. Part A, Polymer chemistry》1970,8(3):693-698
The temperature dependence of radiation-induced grafting onto poly(ethylene terephthalate), polyamides, polyacrylonitrile, and polypropylene has been investigated for several monomers. In all cases a maximum grafting yield is obtained when the reaction is performed in the temperature range of the glass transition Tg of the polymer used. This maximum yield does not only appear with radiation-induced simultaneous grafting. It also appears when the graft polymerization is induced by pre-irradiation or even by thermal decomposition of organic peroxides. It is assumed that the pronounced maximum of the reactivity at Tg is obtained because in the glassy state below Tg the radicals formed cannot react due to a reduced diffusion of the monomer, whereas above Tg the number of radicals available for polymerization will be reduced with increasing temperature. 相似文献
6.
Phosphorus pentachloride reacts with BF3 · NH3 to give [Cl3P?N? PCl3][BCl4](Va). Mechanism of formation and chemical behaviour to SO2 and H2S are described, followed by a presentation and discussion of the 31P, 19F, and 11B NMR spectra of the adducts formed by P2NOCl5 and BF3, BCl3, and PF5, respectively. 相似文献
7.
Synthesis and NMR Spectra of λ5-Diphosphets. Structure of 2,4-Diphenyl-1,1,3,3-tetrakis (diethylamino)-1λ5, 3λ5-diphosphete Preparation, properties, and n.m.r. spectra of C2H5PF2[N(C2H5)2]2, CH2?PF[N(C2H5)2]2, and the diphosphetes {RC?P[N(C2H5)2]2}2 (R) ? H ( 5a ), CH3 [( 5b )] are described. The λ5-diphosphete {HC?P(NR2)2}2 (R ? CH3) reacts with BF3 · O(C2H5)2 to give which is transformed into by n-C4H9Li. The crystal and molecular structure of 2,4-diphenyl-1,3,3-tetrakis(diethylamino)-1λ5,3λ5-diphosphete 2 are reported and discussed. 相似文献
8.
Thermolysis of Phosphorus(V) Sulfur(VI) Nitride Halides Thermolysis of compounds of the type R2PCl = N–SO2X (R = Cl, CH3, C6H5; X = F, Cl) results in the formation of the compounds R2P(O)Cl and [NS(O)X]n. Pyrolysis of the title compounds with longer chains yields, among others, the cyclic compounds III and IX. IX is also one of the decomposition products of a sulfamide derivative (XXI). Finally the thermal behaviour of carbon containing phosphorus(V) sulfur(VI) nitride chlorides has been investigated. 相似文献
9.
Yuri N. Obukhov Eckehard W. Mielke Jan Budczies Friedrich W. Hehl 《Foundations of Physics》1997,27(9):1221-1236
Thetranslation Chern-Simons type three-formcoframe∧torsion on a Riemann-Cartan spacetime is related (by differentiation) to the Nieh-Yan fourform. Following Chandia and Zanelli, two
spaces with nontrivial translational Chern-Simons forms are discussed. We then demonstrate, first within the classical Einstein-Cartan-Dirac
theory and second in the quantum heat kernel approach to the Dirac operator, how the Nieh-Yan form surfaces in both contexts,
in contrast to what has been assumed previously. 相似文献
10.
Eckehard W. Mielke 《General Relativity and Gravitation》1977,8(3):175-196
The familiar wormhole model of geometrodynamics is extended to allow for knotted embeddings of the initial hypersurface. It is shown that topology change is not only a means to modify the connectivity of the space, but also the knot invariants of its embedding. In a probabilistic framework the process of wormhole scattering can be expressed by creation and annihilation operators acting on the wave function of quantum geometrodynamics. Implications concerning Wheeler's exciton model of elementary particles, thef-gravity approach to hadronic matter, and interrelations with Jehle's flux quantization program are discussed.Work supported by a grant of the Studienstiftung des deutschen Volkes and in part by National Science Foundation grant No. GP 30799 X to Princeton University. 相似文献