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71.
10‐Propylthio‐5,10‐dihydrophenarsazine 2 was obtained by the reaction of 10‐chloro‐5,10‐dihydrophenarsazine 1 with propanethiol in the presence of triethylamine under mild conditions. The structure of 2 was established by X‐ray single crystal diffraction. The reaction of 2 with 2,4‐bis(ethylthio)‐1,3,2,4‐dithiadiphosphetane‐2,4‐disulfide 3 at room temperature affords a novel route to S‐10(5,10‐dihydrophenarsazine) S′‐ethyl‐S″‐propyltetrathiophosphate 4 . © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:287–291, 2000  相似文献   
72.
Interaction of sound impulse with porous layer is investigated. The presence of a barrier shielded by the layer and the gap between the porous layer and the barrier is possible. Method of calculation in linear approximation of pressures and tensions in the porous layer, gap, and on the barrier has been proposed. The method serves to interpret data on acoustic waves interaction with porous layer obtained experimentally or with the use of finite-difference methods. Specifics of acoustic wave propagation into the porous layer and further reflection from the barrier has been studied. Comparison of calculation data with experimental data of other authors on impulse propagation through the porous plate submerged in water has been carried out.  相似文献   
73.
The condensation of 4-hydroxy-3,5-diphenyl-2-phenyliminothiazolidine with 4,5-dimethyl-1,2-phenylenediamine affords 7,8-dimethyl-3-phenyl-1-phenyliminothiazolo[3,4-a]quinox-alin-4(5 H)- one; the condensation with 1,2-phenylenediamines containing different substituents at positions 4 and 5 gives both theoretically possible isomeric thiazolo[3,4-a]quinoxalines, which differ in the distribution of these substituents between positions 7 and 8 in the benzene ring of the quinoxaline system. 3a-Hydroxy-7,8-dimethyl-3-phenyl-l-phenylimino-3,3a-di-hydrothiazolo[3,4-a]quinoxalin4(5 H)- one was isolated and characterized as the intermediate of the reaction giving rise to thiazolo[3,4-a]quinoxaline from 4,5-dimethyl-1,2-phenylene-diamine. This intermediate is a covalent hydrate of the final product.  相似文献   
74.
Reactions of 1,3-dipolar cycloaddition of bis(2-chloroethyl)-2-nitroethenylphosphonate to methyl and ethyl diazoacetates proceed with the formation of a mixture of regioisomers of phosphorylated nitropyrazoline carboxylates that under the reaction conditions undergo isomeric transformations and denitration and afford a mixture of Δ1- and Δ2-pyrazoline- and pyrazolecarboxylates. Structures of the synthesized substances are studied by the methods of IR and 1H, 31P NMR spectroscopy and partially by X-ray structural analysis.  相似文献   
75.
76.
Reactions of 4,6-dinitro-5,7-dichlorobenzofuroxane with substituted pyrimidines in aqueous DMSO proceed through an intermediate formation of 5-hydroxy-4,6-dinitro-7-chlorobenzofuroxane owing to the hydrolysis of one of the chlorine atoms with the subsequent formation of pyrimidine salts exhibiting a high biologic action.  相似文献   
77.
Pentaphenyl- and penta-p-tolylantimony were reacted with benzophenone oxime or triarylantimony bis(benzophenonoximate) in toluene to obtain tetraarylantimony benzophenonoximate. Triarylantimony bis(benzophenonoximates) were prepared by oxidative addition from tryarylstibine and oxime in ether in the presence of hydrogen peroxide. X-ray diffraction analysis of tetraphenylantimony benzophenonoximate was performed to show that coordination of the antimony atom is trigonal-bipyramidal and the oxime oxygen atom is axial.  相似文献   
78.
Chloromethylphosphonic dichloride reacts with o-aminophenol in the presence of triethylamine to form 2-chloromethyl-1,3,2-benzoxazaphospholine 2-oxide and 2-chloromethyl-2,2'-spirodi[1,3,2-benzoxazaphospholine] in a 1 : 1 ratio. 3-Diethylaminomethyl-2-ethoxy-1,3,2-benzoxazaphospholine reacts with o-aminophenol to form 2-diethylaminomethyl-2,2'-spirodi[benzo-1,3,2-oxazaphospholine]. The crystal and molecular structures of the synthesized spirophosphoranes were determined by single crystal X-ray diffraction.  相似文献   
79.
Journal of Solid State Electrochemistry - Efficient two-step electrosynthesis of xCoO–yCo(OH)2 (CoOxHy)-supported silver nanoparticles (AgNPs) is carried out in N,N-dimethylformamide (DMF)...  相似文献   
80.
The method of molecular layering is used to prepare CdS thin films and CdS/ZnS and CdS/CdSe superlattices. The dependence of the exciton photoluminescence on film thickness is studied, and the role of internal strains is examined. The effect of the excitation intensity on the superlattice photoluminescence spectra is examined, manifested in a shift of the emission maximum toward shorter wavelengths when this intensity is increased. Fiz. Tverd. Tela (St. Petersburg) 40, 820–821 (May 1998)  相似文献   
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