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991.
Elwira Chrobak Andrzej Maślankiewicz Magdalena Chyćko Leszek Skrzypek Małgorzata Szmielew Maria J. Maślankiewicz 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):1208-1225
Abstract Treatment of 1,4-dithiino[2,3-c:5,6-c′]diquinoline (a thioquinanthrene) (1a) with an excess of nitrating mixture (0 °C, 14 days) led to a mixture of mono- and dinitrothioquinanthrene 7-oxides 2b–e and 2f–h. This mixture was: (i) reduced to a mixture of mono- and dinitrothioquinanthrenes 1b– e, or (ii) oxidatively chlorinated with a gaseous chlorine/80% acetic acid/hydrochloric acid system to a mixture of 4-chloro-3-chlorosulfonylquinoline 3a and its 5- and 8-nitroderivatives 3b and 3d. Sulfochlorides 3a– d were independently synthesized from 3,4′-diquinolinyl sulfides 4 and converted to the respective 4-dimethylamino-3-quinoline-N,N-dimethylsulfonamides 9a–d. 相似文献
992.
Roman Mazurkiewicz Beata Fryczkowska Rafał Gabański Roman Luboradzki Andrzej Włochowicz Wojciech Mól 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2589-2598
A reaction of g -carbonyl phosphorus ylides with imidoyl halides gives hitherto unknown g -( N -acylamino)vinylphosphonium salts. The same product can be obtained using the N-monosubtituted amide/Ph 3 PBr 2 /Et 3 N system instead of imidoyl halide. The key step of the reaction probably involves an intramolecular [1,3] O-to-N migration of the vinyl group, converting the primary O -imidoylation product into g -( N -acylamino)vinylphosphonium salt. 相似文献
993.
Jürgen Voss Abraam Sarafidis Andrzej Sawluk Gunther Schmidt Gunadi Adiwidjaja 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2249-2276
Novel arene-bis- and -tris(α-oxoethanedithioate) esters of the benzene, the biphenyl, and, in particular, the naphthalene series were prepared by reaction of the corresponding diazoacetyl or bromoacetyl derivatives with elemental sulfur in the presence of triethylamine in dry DMF, and subsequent direct alkylation of the produced dithiocarboxylate anions. The thiolation reaction of the diazoketones was significantly promoted by the addition of anhydrous calcium chloride (calcium chloride–activated thiolation, or CAT). Certain carbonyl-activated methylene and methyl compounds exhibiting no bromo or diazo substituents could be also transformed into dithioesters by the CAT reaction. The structure of three dithioesters was corroborated by X-ray structural analyses. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
994.
Jan Michalski Andrzej Łopusinski Lech Łuczak 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):115-118
Abstract Phosphoranesulphenyl halides of the general formula RR'P(Y)SX and their selenium analogues RR'P(Y)SeX (X=Cl,Br; Y=O,S) have been shown to be useful intermediates for access to many new classes of compounds con-taining phosphorus, sulphur, or selenium centers.' 相似文献
995.
996.
Stefan Zawadzki Andrzej Wijata 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):307-311
Abstract The convenient synthesis of N-phosphorylated formamidines, 3 based on the reaction c diethyl(ethoxymethylene)phosphoramidate, 1 with primary and secondary amines is described. 相似文献
997.
Wojciech Dabkowski Andrzej Łopusiński Jan Michalski Czesłw Radziejewski 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):375-377
Abstract Racemic and optically active S-sulphonylphosphinothioates R-SO2-S-P(O)Bu'Ph and dithioates R-SO2-S-P(S)Bu'Ph (R [dbnd] Me, p-tolyl) have been prepared for the first time by the reaction of the corresponding acids Bu'PhP(S)SH (X [dbnd] O,S) of their salts with sulphonylating reagents RSO2-Y (Y [dbnd] Cl, O-SO2R, triazolide). 相似文献
998.
Andrzej Eilmes 《International journal of quantum chemistry》2014,114(4):261-270
Effect of molecular vibrations on the absorption spectra simulated via a sequential approach combining molecular dynamics (MD) with quantum‐chemical calculations has been investigated. Simulated spectra have been obtained from the time‐dependent density functional theory results averaged over series of molecular geometries retrieved from Born–Oppenheimer MD trajectories. Distributions of bond lengths have been analyzed and related to the features of calculated spectra. For NVE simulations of small systems, absorption spectra exhibit bimodal bandshape as a result of classical treatment of vibrations. For NVE trajectories of larger systems or simulations in the NVT ensemble calculated absorption bands are symmetric, however, they may not agree with the results of Franck–Condon analysis. These results are practical manifestations of effects predicted theoretically from general principles. Consequences for the modeling of absorption spectra have been discussed. © 2013 Wiley Periodicals, Inc. 相似文献
999.
The synthesis of diethyl [2-(2-alkyl-3-oxo-2,3-dihydro-1H-isoindol-1-yl)ethyl]phosphonates and diethyl [3-(2-alkyl-3-oxo-2,3-dihydro-1H-isoindol-1-yl)propyl]phosphonates, via metallation (sec-BuLi) of N-substituted isoindolin-1-ones and then the reaction of the generated lithiated species 4 with diethyl vinylphosphonate or diethyl 3-bromopropylphosphonate, respectively, is described. 相似文献
1000.
Marcin Stec Adam Tatarczuk Dariusz Śpiewak Andrzej Wilk 《Journal of solution chemistry》2014,43(5):959-971
The densities of aqueous mixtures of aminoethylethanolamine (CAS #000111-41-1) were measured over the entire compositional range at temperatures of 283.15–343.15 K. The results of these measurements were used to calculate excess molar volumes and isobaric thermal expansion coefficients, and partial molar and apparent molar volumes and excess isobaric thermal expansion coefficients were subsequently derived. The excess molar volumes were correlated as a function of the mole fraction using the Redlich–Kister equation. Temperature dependences of the Redlich–Kister coefficients are also presented. The partial molar volumes at infinite dilution of AEEA in water were determined using two different methods. In addition, the solution density was correlated using a Joubian–Acree model. Aqueous solutions of AEEA exhibit similar properties to the aqueous solutions of other alkanolamines (like monoethanolamine) used in acid gas sweetening. 相似文献