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21.
Diene condensations of 2-nitro-and 2-bromo-2-nitroethenylphosphonates with 2,3-dimethyl-1,3-butadiene, as well as with 2,4-dihydro-and 3-methyl-2,4-dihydrothiophene 1,1-dioxides that generate 1,3-butadiene and isoprene under the reaction conditions were effected. (6-Nitrocyclohex-3-en-1-yl)phosphonates and their dehydrogenation and/or dehydrohalogenation products, namely nitrocyclohexadienyl-and nitrophenylphosphonates were prepared. The structure of the obtained compounds was proved by IR and 1H and 31P NMR spectroscopy, and independent synthesis.  相似文献   
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New method for preparation of the previously unknown β-aminophosphonic acids of cyclohexane, norbornane, and bicyclooctane series from the corresponding nitrocycloalkenylphosphonates is developed. The structure of all compounds obtained is studied by the spectral (IR and 1H and 31P NMR) methods.  相似文献   
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Bis(2-chloroethyl) 2-nitro- and 2-bromo-2-nitroethenylphosphonates react with anthracene along two competing pathways: [4+2] cycloaddition and electrophilic substitution; in the case of the bromo derivative, the resulting products undergo dehydrobromination under the reaction conditions to form anthracene- and dihydroanthracene-containing nitroethenylphosphonates.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 5, 2005, pp. 729–733.Original Russian Text Copyright © 2005 by Anisimova, Kuzhaeva, Berkova, Deiko, Berestovitskaya.  相似文献   
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The diene condensation of β-nitro and β-bromo-β-nitroacrylates with 2-(2-nitroethenyl)furan as 1,3-diene leads to a mixture of regioisomeric tetrahydrobenzofurans transforming under the reaction conditions into benzofurancarboxylates due to the easy dehydrohalogenation, denitration, and dehydration. In the case of a gem-bromonitroacrylate reaction takes two routes: diene synthesis and alkylation of the furan ring, the latter process prevailing. The structure of products formed was established by spectral methods. The investigation of geometry of 2-(1-methoxycarbonyl-2-nitroethenyl)-5-(2-nitroethenyl)furan by XRD analysis showed that its vinyl fragments have the coplanar chelate-like structure with the cisoid orientation of the CO2Me and NO2 groups. The ester group deviates from the plane of the the carbon-carbon multiple bond.  相似文献   
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The temperature effect of the muon cosmic ray (CR) component is studied using the MUSTANG super telescope data (Greifswald, Germany) from 2007 throughout its period of operation. The original hourly data obtained with the telescope are adjusted for the temperature effect using a vertical atmospheric temperature profile at standard isobaric levels derived from the Global Forecast System (GFS) model. The model’s accuracy and applicability is evaluated using atmospheric sounding data collected over a number of years.  相似文献   
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Synthesis of a new representative of β-aminophosphonic acids and related esters, namely, 11-amino-9,10-dihydro-9,10-(ethano)anthracen-12-ylphosphonic acid and the respective bis(2-chloroethyl)-phosphonate was carried out.  相似文献   
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