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211.
A reaction of 1-bromo-3,3,3-trichloro-1-nitropropene with pyrocatechol, o-aminophenol, and their substituted derivatives led to 2-nitromethyl-2-trichloromethyl-1,3-benzodioxoles and 2-nitromethyl-2-trichloromethyl-1,3-benzoxazolines. The structure of the compounds synthesized was established by IR, 1H and 13C NMR spectroscopy with HMQC and HMBC 1H—13C experiments, and X-ray diffraction analysis.  相似文献   
212.
The behavior of different anilines H2NC6H4R (R = o-Me, p-Me, o-, m- and p? i Pr, p-OMe, p-CO2Et) and 2,6-Me2C6H3NH2 towards trihalophosphoranes was studied. 2,6-Me2C6H3NH2 failed to form the diaminophosphonium salt [Ph2PNH(2,6-Me2C6H3)2]Br, and the aminophosphine oxide Ph2(2,6-Me2C6H3NH)PO was the only isolated product. Both o- and p-toluidine gave the corresponding diaminophosphonium salts; however in the case of o-toluidine, the yield was low and a mixture with the respective aminophosphine oxide was observed. Anilines containing methoxy and ethoxycarbonyl groups in para-position form the diaminophosphonium salts in reasonable yields.  相似文献   
213.
214.
Two phenyl‐substituted carboranes, 3‐phenyl‐1,2‐dicarba‐closo‐dodecaborane(12), C8H16B10, (I), and 1‐phenyl‐1,7‐dicarba‐closo‐dodecaborane(12), C8H16B10, (II), were found to be isostructural. Comparison of the bond angles at the ipso‐C atoms of the phenyl substituent for (I) and (II) [117.71 (3) and 118.45 (10)°, respectively] indicates that electron donation of the carborane cage for B‐ and C‐substituted carboranes is different.  相似文献   
215.
Interactions of acetylacetonatodicarbonylrhodium(1) with amidophosphito- and phosphitocavitands were studied. First representatives of tetranuclear cavity complexes of rhodium(1) were obtained. It was established by NMR spectroscopy and X-ray diffraction studies that the chemically identical phosphorhodium centers in these complexes differ in the spatial arrangement, and the system as a whole becomes unsymmetrical. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1852–1858, September, 1998.  相似文献   
216.
Alkylation of thiophosphorylacetonitriles under phase transfer catalysis conditions in the 50% NaOH/CH2Cl2 system proceeds as monoalkylation, whereas alkylation in MeCN with the use of solid KOH as a base gives a disubstituted product. The order in which the reagents were added as well as dilution of the reaction mixture affected substantially the yields of the target compounds. X-ray diffraction analysis of a single crystal of dibutyl(diphenylthiophosphoryl)acetonitrile was carried out. Deceased. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 990–996, May, 1998.  相似文献   
217.
218.
Birkedal  D.  Sayed  K. E.  Sanders  G.  Lyssenko  V. G.  Stanton  C.  Hvam  J. M. 《Il Nuovo Cimento D》1995,17(11):1359-1366
Il Nuovo Cimento D - The optical properties of multiple quantum wells in the transition from isolated wells to a superlattice are investigated theoretically and experimentally. For superlattices...  相似文献   
219.
Chiral dialkyl- and tetraalkylglycolurils have been obtained using chiral (S)-(+)- and (R)-(-)-1-sec-butyl-3-methylurea as starting materials. The diastereomer (S)-(+)-2,6-di-sec-butyl-4,8-dimethyl-2,4,6,8-tetraazabicyclo[3.3.0]-octane-3,7-dione was separated into stereoisomers, for the higher melting of which the absolute configuration was determined as (S,S,S,S) by X-ray structural analysis.  相似文献   
220.
Pentathiepinopyrroles reacted with methyl propiolate and triphenylphosphine to give regioselectively dithiinopyrroles in agreement with the electron distribution in the proposed reaction intermediate. Thieno[2,3-f][1,2,3,4,5]pentathiepin when treated with methyl propiolate and triphenylphosphine gave a pair of regioisomers where the higher yielding regioisomer contained the same mode of junction as in the case of pentathiepinopyrroles. X-ray crystal structures are provided for the thieno[2,3-b][1,4]dithiine carboxylate isomers. Quantum-chemical calculations B3LYP/6-31G(d) and B3LYP/6-311++G(d,p) have been carried out for better understanding of the reaction mechanisms; the index of synchronism of the Sh addition and the index of a relative difference in bond orders in transition states are in good agreement with the formation of the regioisomers by the reaction of unsymmetrical pentathiepins with alkynes containing one electron-withdrawing group.  相似文献   
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