β,β-Dinitrostyrenes: Specificity of synthesis and structure
摘要:
An improved procedure was developed for the synthesis of beta,beta-dinitrostyrenes, which increased the yield and reproducibility and made the products more accessible from the preparative viewpoint. Complex analysis of the spectral data (IR, UV, H-1 and C-13 NMR) and results of quantum-chemical calculations showed that 2-aryl-1,1-dinitroethene molecules have a structure in which one nitro group resides in the C=C bond plane while the other deviates from this plane. The C=C bond in 2-aryl-1,1-dinitroethene molecules was found to possess enhanced polarization and electrophilicity as compared to the corresponding bond in model mononitrostyrenes.
The synthesis of functionalized GEM-dinitrocyclopropanes via [3+2] cycloaddition of diazocarbonylcompounds with 1,1-dinitroethenes [in some cases in the presence of Mo(CO) 6 as catalyst] has been developed.
The preparation of the geometrical isomers of ethyl α-nitrocinnamate and α-nitrochalcone is described. Ethyl (E)-α-nitrocinnamate and (Z)-α-nitrochalcone were obtained by the thermal- or photoisomerization of the corresponding geometrical isomers, which were themselves produced predominantly through the Knoevenagel reaction. The facile addition of ethanol to the double bonds of β,β-dinitrostyrene,
β,β-Dinitrostyrenes in reactions with cyclohexane-1,3-diones
作者:E. V. Trukhin、E. A. Sheremet、V. M. Berestovitskaya
DOI:10.1007/s11172-009-0278-x
日期:2009.10
The Michael-type addition of dimedone and dihydroresorcinol to β,β-dinitrostyrenes occurs easily without a catalyst. The adducts cyclize into 3-aryl-2-nitro-2,3,4,5,6-hexahydrobenzofuran-4-ones under the action of triethylamine.