The nitration of 5,7-dimethyl-2-polyhaloalkylchromones affords either 5,7-dimethyl-6-nitro- or 5,7-dimethyl-6,8-dinitro-2-polyhaloalkylchromones, depending on the reaction conditions. Signals in the H-1 and C-13 NMR spectra of the sterically hindered chromones were completely assigned using the 2D NOESY, HETCOR, and COLOC spectra. The influence of nonplanar nitro groups on chemical shifts of carbon atoms was studied. Some spectral peculiarities of the peri-methyl group were revealed. The H-1-H-1 and C-13-H-1 spin-spin coupling constants, including the extreme six-bond long-range coupling between the protons of the Me(5) group and H(8), were determined.
Synthese de F-alkyl-2 chromones et mise en evidence de leurs intermediaires reactionnels.
作者:V. Bayer、R.E. Pastor、A.R. Cambon
DOI:10.1016/s0022-1139(00)82275-7
日期:1982.6
BAYER, V.;PASTOR, R. E.;CAMBON, A. R., J. FLUOR. CHEM., 1982, 20, N 4, 497-505
作者:BAYER, V.、PASTOR, R. E.、CAMBON, A. R.
DOI:——
日期:——
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作者:V. Ya. Sosnovskikh、B. I. Usachev、M. I. Kodess
DOI:10.1023/a:1021340132279
日期:——
The nitration of 5,7-dimethyl-2-polyhaloalkylchromones affords either 5,7-dimethyl-6-nitro- or 5,7-dimethyl-6,8-dinitro-2-polyhaloalkylchromones, depending on the reaction conditions. Signals in the H-1 and C-13 NMR spectra of the sterically hindered chromones were completely assigned using the 2D NOESY, HETCOR, and COLOC spectra. The influence of nonplanar nitro groups on chemical shifts of carbon atoms was studied. Some spectral peculiarities of the peri-methyl group were revealed. The H-1-H-1 and C-13-H-1 spin-spin coupling constants, including the extreme six-bond long-range coupling between the protons of the Me(5) group and H(8), were determined.