摘要
The reactions of perfluoroalkanesulfonyl bromide with a,β-unsaturated esters were studied in detail. The reaction products were further converted to a series of perfluoroalkyl-substituted a, β-unsaturated acids or esters, a-amino acids and γ-lactones. A peculiar peak (M+15)was found to appear in the mass spectra of some perfluoroalkyl-substituted methyl esters. It was interpreted to be the result of a CH_3 group transfer to the molecular ion. Magnetic nonequivalence was observed in the ^(19)F NMR spectra of CF_2 group linked to CH_2 in compounds 2t, g and 3t', g which showed a typical AB pattern, and was attributed to the effect of steric hindrance.
The reactions of perfluoroalkanesulfonyl bromide with a,β-unsaturated esters were studied in detail. The reaction products were further converted to a series of perfluoroalkyl-substituted a, β-unsaturated acids or esters, a-amino acids and γ-lactones. A peculiar peak (M+15)was found to appear in the mass spectra of some perfluoroalkyl-substituted methyl esters. It was interpreted to be the result of a CH_3 group transfer to the molecular ion. Magnetic nonequivalence was observed in the ^(19)F NMR spectra of CF_2 group linked to CH_2 in compounds 2t, g and 3t', g which showed a typical AB pattern, and was attributed to the effect of steric hindrance.
