2-Polyfluoroalkylchromones 10. Synthesis of regioisomeric 3-(2-hydroxyaryl)-5-polyfluoroalkyl- and 5-(2-hydroxyaryl)-3-polyfluoroalkylisoxazoles and determination of their structures by ¹H, ¹⁹F, and ¹³C NMR spectroscopy

Abstract:

The reactions of 2-hydroxy-2-polyfluoroalkylchroman-4-ones with hydroxylamine yield, through Δ2-isoxazolines as intermediate products, 3-(2-hydroxyaryl)-5-polyfluoroalkylisoxazoles. Analogous reactions with 2-polyfluoroalkylchromones afford β-diketone monooximes, which in an acidic medium undergo cyclodehydration into 5-(2-hydroxyaryl)-3-polyfluoroalkylisoxazoles. The structures of regioisomeric 3- and 5-polyfluoroalkylisoxazoles were determined using 1H, 19F, and 13C NMR spectroscopy.

Año de publicación:

2002

Keywords:

• 2-hydroxy-2-polyfluoroalkylchroman-4-ones
• Hydroxylamine hydrochloride
• 5-polyfluoroalkylisoxazoles
• 5-hydroxy-5-polyfluoroalkyl-Δ -isoxazolines 2
• 2-polyfluoroalkylchromones
• 3-polyfluoroalkylisoxazoles
• β-diketone monooximes

Fuente:

scopus