Potassium vinyltrifluoroborate → 5-Ethenyl-7-fluoro-1(3H)-isobenzofuranone

Participants

Reaction Steps

A mixture of 5-bromo-7-fluoro-2-benzofuran-1(3H)-one (4.6 g, 20.0 mmol), potassium vinyltrifluoroborate (2.9 g, 22 mmol) and Pd (dppf)2Cl2 (0.5 g) in 40 mL of EtOH and 40 mL of TEA was refluxed under Ar for 4 hours. After concentration, the residue was purified by column chromatography (PE:EtOAc=20:1) to afford 7-fluoro-5-vinyl-2-benzofuran-1(3H)-one. 1H-NMR (400 MHz, CDCl3) δ ppm 7.23 (s, 1H), 7.17 (d, J=10.0 Hz, 1H), 6.70-6.77 (m, 1H), 5.89 (d, J=17.2 Hz, 1H), 5.51 (d, J=11.2 Hz, 1H), 5.28 (s, 2H).

Provenance & Evidence