Tetrahydrofuran → 5-(2-hydroxyethyl)-2-benzofuran-1(3H)-one

Participants

Reaction Steps

5-allyl-2-benzofuran-1(3H)-one (1.53 g, 8.78 mmol) was dissolved in methanol (30 mL). THF was added to solubilize the starting material. The resulting mixture was cooled in a dry ice acetone bath (−78° C.) and ozone was bubbled into the reaction until the color of the mixture changed to orange. Nitrogen was bubbled into the reaction for one minute to remove the excess ozone. Sodium borohydride (0.65 g, 2.9 mmol) was added at −78° C., and the reaction mixture was allowed to warm to ambient temperature. The reaction mixture was concentrated part way and then taken up in ethyl acetate and water. The layers were separated and the organic layer was washed with brine, dried over magnesium sulfate, filtered, and concentrated to provide 5-(2-hydroxyethyl)-2-benzofuran-1(3H)-one. 1H NMR (500 MHz, CD3OD) δ 7.77 (m, 1H), 7.37-7.41 (m, 2H), 5.23 (s, 2H), 3.92 (m, 2H), 2.99 (m, 2H).

Provenance & Evidence