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

Temperature

-78 °C

5-(Prop-2-en-1-yl)-2-benzofuran-1(3H)-one (1.53 g, 8.78 mmol) was dissolved in a mixture of methanol (30 mL) with just enough THF to solubilize the starting material and was cooled to −78° C. Ozone was bubbled through the solution until the reaction mixture color changed (to orange). Then nitrogen gas was bubbled through the reaction mixture for about one min. to remove the residual ozone. Sodium borohydride (0.65 g, 17 mmol) was added and the mixture was allowed to warm to room temperature. The reaction mixture was partially concentrated then was partitioned between ethyl acetate and water. The organic layer was washed with brine, then dried over MgSO4. The crude product was purified by MPLC (silica) eluting with ethyl acetate to afford pure product. LCMS: m/z 179 (M+1)+; 1H NMR (500 MHz, CD3OD) δ 7.77 (m, 1H), 7.37-7.41 (m, 2H), 5.23 (s, 2H), 192 (m, 2H), 2.99 (m, 2H).

1. customOzone was bubbled through the solution until the reaction mixture color
2. customThen nitrogen gas was bubbled through the reaction mixture for about one min.
3. customto remove the residual ozone
4. temperatureto warm to room temperature
5. concentrationThe reaction mixture was partially concentrated
6. customthen was partitioned between ethyl acetate and water
7. washThe organic layer was washed with brine
8. dry with materialdried over MgSO4
9. customThe crude product was purified by MPLC (silica)
10. washeluting with ethyl acetate
11. customto afford pure product

ORD record

ord-4b189d55554f44dfae8ba9ab35cec13c

Source dataset

uspto-grants-2015_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09056859B2