Potassium Sodium Tartrate → 3-(2-Hydroxy-ethyl)-benzofuran-6-ol

Temperature

0 °C

To a cooled (0° C.) solution of (6-hydroxy-benzofuran-3-yl)-acetic acid methyl ester (0.42 g, 2.0 mmol) in THF (18 mL) was added LAH (2 M in THF, 3.1 mL, 6.1 mmol) and the reaction mixture was stirred (0° C., 1 h). The reaction mixture was warmed (rt, 1 h). The reaction mixture was treated with Rochelle's salt (20 mL) and neutralized with saturated NH4Cl (20 mL). The aqueous layer was extracted with EtOAc (2×50 mL). The combined organic layers were washed with brine, dried, filtered and concentrated in vacuo. The resulting residue was purified by silica gel flash chromatography using MeOH:DCM (0-15%) to provide the title compound as a tan semisolid (0.34 g, 94%). 1H NMR (500 MHz, CDCl3): 7.41 (s, 1H), 7.37 (d, J=8.3, 1H), 6.95 (d, J=2.5, 1H), 6.78 (dd, J=8.3, 2.5, 1H), 3.93-3.91 (br s, 2H), 2.92-2.89 (m, 2H), the two hydroxyl protons were not detected.

1. temperatureThe reaction mixture was warmed (rt, 1 h)
2. extractionThe aqueous layer was extracted with EtOAc (2×50 mL)
3. washThe combined organic layers were washed with brine
4. customdried
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe resulting residue was purified by silica gel flash chromatography

ORD record

ord-b51f270ff5cf446180a62e6de180588b

Source dataset

uspto-grants-2013_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08399465B2