Hydrochloric Acid → 4-(3-Hydroxypropyl)benzene-1,3-diol

Temperatur

65 °C

To a stirred solution of 7-hydroxycoumarin (7.0 g, 43.2 mmol) in anhydrous THF (200 mL) at rt under argon was added Lithium borohydride (2M, 65.8 mL, 129.6 mmol, 3.0 eq) solution in THF dropwise. Anhydrous methanol (1.0 mL) was added as catalyst to the reaction mixture. The mixture was heated at 65° C. for 17 h. The reaction mixture was then cooled to ambient temperature. Saturated ammonium chloride solution (40 mL) was added dropwise to the solution, followed by 1N HCl solution (40 mL). The mixture was extracted with ethyl acetate (2×100 mL). The combined organic extracts were dried (Na2SO4), filtered, and evaporated in vacuo. The residue was purified on silica gel (flash column chromatography) eluting with 30% ethyl acetate-hexane to provide the desired product as white solid (3.05 g, 42%). 1H-NMR (CD3CN) δ 6.91 (d, 1H), 6.29 (s, 1H), 6.28 (d, 1H), 3.51 (t, 2H), 2.56 (t, 2H), 1.73 (m, 2H). MS GC-MS (M+=168).

1. temperatureThe reaction mixture was then cooled to ambient temperature
2. extractionThe mixture was extracted with ethyl acetate (2×100 mL)
3. dry with materialThe combined organic extracts were dried (Na2SO4)
4. filtrationfiltered
5. customevaporated in vacuo
6. customThe residue was purified on silica gel (flash column chromatography)
7. washeluting with 30% ethyl acetate-hexane

ORD-Eintrag

ord-1cb196f471ee484d99d9d9b90a88f357

Quelldatensatz

uspto-grants-2006_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07144885B2