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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

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).

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