Reaktion #700311

Reaktionsgleichung

hydrochloric acid

tetrahydrofuran

4-[4-Hydroxy-5-[(2-isopropylphenyl)thio]-6-oxo-6H-pyran-2-yl]phenoxy acetic acid ethyl ester

sodium hydroxide

→

4-[4-Hydroxy-5-[(2-isopropylphenyl)thio]-6-oxo-6H-pyran-2-yl]-phenoxy acetic acid

Lösungsmittel

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   ExtraktionThe aqueous layer was then extracted 2× with ethyl acetate (100 ml)
2. 2
   Waschenthe combined organic extracts were then washed with saturated sodium chloride
3. 3
   Trocknendried over anhydrous magnesium sulfate
4. 4
   SonstigeAfter evaporation of the solvents in vacuo
5. 5
   Sonstigethe crude product was purified by column chromatography (silica gel-230 to 400 mesh)

Vorschrift

To a tetrahydrofuran (10 ml) solution of 4-[4-Hydroxy-5-[(2-isopropylphenyl)thio]-6-oxo-6H-pyran-2-yl]phenoxy acetic acid ethyl ester (0.319 g. 0.75 mmol) was added 1N sodium hydroxide (1.80 mL, 1.81 mmol). The reaction was stirred for 1.5 h, and then water (10 ml) was added followed by acidification with conc. hydrochloric acid to pH 2. The aqueous layer was then extracted 2× with ethyl acetate (100 ml). the combined organic extracts were then washed with saturated sodium chloride and dried over anhydrous magnesium sulfate. After evaporation of the solvents in vacuo, the crude product was purified by column chromatography (silica gel-230 to 400 mesh) using 94/5/1 methylene chloride/methanol/acetic acid as the eluent. m.p. 217° C.; (dec.); 1H NMR (400 MHz, DMSO-d6) δ 1.25 (d, 6H), 3.42 (m, 1H), 4.79 (s, 2H), 6.75 (s, 1H), 6.90 (d, 1H), 7.06 (m, 4H), 7.26 (d, 1H), 7.79 (d, 2H).

Quelle