Reaktion #77688

Reaktionsgleichung

(7α,14β,15β,17α)-3-methoxy-7-methyl-14,15-methyleneestra-2,5(10)-diene-17-methanol

oxalic acid

sodium hydrogencarbonate

→

(7α,14β,15β,17α)-17-(hydroxyethyl)-7-methyl-14,15-methyleneestr-5(10)-en-3-one

Lösungsmittel

methanol

tetrahydrofuran

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionthe product was extracted into ethyl acetate
2. 2
   WaschenThe combined organic phases were washed with brine
3. 3
   Trocknendried over sodium sulfate
4. 4
   Einengenconcentrated under reduced pressure

Vorschrift

A solution of (7α,14β,15β,17α)-3-methoxy-7-methyl-14,15-methyleneestra-2,5(10)-diene-17-methanol (Example 1, step vi; 7.38 g) in a mixture of methanol (68 ml) and tetrahydrofuran (48 ml) was treated with a solution of oxalic acid (2.38 g) in water (40 ml). After 1 h stirring at room temperature, the reaction mixture was poured into a saturated aqueous solution of sodium hydrogencarbonate and the product was extracted into ethyl acetate. The combined organic phases were washed with brine, dried over sodium sulfate and concentrated under reduced pressure. Column chromatography afforded (7α,14β,15β,17α)-17-(hydroxyethyl)-7-methyl-14,15-methyleneestr-5(10)-en-3-one (4.27 g). 1H NMR (CDCl3) δ3.69 (m, 1H), 3.51 (t, 1H, J=9.0 Hz), 2.72 (bs, 2H), 2.46 (bs, 2H), 1.04 (s, 3H), 0.69 (d, 3H, J=7.1 Hz), 0.48(dd, 1H, J=8.3 and 5.1 Hz), 0.27 (dd, 1H, J=5.1 and 3.1 Hz).

Quelle