反应详情

5α-Pregnane 3,20-dione (10 g) is reacted with a reagent obtained by reacting FeCl3 (5.2 g) and MeMgCl (4 equiv, based on FeCl3) in t-butyl methyl ether (anhydrous, 200 mf) at −25° C. for 3h. The reaction is quenched with acetic acid (32 ml). The reaction mixture is concentrated in vacuo and the residue is stirred with 3N HCI for 6 h. The solid is collected by filtration, washed with water and dried at 50° C. under vacuum to obtain crude ganaxolone. The crude product is dissolved in THF (33 mL) at reflux and filtered not. The filtrate is added with water (45 mL) to obtain a suspension, which is collected by filtration, washed with water and dried. The dried product is further slurried in ethyl acetate (50 mL) at 70° C. for 19 h, The suspension is cooled to 0° C. and filtered. The ethyl acetate slurry step was repeated second time to obtain purified ganaxolone.

1. customobtained
2. customat −25° C.
3. customfor 3h
4. customThe reaction is quenched with acetic acid (32 ml)
5. concentrationThe reaction mixture is concentrated in vacuo
6. filtrationThe solid is collected by filtration
7. washwashed with water
8. customdried at 50° C. under vacuum