Hydrogen Bromide → 2beta-Bromo-3alpha-hydroxy-17beta-methoxycarbonyl-5alpha-androstan-11-one
反応式
[O:1]1[C@H:3]2[CH2:4][C@H:5]3[C@:18]([CH3:20])([CH2:19][C@@H:2]12)[C@@H:17]1[C@H:8]([C@H:9]2[C@@:13]([CH2:15][C:16]1=[O:21])([CH3:14])[C@@H:12]([C:22]([O:24][CH3:25])=[O:23])[CH2:11][CH2:10]2)[CH2:7][CH2:6]3.[BrH:26]>C(Cl)(Cl)Cl>[Br:26][C@H:2]1[CH2:19][C@@:18]2([CH3:20])[C@@H:5]([CH2:6][CH2:7][C@@H:8]3[C@@H:17]2[C:16](=[O:21])[CH2:15][C@@:13]2([CH3:14])[C@H:9]3[CH2:10][CH2:11][C@@H:12]2[C:22]([O:24][CH3:25])=[O:23])[CH2:4][C@@H:3]1[OH:1]参加物
4
実験手順
2α,3α-Epoxy-17β-methoxycarbonyl-5α-androstan-11-one (500 mg.) in chloroform (32 ml.) was stirred with 48% aqueous hydrogen bromide (10 ml.). After an hour the mixture was washed with an excess of aqueous sodium bicarbonate and with water, was dried (MgSO4) and evaporated to a froth (628 mg.) Crystallisation from ethyl acetate/light petroleum afforded title compound (330 mg.) as colourless needles; m.p. 205°-208°; [α]D + 76°,