Potassium Carbonate → 5-Cholesten-3beta-ol benzoate
反応式
[CH3:1][CH:2]([CH2:4][CH2:5][CH2:6][C@H:7]([C@@H:9]1[C@:26]2([CH3:27])[C@H:12]([C@H:13]3[C@H:23]([CH2:24][CH2:25]2)[C@:21]2([CH3:22])[C:16]([CH2:17][C@@H:18]([OH:28])[CH2:19][CH2:20]2)=[CH:15][CH2:14]3)[CH2:11][CH2:10]1)[CH3:8])[CH3:3].S=[C:30]1[CH:38]=[CH:37][CH:36]=[CH:35][CH:31]1[C:32]([O-:34])=[O:33].C(=O)([O-])[O-].[K+].[K+]>C(Cl)(Cl)Cl>[CH3:3][CH:2]([CH2:4][CH2:5][CH2:6][C@H:7]([C@@H:9]1[C@:26]2([CH3:27])[C@H:12]([C@H:13]3[C@H:23]([CH2:24][CH2:25]2)[C@:21]2([CH3:22])[C:16]([CH2:17][C@@H:18]([OH:28])[CH2:19][CH2:20]2)=[CH:15][CH2:14]3)[CH2:11][CH2:10]1)[CH3:8])[CH3:1].[C:32]([O-:34])(=[O:33])[C:31]1[CH:35]=[CH:36][CH:37]=[CH:38][CH:30]=1参加物
4
実験手順
5-Cholesten-3β-ol-thionobenzoate (100 mg, 0.198 mmol), symdibromo-tetrachloroethane (323 mg, 0.991 mmol), and 4-methoxy-4'-dimethylaminodiphenyltellurium dichloride (8.4 mg, 0.0198 mmole) were stirred in a two phase system of chloroform (2 ml) and aqueous potassium carbonate (2.5 ml, 20%) at room temperature for 4 h. T.l.c. (petroleum ether followed by petroleum ether-ethyl acetate 20:1) showed complete reaction. The two phases were separated, the aqueous phase extracted with chloroform (2×5 ml) and the combined chloroform extracts dried over magnesium sulphate. Filtration, evaporation of the solvent and column chromatography (petroleum ether followed by petroleum ether-ethyl acetate 20:1) of the residue afforded 5-cholesten-3β-ol-benzoate (85 mg, 88%) m.p. 143°-145° (lit; 150°-151°). The i.r. spectrum was identical to that of an authentic sample.