反应详情

Refer to FIG. 189. Jones reagent (2.67 M, 0.88 ml, 2.3 mmol) was added to a solution of 17β-methylandrost-5-en-3β-ol (5, 135.5 mg, 0.4697 mmol) (J. B. Jones and K. D. Gordon, Can. J. Chem. 1972, 50, 2712-2718) in acetone (15 ml) and the mixture was 10 stirred 45 min. The reaction was quenched with the addition of 2-propanol (0.44 ml). After stirring a further 10 min. the reaction mixture was poured into 30 ml of water and extracted with three 15 ml portions of ethyl acetate. The combined organic extracts were washed with 15 ml of saturated sodium bicarbonate+15 ml of brine, dried over magnesium sulfate, and filtered through diatomaceous earth. The residue was washed with 10 ml of ethyl acetate and the combined filtrates were concentrated under reduced pressure. Preparative TLC (silica gel GF, 1000μ, 25% ethyl acetate/hexanes as eluent), and recrystallization from aqueous ethanol gave lustrous off-white crystals (37.5 mg, 0.125 mmol, 27%), m.p. 94-95° C., homogeneous to TLC (25% ethyl acetate/hexanes on silica gel, Rf 0.39).

1. customThe reaction was quenched with the addition of 2-propanol (0.44 ml)
2. stirringAfter stirring a further 10 min. the reaction mixture
3. additionwas poured into 30 ml of water
4. extractionextracted with three 15 ml portions of ethyl acetate
5. washThe combined organic extracts were washed with 15 ml of saturated sodium bicarbonate+15 ml of brine
6. dry with materialdried over magnesium sulfate
7. filtrationfiltered through diatomaceous earth
8. washThe residue was washed with 10 ml of ethyl acetate
9. concentrationthe combined filtrates were concentrated under reduced pressure
10. customPreparative TLC (silica gel GF, 1000μ, 25% ethyl acetate/hexanes as eluent), and recrystallization from aqueous ethanol