反应详情

温度

75 °C

To a stirred solution of (3aS,4R,6aR,7R,10R,10aR)-7-(2,2-dichloro-1-methylethenyl)-2,2,5,10-tetramethyl-4,6a,7,8, 9,10-hexahydro-3aH-naphtho[1,8a-d][1,3]dioxol-4-yl acetate (Preparation 170, 0.95 g) in ethylene glycol (40 ml) and methanol (10 ml) was added para-toluenesulphonic acid (95 mg). The reaction mixture was heated to 75° C., after 1.5 h the reaction mixture was concentrated in vacuo to remove the methanol. The resultant solution was diluted with diethyl ether (30 ml) and water (30 ml) and the organic layer separated and washed with sodium hydrogen carbonate (3×30 ml). The aqueous layers were back extracted with diethyl ether (2×20 ml) and the combined organic extracts were dried (MgSO4) and concentrated to give the title compound as a white solid.

1. concentrationwas concentrated in vacuo
2. customto remove the methanol
3. additionThe resultant solution was diluted with diethyl ether (30 ml) and water (30 ml)
4. customthe organic layer separated
5. washwashed with sodium hydrogen carbonate (3×30 ml)
6. extractionThe aqueous layers were back extracted with diethyl ether (2×20 ml)
7. dry with materialthe combined organic extracts were dried (MgSO4)
8. concentrationconcentrated