反应详情

温度

85 °C

2-Bromo-1,1-diethoxyethane (0.31 mL) was added to a mixture of methyl 4-hydroxy-2,5-dimethylbenzoate (example 18, step b) (0.25 g) and caesium carbonate (0.68 g) in DMF (20 mL). The resulting mixture was stirred at 85° C. for 16 h. The reaction was partitioned between water (200 mL) and ethyl acetate (100 mL). The aqueous phase was separated and extracted with ethyl acetate (2×100 mL). The combined organic solutions were washed with water (2×100 mL) and brine (100 mL), dried over magnesium sulphate, filtered and evaporated. The residue was purified by silica gel chromatography eluting with isohexane to 10:1 isohexane:ethyl acetate gradient. The fractions containing product were combined and evaporated in vacuo to give the subtitled compound as a clear oil. Yield 0.26 g.

1. customThe reaction was partitioned between water (200 mL) and ethyl acetate (100 mL)
2. customThe aqueous phase was separated
3. extractionextracted with ethyl acetate (2×100 mL)
4. washThe combined organic solutions were washed with water (2×100 mL) and brine (100 mL)
5. dry with materialdried over magnesium sulphate
6. filtrationfiltered
7. customevaporated
8. customThe residue was purified by silica gel chromatography
9. washeluting with isohexane to 10:1 isohexane
10. additionThe fractions containing product
11. customevaporated in vacuo