反应详情

Methyl 2,4-dihydroxy-3-formylbenzoate (10.0 g, 0.051 M) was added to dimethylformamide (100 ml), then to this mixture was added sodium hydride (1.344 g, 0.056 M), portionwise. The mixture became warm and effervescence occurred. When the addition was complete the reaction mixture was left to stir at room temperature for 10 minutes. To this solution was then added sodium iodide (0.765 g), ethyl 5-bromovalerate (11.7 g, 0.056 M), and a further 20 ml of dimethylformamide. The whole was brought to 60° C. and left to stir for 5 days. The reaction mixture was cooled, poured into water (200 ml), acidified with concentrated hydrochloric acid, and extracted into ethyl acetate (2×75 ml). The combined organic layers were washed with water (2×75 ml), 5% sodium hydroxide solution (50 ml), water (50 ml) and brine (50 ml), dried (magnesium sulphate), filtered and the solvent removed in vacuo to give ethyl 5-(2-formyl-3-hydroxy-4-methoxycarbonylphenoxy)pentanoate 6.92 g, 42% as a yellow oil, purified by column chromatography and obtained as a pale-yellow solid.

1. temperatureThe mixture became warm
2. additionWhen the addition
3. waitwas left
4. customwas brought to 60° C.
5. waitleft
6. stirringto stir for 5 days
7. temperatureThe reaction mixture was cooled
8. extractionextracted into ethyl acetate (2×75 ml)
9. washThe combined organic layers were washed with water (2×75 ml), 5% sodium hydroxide solution (50 ml), water (50 ml) and brine (50 ml)
10. dry with materialdried (magnesium sulphate)
11. filtrationfiltered
12. customthe solvent removed in vacuo