反应详情

To a stirred solution of ethyl 5-(2-formyl-3-methoxyphenoxy)-2,2-dimethylpentanoate (6.46 g, 0.021 M) in dry tetrahydrofuran (60 ml) was added dropwise a solution of magnesium iodide (8.67 g, 0.031 M) in dry ether (130 ml). The mixture was then stirred under reflux (51/2 hr). The cooled mixture, containing ethyl 5-(2-formyl-3-hydroxyphenoxy)-2,2-dimethylpentanonate, was poured into 10% hydrochloric acid (110 ml). The organic layer was separated and the aqueous phase extracted with ethyl acetate. The combined organic solutions were washed with water, dried (sodium sulphate) and evaporated. The residue was dissolved in 95% ethanol (50 ml) and 2 N sodium hydroxide solution (100 ml) and stirred at room temperature (20 hr). The solution was then evaporated and the residue diluted with water and extracted with ether. The aqueous phase was acidified with concentrated hydrochloric acid with cooling and the solid produced filtered off and washed with water to give 5-(2-formyl-3-hydroxyphenoxy)-2,2-dimethylpentanoic acid, m.p. 76°-77° C. from benzene/petrol.

1. temperatureunder reflux (51/2 hr)
2. customThe organic layer was separated
3. extractionthe aqueous phase extracted with ethyl acetate
4. washThe combined organic solutions were washed with water
5. dry with materialdried (sodium sulphate)
6. customevaporated
7. dissolutionThe residue was dissolved in 95% ethanol (50 ml)
8. stirring2 N sodium hydroxide solution (100 ml) and stirred at room temperature (20 hr)
9. customThe solution was then evaporated
10. additionthe residue diluted with water
11. extractionextracted with ether
12. temperaturewith cooling
13. customthe solid produced
14. filtrationfiltered off
15. washwashed with water