反应详情

To a chilled (0° C.) solution of lithium bis(trimethylsilyl)amide (1.0 M, 56 mL) was dropwise added a solution of trimethylphosphonoacetate, keeping the temperature below 10° C. The solution was then allowed to warm to room temperature and stirred for an additional five minutes after which a solution of p-isobutylacetophenone in THF (25 mL) was added in one portion. The solution was slowly heated to 65° C. and allowed to reflux for thirty hours. The solution was cooled to room temperature then diluted with a 10% NH4Cl solution (100 mL), and extracted with ethyl acetate (2×100 mL). The organic layers were combined and dried over MgSO4, filtered, and filtrate concentrated to a white solid which was recrystallized from hexane/ethyl acetate to give 5.93 grams of 3-(4-isobutylphenyl)but-2-enoic acid methyl ester intermediate (89.9% yield).

1. customthe temperature below 10° C
2. additionwas added in one portion
3. temperatureThe solution was slowly heated to 65° C.
4. temperatureto reflux for thirty hours
5. temperatureThe solution was cooled to room temperature
6. extractionextracted with ethyl acetate (2×100 mL)
7. dry with materialdried over MgSO4
8. filtrationfiltered
9. concentrationfiltrate concentrated to a white solid which
10. customwas recrystallized from hexane/ethyl acetate