反应详情

A mixture of 15.8 g of ethyl 4-chloroacetoacetate (96.2 mmol) and 3.39 g of methanol (106 mmol) in 10 mL of THF were added dropwise to a stirred suspension of 4.62 g of 60% NaH (in mineral oil), 1.60 g of NaI (9.62 mmol), and 3.10 g of tetrabutylammonium bromide (9.62 mmol) in 40 mL of THF at −30° C. over a period of 1.5 hrs. The reaction mixture was then warmed to room temperature and stirred for 4 days. The reaction mixture was cooled to −30° C., quenched with 5 mL of methanol, and warmed to room temperature. The reaction mixture was poured into 0.5 L of 10% HCl solution, extracted with 2×100 mL of EtOAc, dried (Na2SO4), and the solvent was removed in vacuo. The crude product was distilled. The fraction boiling at 65-70° C. (0.3 mm Hg) was collected and used in the next experiments after spectral characterization.

1. temperatureThe reaction mixture was cooled to −30° C.
2. customquenched with 5 mL of methanol
3. temperaturewarmed to room temperature
4. additionThe reaction mixture was poured into 0.5 L of 10% HCl solution
5. extractionextracted with 2×100 mL of EtOAc
6. dry with materialdried (Na2SO4)
7. customthe solvent was removed in vacuo
8. distillationThe crude product was distilled
9. customThe fraction boiling at 65-70° C. (0.3 mm Hg) was collected