反应详情

温度

-78 °C

To a cooled (−78° C.) solution of 1,4-dioxaspiro[4.5]decan-8-one (1 equiv) in THF (0.64 M) was added a solution of methylmagnesium bromide (1.8 equiv, 3 mol/L in ether) dropwise under nitrogen atmosphere. The resulting mixture was stirred at −78° C. for 20 minutes, then warmed to −30° C. for 30 minutes and then stirred at 0° C. for 30 minutes. After the reaction was complete, the resulting mixture was quenched with saturated aqueous ammonia chloride solution and extracted with ethyl acetate. The organic layers were combined, washed with brine, dried over sodium sulfate, filtered and concentrated to afford the title compound as a white solid (92% yield), which was used in the next step without further purification. 1H NMR (300 MHz, CHLOROFORM-d1) δ ppm 4.00-3.91 (m, 4H), 1.95-1.80 (m, 3H), 1.77-1.67 (m, 4H), 1.59-1.58 (m, 1H), 1.27 (s, 3H), 1.17 (s, 1H).

1. temperaturewarmed to −30° C. for 30 minutes
2. stirringstirred at 0° C. for 30 minutes
3. customthe resulting mixture was quenched with saturated aqueous ammonia chloride solution
4. extractionextracted with ethyl acetate
5. washwashed with brine
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated