反应详情

To a slurry of KH (400 mg, 35% in oil, 3.5 mmol) was added 5 mL of hexane. It was stirred for 5 min, and then the hexane was removed. This process was repeated three times. THF (5 mL) was added to this prewashed KH, and then 1-methylcyclobutanol (200 mg, 2.3 mmol) was added at 0° C. The mixture was stirred (0° C. to rt) for 1 h, and then carbonic acid dipyridin-2-yl ester (753 mg, 3.5 mmol) was added. The mixture was stirred at rt for 4 h, and the reaction was diluted with sat. aq. NH4Cl. The mixture was then extracted with EtOAc, and the solvent was removed in vacuo to obtain 200 mg of the crude carbonic acid 1-methyl-cyclobutyl ester pyridin-2-yl ester as an orange solid. It was used directly in the next step without further purification.

1. customthe hexane was removed
2. additionTHF (5 mL) was added to this prewashed KH
3. stirringThe mixture was stirred (0° C. to rt) for 1 h
4. stirringThe mixture was stirred at rt for 4 h
5. extractionThe mixture was then extracted with EtOAc
6. customthe solvent was removed in vacuo