反应详情

温度

5 °C

A solution of cyclopentanecarbonyl chloride (1.100 mL, 9.05 mmol) in DCM (5 mL) was added dropwise to a stirred solution of isopropylidene malonate (1.304 g, 9.05 mmol), and pyridine (1.464 mL, 18.10 mmol) in DCM (20 mL) at 5° C., over a period of 10 minutes under nitrogen. The resulting solution was stirred at 5° C. for 1 hour and then allowed to warm to 20° C. and stirred for another hour. The reaction mixture was diluted with DCM (100 mL), and washed sequentially with 2M HCl (2×50 mL), water (50 mL), and saturated brine (50 mL). The organic layer was dried over MgSO4, filtered and evaporated to afford crude product, 5-(cyclopentanecarbonyl)-2,2-dimethyl-1,3-dioxane-4,6-dione (2.100 g, 97%) as a brown oil.

1. temperatureto warm to 20° C.
2. stirringstirred for another hour
3. washwashed sequentially with 2M HCl (2×50 mL), water (50 mL), and saturated brine (50 mL)
4. dry with materialThe organic layer was dried over MgSO4
5. filtrationfiltered
6. customevaporated