反应详情

2-Isobutylmalonic acid ethyl ester methyl ester (50.0 g, 231 mmol, 1.0 eq) was dissolved into 280 ml ethanol. To this solution was added solid KOH (12.7 g, 226 mmol, 0.98 eq) and the mixture was stirred at room temperature for 16 hours. The mixture was then concentrated under reduced pressure and redissolved in 500 mL water. The solution was washed 2×250 ml diethyl ether, acidified to pH 2 with 6N HCl, and extracted with 2×250 mL diethyl ether. The organic was dried over MgSO4, and concentrated to yield intermediate (3a) (40.3 g). 1H NMR (DMSO) δ (ppm): 1.0 (dd, 6H), 1.2 (t, 1H), 1.3 (t, 3H), 1.5-1.7 (m, 1H), 1.8 (t, 2H), 3.5 (m, 2H), 4.2 (quart, 2H).

1. concentrationThe mixture was then concentrated under reduced pressure
2. dissolutionredissolved in 500 mL water
3. washThe solution was washed 2×250 ml diethyl ether
4. extractionextracted with 2×250 mL diethyl ether
5. dry with materialThe organic was dried over MgSO4
6. concentrationconcentrated