[C:1]([O:7][CH3:8])(=[O:6])[CH2:2][C:3]([CH3:5])=O.[NH:9]1[CH2:13][CH2:12][CH2:11][CH2:10]1>C1(C)C=CC=CC=1.O.C1(C)C=CC(S(O)(=O)=O)=CC=1>[NH:9]1[CH2:13][CH2:12][CH2:11][CH:10]1[C:3]([CH3:5])=[CH:2][C:1]([O:7][CH3:8])=[O:6]Methyl acetoacetate (20 g, 172.23 mmol) was dissolved in 250 mL of toluene, and then pyrrolidine (43 ml, 516.70 mmol) and p-toluenesulfonic acid hydrate (about 100 mg) were added dropwise. After installing a Dean-Stark separator to the reactor, the reaction mixture was refluxed 140° C. for two days, and then solvent was removed by concentrating the resulting mixture under a reduced pressure, thereby to obtain the desired product (29 g, 99%).
Wird geladen…
