反应详情

According to the general alkylation method, tert-butyl-2-acetoxy-aceto-acetate (219a) (7.12 g, 32.9 mmol), NaH (900 mg, 37.5 mmol) and propylbromide (4.05 g, 32.9 mmol) were reacted in DMF (64 mL) to give 2-acetoxy-2-acetyl-pentanoic-acid-tert-butylester (250h) (6.00 g, 23.2 mmol, 71%) as a slightly yellow oil after Kugelrohr distillation at 160° C. and 1.0 mbar. Then, 250h (6.00 g, 23.2 mmol) and 393 mg (2.07 mmol) p-TsOH.H2O were stirred in 60 mL benzene according to decarboxylation method A. Kugelrohr distillation at 1.0 mbar and 150° C., followed by column chromatography (diethylether:petroleum ether=1:8) gave 251h (2.00 g, 12.6 mmol, 54%) as a colorless oil.