反应详情

温度

-5 °C

In a 20 l vessel, 4.5 kg (32.6 mol) of potassium carbonate were suspended in 3.2 l of methyl tert-butyl ether and a liter of DMF. With stirring, the mixture was cooled to from 0 to −10° C. A solution of 4128 g (32 mol) of pentane-2,3,4-trione 3-oxime, 2 l of DMF and 4032 g (32 mol) of dimethyl sulfate was then metered in at an internal temperature of <25° C. over a period of 2 hours. The mixture was stirred at room temperature for another 3.5 hours. A further 20 l of water were then added, the upper, organic phase was removed, the aqueous phase was washed with 2 l of methyl tert-butyl ether, the combined organic phases were washed with 1 l of 5% strength hydrochloric acid and the solvent was distilled off. This gave 4214 g of the title compound in a purity of 96.6% (GC area percent), corresponding to a yield of 89%.

1. stirringThe mixture was stirred at room temperature for another 3.5 hours
2. customthe upper, organic phase was removed
3. washthe aqueous phase was washed with 2 l of methyl tert-butyl ether
4. washthe combined organic phases were washed with 1 l of 5% strength hydrochloric acid
5. distillationthe solvent was distilled off