Methyl acetoacetate → Methyl 4-bromo-3-oxobutanoate

Temperature

0 °C

In 2613 g of 1-chlorobutane was dissolved 523 g of methyl acetoacetate and cooled to 0° C. To this mixture was dropwise added 719 g of bromine at 5±5° C. over a period of one hour, and the mixture was thereafter kept at that temperature for four hours. The reaction mixture was washed with 1161 g of a 10% saline solution. After separating the mixture into an aqueous and organic layers, concentration of the organic layer in vacuous at a temperature of 40° C. or less gave 782.9 g of crude methyl 4-bromoacetoacetate. The gas chromatography analysis indicated that the content of methyl 4-bromoacetoacetate in the crude product was 72% (564 g, 64% yield).

1. customat 5±5° C.
2. customof one hour
3. washThe reaction mixture was washed with 1161 g of a 10% saline solution
4. customAfter separating the mixture into an aqueous and organic layers, concentration of the organic layer in vacuous at a temperature of 40° C. or less

ORD record

ord-3d730118bc544e419018991a648f68c2

Source dataset

uspto-grants-2002_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06469200B1