Hydrochloric Acid → Methyl 4-methoxyacetoacetate

Temperature

23 °C

In a 2 liter four-necked flask were charged 88.0 g (2.2 mol) of 60% sodium hydride and 753 ml of tetrahydrofuran in a nitrogen stream, and a mixture of 150.6 g (1.0 mmol) of methyl 4-chloro-3-oxo-butyrate and 35.2 g (1.1 mol) of methanol was added thereto dropwise at room temperature (22 to 24° C.). After the addition, the mixture was stirred at room temperature (22 to 24° C.) for 1 hour. The reaction mixture was cooled with ice, and 600 ml (1.2 mol) of 2N hydrochloric acid was added dropwise. The tetrahydrofuran was recovered from the reaction mixture, and 400 ml of toluene was added to the residue. The aqueous phase was extracted with three 200 ml portions of toluene. The organic phase was washed with a 5% sodium chloride aqueous solution, and the solvent was evaporated under reduced pressure. The residue was distilled under reduce pressure (boiling point: 90° C./1000 Pa) to give 107.7 g (74%) of methyl 4-methoxy-3-oxobutyrate as liquid.

1. additionwas added
2. customdropwise at room temperature
3. custom(22 to 24° C.)
4. additionAfter the addition
5. additionwas added dropwise
6. customThe tetrahydrofuran was recovered from the reaction mixture, and 400 ml of toluene
7. additionwas added to the residue
8. extractionThe aqueous phase was extracted with three 200 ml portions of toluene
9. washThe organic phase was washed with a 5% sodium chloride aqueous solution
10. customthe solvent was evaporated under reduced pressure
11. distillationThe residue was distilled

ORD record

ord-e0a79fa3354545b99a7c0bc05d6180cd

Source dataset

uspto-grants-2002_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06403804B1