Hydrochloric Acid → 2-Methyl-malonic acid monoethyl ester

First, 20.0 g of methylmalonic acid diethyl ester was dissolved in a mixed solution of 30 g of water and 30 g of ethanol. To this solution was added dropwise 9.6 g of 48% aqueous NaOH solution, and the mixture was vigorously stirred at room temperature for 7 hours. After completion of the reaction, the reaction solution was adjusted to pH 3 by the addition of 35% hydrochloric acid and concentrated under reduced pressure. To the residue was added 80 g of water, and the mixture was extracted twice with 40 g of ethyl acetate. The organic layers were combined and concentrated under reduced pressure. To the residue was added 100 g of n-hexane, and the precipitated crystals were collected by filtration. The filtrate was concentrated under reduced pressure to give 16.1 g of methylmalonic acid monoethyl ester.

1. customAfter completion of the reaction
2. concentrationconcentrated under reduced pressure
3. additionTo the residue was added 80 g of water
4. extractionthe mixture was extracted twice with 40 g of ethyl acetate
5. concentrationconcentrated under reduced pressure
6. additionTo the residue was added 100 g of n-hexane
7. filtrationthe precipitated crystals were collected by filtration
8. concentrationThe filtrate was concentrated under reduced pressure

ORD record

ord-370f252f07c84535b85c0748e0f6883d

Source dataset

uspto-grants-2001_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06204380B1