Ethanol → Ethyl 2-amino-2-methylpropanoate hydrochloride

Temperature

20 °C

Ethanol (395 L) was added to 2-aminoisobutyric acid (79 Kg) and the mixture stirred at 20° C. Thionyl chloride (91.2 Kg) was added, maintaining the temperature at 540° C. The mixture was heated to reflux and stirred for 6 hours. The contents were distilled under atmospheric pressure to a residual volume of approximately 200 L over a period of 14 hours. The mixture was cooled to 45-50° C. and methyl tert-butyl ether (395 L) was added. The mixture was cooled to 0-5° C. and stirred for 1 hour. Material was isolated by filtration and washed with methyl tert-butyl ether (160 L) pre-cooled to 0-5° C., then dried in vacuo at 30-40° C. to give ethyl-2-aminoisobutyrate hydrochloride (105.5 Kg) with 86.2% purity in 71% yield (based on active).

1. temperaturemaintaining the temperature at 540° C
2. temperatureThe mixture was heated
3. temperatureto reflux
4. stirringstirred for 6 hours
5. distillationThe contents were distilled under atmospheric pressure to a residual volume of approximately 200 L over a period of 14 hours
6. temperatureThe mixture was cooled to 45-50° C.
7. additionmethyl tert-butyl ether (395 L) was added
8. temperatureThe mixture was cooled to 0-5° C.
9. stirringstirred for 1 hour
10. customMaterial was isolated by filtration
11. washwashed with methyl tert-butyl ether (160 L)
12. temperaturepre-cooled to 0-5° C.
13. customdried in vacuo at 30-40° C.

ORD record

ord-b59898afe3f6419392f0f06c53894fbf

Source dataset

uspto-grants-2015_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09067944B2