Hydrochloric Acid → beta-Aminobeta-ethoxyacrylic acid ethyl ester

In an oven-dried flask were placed 113.1 g of redistilled ethyl cyanoacetate, 46 g of ethanol (distilled from calcium hydride), and 500 ml of anhydrous diethyl ether. The solution was cooled to 0°, 36.5 g of hydrogen chloride gas were added and the flask was sealed. The mixture was refrigerated for several days until precipitation of white solid was observed. The white precipitate was collected by filtration and immediately resuspended in approximately 300 ml of diethyl ether. The ether-suspension was mixed with 1000 ml of a 40% aqueous solution of potassium carbonate (previously cooled to 0°). The ether layer was separated and placed over 30 g of anhydrous potassium carbonate. The aqueous phase was washed three times with 150 ml portions of diethyl ether. The washings were added to the ether phase over potassium carbonate. The combined ether phase and washings were decanted onto approximately 80 g of fresh anhydrous potassium carbonate. The potassium carbonate was removed by filtration and the ether was removed by evaporation under reduced pressure. The residue was distilled at 0.25 mm hg. The fraction distilling at 60° was collected to yield 85.5 g of ethyl 3-amino-3-ethoxyacrylate, nD25 = 1.4808. The ir and nmr spectra were consistent with the assigned structure.

1. customIn an oven-dried flask were placed
2. temperatureThe solution was cooled to 0°
3. customthe flask was sealed
4. customThe mixture was refrigerated for several days until precipitation of white solid
5. filtrationThe white precipitate was collected by filtration
6. additionThe ether-suspension was mixed with 1000 ml of a 40% aqueous solution of potassium carbonate (
7. temperaturepreviously cooled to 0°)
8. customThe ether layer was separated
9. washThe aqueous phase was washed three times with 150 ml portions of diethyl ether
10. additionThe washings were added to the ether phase over potassium carbonate
11. customThe combined ether phase and washings were decanted onto approximately 80 g of fresh anhydrous potassium carbonate
12. customThe potassium carbonate was removed by filtration
13. customthe ether was removed by evaporation under reduced pressure
14. distillationThe residue was distilled at 0.25 mm
15. distillationThe fraction distilling at 60°
16. customwas collected

ORD record

ord-2200b21d4d9a48c7a2cc4ba128086db0

Source dataset

uspto-grants-1977_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04059433