Hydrochloric Acid → 2-[[(1-Methylethylidene)amino]oxy]propanoic acid

The ethyl α-(isopropylideneaminooxy)propionate was added to 5% NaOH solution (1.2 L) at 70° C. After 20 min, the solution was cooled to rt and acidified to pH 2.0 with 5N HCl solution. Then to the solution was added (NH4)2SO4 (500 g) and the mixture was extracted with 1:1 benzene:Et2O (2×300 mL). The combined organic extracts were dried over Na2SO4 and concentrated to approximately 200 mL. Petroleum ether (500 mL) was added and the solution was cooled to −20° C. overnight. The recrystallized product was recovered by filtration. 80 g of product 2 was recovered as a white solid (37%). 1H NMR (CDCl3): δ 4.64 (q, 1H, J=6.9 Hz, CH), 1.93 (s, 3 H, CH3), 1.90 (s, 3 H, CH3), 1.50 (d, 3H, J=6.9 Hz, CH3); M.p. 59-61° C.

1. extractionthe mixture was extracted with 1:1 benzene
2. dry with materialThe combined organic extracts were dried over Na2SO4
3. concentrationconcentrated to approximately 200 mL
4. additionPetroleum ether (500 mL) was added
5. temperaturethe solution was cooled to −20° C. overnight
6. filtrationThe recrystallized product was recovered by filtration
7. custom80 g of product 2 was recovered as a white solid (37%)

ORD record

ord-ff02d64860734e26aab2414b55b6e509

Source dataset

uspto-grants-2014_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08779138B2