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, 3H, CH3), 1.90 (s, 3H, 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-422ae5a3da584a2fa4ececbff32f38d1

Source dataset

uspto-grants-2011_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07875602B2