Hydrochloric Acid → 2-Acetylamino-6-methyl-6-nitroheptanoic acid

Temperature

90 °C

Diethyl 2-acetylamino-2-(4-methyl-4-nitropentyl)malonate (193.5 g, 558.5 mmol) was dissolved in ethanol (270 ml), and potassium hydroxide (51 g, 781.9 mmol) was dissolved in water (250 ml) and added. The mixture was stirred at 90° C. for 1 h, and potassium hydroxide (51 g, 781.9 mmol) was dissolved in water (250 ml) and added. The mixture was stirred at the same temperature for 2 h. The mixture was cooled to 40° C. and concentrated hydrochloric acid was added to adjust the solution to pH 1.5, which solution was stirred overnight at 80° C. Ethanol was evaporated by concentration under reduced pressure and the residue was ice-cooled. The precipitated crystals were separated, and the obtained slurry was washed with ethyl acetate (200 ml) and dried under reduced pressure to give the objective compound (99.6 g, yield 72%).

1. additionadded
2. additionadded
3. stirringThe mixture was stirred at the same temperature for 2 h
4. temperatureThe mixture was cooled to 40° C.
5. stirringwas stirred overnight at 80° C
6. customEthanol was evaporated by concentration under reduced pressure
7. temperaturecooled
8. customThe precipitated crystals were separated
9. washthe obtained slurry was washed with ethyl acetate (200 ml)
10. customdried under reduced pressure

ORD record

ord-50dda18fc26b4d8a9c83b8a28101897a

Source dataset

uspto-grants-2003_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06664412B2