Hydrogen Bromide → Trimethylpyruvic acid amide

111.0 g (1 mole) of pivaloyl cyanide were added dropwise to 800 g of a 36% strength solution of hydrogen bromide in glacial acetic acid at room temperature, while stirring. When the addition had ended, the mixture was subsequently stirred at room temperature for 3 hours. 9 ml (0.5 mole) of water were then added dropwise at 20° to 25° C. and the mixture was subsequently stirred at room temperature for 1 hour. The reaction solution was then poured into an excess of saturated sodium bicarbonate solution. It was extracted three times with 200 ml of methylene chloride each time. The combined organic phases were washed with 200 ml of water, dried over sodium sulphate and concentrated by distilling off the solvent in vacuo. After some time, the oil which remained crystallized completely. The recrystallization from petroleum ether gave 113.5 g (88% of theory) of trimethylpyruvic acid amide of melting point 69° to 70° C.

1. additionWhen the addition
2. stirringthe mixture was subsequently stirred at room temperature for 3 hours
3. stirringthe mixture was subsequently stirred at room temperature for 1 hour
4. extractionIt was extracted three times with 200 ml of methylene chloride each time
5. washThe combined organic phases were washed with 200 ml of water
6. dry with materialdried over sodium sulphate
7. concentrationconcentrated
8. distillationby distilling off the solvent in vacuo
9. customAfter some time, the oil which remained crystallized completely
10. customThe recrystallization from petroleum ether

ORD record

ord-7fa60152b4354b23b6a88c6f425158a4

Source dataset

uspto-grants-1982_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04309538