Acetaldehyde → HCID 53757217, compound

The precursor nitroalcohol compound 3-methyl-3-nitro-2-butanol can be prepared as follows: 88.10 grams of acetaldehyde mixed with 88.10 grams of ethanol (previously cooled in refrigerator) was added dropwise to 178.2 grams of 2-nitropropane in 100 ml of ethanol and 4 ml of NaOH. After about two-thirds of this acetaldehyde-ethanol addition charge was added, 4 ml of 10N NaOH and 15 ml of H2O were added to the reaction mixture. The remaining addition charge was then added dropwise to the reaction mixture as before. After being stirred one hour at room temperature, the reaction contents were transferred to a two liter distilling flask with magnetic stirring and c.w. condenser. A heating mantle was used, and the temperature adjusted to 35° C. At the end of a two-day period, the temperature had reached 39° C., and the heating mantle was shut off. Stirring of the reaction mixture continued. At the end of another two-day period, the temperature had fallen to 24° C. The pH of the reaction mixture was adjusted to 6.7 with 21 ml of a 9 gram 37% HCl in 68 ml H2O solution. The next day, the pH was found to still be at 6.7. Vacuum distillation with a hot water bath, vigoro tube, c.w. condenser, ice-chilled receiver, and dry ice trap was then begun. Heads came off from 50 mm pressure and 25° C. (pot temperature) through 3 mm pressure and 40° C. (pot temperature). The solution had turned blue-green, but nearly all of the color was removed with the heads in a first removed fraction of 265 ml. A second fraction of 27.53 grams was removed with a pot temperature of 66° C., a head temperature of 48° C., and 2 mm pressure. A third fraction of 86.11 grams of a slightly viscous liquid was removed at a pot temperature of 69° C., a head temperature of 55°-58° C., and 2 mm pressure. The second and third fractions were combined and found to be 85-86% pure 3-nitro-3-methyl-2-butanol by gas chromatography.

1. temperaturepreviously cooled in refrigerator)
2. additioncharge
3. additionwas added
4. additionThe remaining addition
5. additioncharge
6. additionwas then added dropwise to the reaction mixture as before
7. customthe reaction contents
8. distillationdistilling flask
9. stirringwith magnetic stirring
10. customadjusted to 35° C
11. customhad reached 39° C.
12. stirringStirring of the reaction mixture
13. customhad fallen to 24° C
14. distillationVacuum distillation with a hot water bath, vigoro tube
15. temperaturecondenser, ice-chilled receiver, and dry ice trap
16. customcame off from 50 mm pressure and 25° C. (pot temperature) through 3 mm pressure and 40° C. (pot temperature)
17. customnearly all of the color was removed with the heads in a first removed fraction of 265 ml
18. customA second fraction of 27.53 grams was removed with a pot temperature of 66° C.
19. customa head temperature of 48° C., and 2 mm pressure
20. customA third fraction of 86.11 grams of a slightly viscous liquid was removed at a pot temperature of 69° C.
21. customa head temperature of 55°-58° C., and 2 mm pressure

ORD record

ord-fdfa15f840984d87b3ac1306f9483a3d

Source dataset

uspto-grants-1985_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04549883