Ammonia → (2E)-2-Propyl-2-pentenoic acid

1425 g of glycerol are placed in a four liter flask. 470 g of KOH are added and the mixture is slowly heated, the potassium hydroxide dissolving at approximately 100° C. After reaching a temperature of 140° C., over a period of 11/2 hours 264.4 g of 2-propyl-2-pentene nitrile are added dropwise, the temperature being kept at 140° to 145° C. Slight foaming initially occurs. The reaction mixture is refluxed for 8 hours, accompanied by the escape of ammonia and followed by mixing with 1700 ml of water. After cooling a roughly 2 cm thick, flaky foam layer has deposited on the clear yellow solution. The reaction mixture is acidified to pH 1 with 620 ml of concentrated hydrochloric acid. The separated oil is then taken up with 100 ml of n-hexane and the aqueous phase is again extracted twice with in each case 400 ml of n-hexane. After washing the organic phase with water and drying, a residue of 260 g is obtained by evaporating at 80 mbar and 40° C. Through precision distillation on an active column, 145.4 g of E-2-propyl-2-pentenoic acid is obtained therefrom corresponding to 50.4% of theory. The b.p.15 is 135° to 136° C. The distillate solidifies to a crystalline mass with a melting point of 38° C.

1. temperaturethe mixture is slowly heated
2. customat approximately 100° C
3. customa temperature of 140° C.
4. custombeing kept at 140° to 145° C
5. temperatureThe reaction mixture is refluxed for 8 hours
6. temperatureAfter cooling a roughly 2 cm thick
7. extractionthe aqueous phase is again extracted twice with in each case 400 ml of n-hexane
8. washAfter washing the organic phase with water
9. customdrying
10. customa residue of 260 g is obtained
11. customby evaporating at 80 mbar and 40° C
12. distillationThrough precision distillation on an active column

ORD record

ord-8cd64cf7c44041f998bb8a0a127ac43d

Source dataset

uspto-grants-1990_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04945180