4-Hydroxybenzaldehyde → 3-[4-(4-Hydroxybutoxy)phenyl]prop-2-enoic acid

Temperatur

120 °C

In a 1 L three neck distillation flask, p-hydroxybenzaldehyde (40.0 g, 328 mmol), 4-chlorobutylacetate (54.3 g, 360 mmol), potassium carbonate (45.3 g, 32.8 mmol) and dimethylformamido (150 ml) were placed and stirred for 3 hours at 120° C. After the reaction mixture was cooled, water was added and the resulting mixture was extracted with ethyl acetate. The solvent was removed to obtain an oily product. To the product, malonic acid (40.8 g, 392 mmol), pyrrolidine (10 ml) and pyridine (200 ml) were added and stirred for 2 hours at 120° C. The mixture was cooled to 60° C., and methanol (200 ml) and 40 wt. % potassium hydroxide aqueous solution (200 ml) were added and stirred for 2 hours at 60° C. The mixture was cooled, and then poured into a dilute hydrochloric acid (prepared by diluting 330 ml of concentrated hydrochloric acid with 4 L water) The deposited crystalline product was collected by filtration, and recrystallized from acetonitrile to obtain the titled compounds (65.6 g, yield: 85%).

1. temperatureAfter the reaction mixture was cooled
2. extractionthe resulting mixture was extracted with ethyl acetate
3. customThe solvent was removed
4. customto obtain an oily product
5. stirringstirred for 2 hours at 120° C
6. temperatureThe mixture was cooled to 60° C.
7. stirringstirred for 2 hours at 60° C
8. temperatureThe mixture was cooled
9. filtrationwas collected by filtration
10. customrecrystallized from acetonitrile

ORD-Eintrag

ord-aa34bda9d4f542848909d8a21718401e

Quelldatensatz

uspto-grants-2002_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06461694B1