Hydrochloric Acid → 7-Phenyl-2,4,6-heptatrienoic acid

Temperatur

-65 °C

Butyllithium (12.8 mL of 2.5 N solution) was added to 65 mL of anhydrous tetrahydrofuran (THF) at −65° C. A solution of diethylphosphonoacetic acid (2.92 g) in 25 mL of anhydrous THF was added dropwise to the stirred solution at −65° C. The resulting solution was stirred at −65° C. for an additional 30 minutes and then a solution of 5-phenyl-2,4-pentadienal (2.4 g) in 15 mL of anhydrous THF was added to the reaction at −65° C. The reaction was stirred for one hour, allowed to warm to room temperature and then stirred overnight. To the reaction was added 30 mL of water, acidified with 5% hydrochloric acid (14 mL) to a pH of 4.7 and then added an additional 20 mL of water. The aqueous layer was extracted with 10 mL of ether twice and with 10 mL of ethyl acetate once. The combined organic extract was dried over anhydrous sodium sulfate, filtered and concentrated under vacuum. The crude material was dissolved in 50 mL of hot methanol and then refrigerated overnight. The crystals formed were filtered and dried under vacuum to afford 2.4 g of the desired 7-phenyl-2,4,6-heptatrienoic acid. 1H NMR (DMSO-d6, 300 MHz), δ (ppm) 7.52 (m, 2H), 7.33 (m, 4H), 7.06 (m, 1H), 6.86 (m, 2H), 6.58 (m, 1H), 5.95 (d, 1H).

1. stirringThe reaction was stirred for one hour
2. temperatureto warm to room temperature
3. stirringstirred overnight
4. extractionThe aqueous layer was extracted with 10 mL of ether twice
5. extractionThe combined organic extract
6. dry with materialwas dried over anhydrous sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated under vacuum
9. dissolutionThe crude material was dissolved in 50 mL of hot methanol
10. customrefrigerated overnight
11. customThe crystals formed
12. filtrationwere filtered
13. customdried under vacuum

ORD-Eintrag

ord-239f77417ef44848a50b0206e5a90cfc

Quelldatensatz

uspto-grants-2011_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07902259B2