Hydrochloric Acid → HCID 85077994, compound

Participants

Reaction Conditions

Reaction Steps

Butyllithium (50 mL of 2.5 N solution) was added to 250 mL of anhydrous tetrahydrofuran (THF) at −65° C. A solution of diethylphosphonoacetic acid (11.4 g) in 90 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 40 minutes and then a solution of α-chloro-cinnamaldehyde (10.0 g) in 60 mL of anhydrous THF was added to the reaction at −65° C. over a period of 95 minutes. The reaction was stirred for one hour, allowed to warm to room temperature and then stirred overnight. The reaction was then acidified with 5% hydrochloric acid (48 mL) to a pH of 3.9. The aqueous layer was extracted with 50 mL of ether twice and with 50 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 30 mL of hot methanol and then refrigerated overnight. The crystals formed were filtered and dried under vacuum to afford 9.2 g of the desired 4-chloro-5-phenyl-2,4-pentadienoic acid. 1H NMR (acetone-d6, 300 MHz), δ (ppm) 7.86 (d, 2H), 7.60 (d, 1H), 7.45 (m, 3H), 7.36 (broad s, 1H), 6.32 (d, 1H).

Provenance & Evidence