Sodium Hydroxide → 3-Methyl-5-phenyl-2,4-pentadienoic acid

Participants

Reaction Steps

To a stirred solution of 3-methyl-5-phenyl-2,4-pentadienal (16.5 g) in ethanol (330 mL) was added dropwise a solution of silver nitrate (19.28 g) in water (160 mL) followed by dropwise addition of an aqueous sodium hydroxide (25 g, 80 mL) solution. The resulting mixture was allowed to stir for an additional five hours and then filtered. The solid was washed with ethanol. The combined filtrate was concentrated in vacuum. The residue was dissolved in water (200 mL). The aqueous solution was extracted with ether (300 mL) twice and acidified with 6 N hydrochloric acid (74 mL). The solid formed was filtered and recrystallized from methanol (40 mL) to yield 2.65 g of the desired 3-methyl-5-phenyl-2,4-pentadienoic acid. 1H NMR (acetone-d6, 300 MHz), δ(ppm) 7.60 (d, 2H), 7.35 (m, 3H), 7.06 (m, 2H), 6.02 (broad s, 1H), 2.50 (s, 3H).

Provenance & Evidence