Hydrochloric Acid → HCID 86713144, compound

Participants

Reaction Steps

In a round-bottom flask, ethyl (2E)-5-(1-hydroxy-2,6,6-trimethyl-4-oxocyclohex-2-en-1-yl)-3-(trifluoromethyl)pent-2-en-4-ynoate (130 mg, 0.38 mmol) was dissolved in a mixture of water and tetrahydrofuran, and sodium hydroxide (38 mg, 0.94 mmol) was then added. The resulting reaction mixture was stirred under reflux for 2 h and, after cooling to room temperature, acidified with aqueous hydrochloric acid. The aqueous phase was repeatedly extracted thoroughly with dichloromethane, and the combined organic phases were then dried over magnesium sulfate, filtered and concentrated under reduced pressure. By final column chromatography purification of the resulting crude product (ethyl acetate/heptane gradient), (2E)-5-(1-hydroxy-2,6,6-trimethyl-4-oxocyclohex-2-en-1-yl)-3-(trifluoromethyl)pent-2-en-4-ynoic acid (40 mg, 32% of theory) was obtained in the form of a colorless solid. 1H-NMR (400 MHz, CDCl3 δ, ppm) 10.14 (br. s, 1H, OH), 6.70 (s, 1H), 5.92 (s, 1H), 2.61 (d, 1H), 2.43 (d, 1H), 2.30 (br. s, 1H, OH), 2.16 (s, 3H), 1.28 (s, 3H), 1.13 (s, 3H).

Provenance & Evidence