Sulfuric Acid → HCID 66823716, compound

Participants

Reaction Steps

To an ice-cold solution of crude 2-(4′-chloro-4-trifluoromethylbiphenyl-3-yl)-4,4,6,6-tetramethyl-1,5-dioxaspiro[2.4]heptan-7-one (2.59 g, 6.12 mmoles) in dichloroethane (25 ml) is added concentrated sulfuric acid (5 ml), followed by stirring at this temperature for 2 hours. The reaction mixture is poured into ice, extracted with dichloromethane (×2), and the combined organics are evaporated under reduced pressure to yield a brown gum. Purification by flash column chromatography (isohexane to 30% ethyl acetate in isohexane as eluant) then reverse phase preparative HPLC affords 4-(4′-chloro-4-trifluoromethylbiphenyl-3-yl)-2,2,6,6-tetramethylpyran-3,5-dione (0.370 g) as a white solid.

Provenance & Evidence