Potassium Hydroxide → HCID 19741658, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 19 g (mmol) 3'-allyl-2'-hydroxyacetophenone, 25 g (110 mmol) pentafluorobenzoyl chloride, 36 g (110 mmol) tetra-n-butylammonium bisulfate, 750 ml 10% aqueous KOH, and 750 ml benzene was heated at 80° C. for 6 hours, cooled and the phases separated. The organic phase was concentrated in vacuo and flash chromatographed over 100 g silica gel with success, 2 liter portions of hexane, diethyl ether and CHCl3. The diethyl ether eluate was evaporated in vacuo. The residue was dissolved in 250 ml methanol and cooled at -20° C. for 24 hours. The mixture was filtered and yielded 8-allyl-2-(pentafluorophenyl)-4H-benzopyran-4-one as 10.141 g (27%) solid: TLC Rf 0.35 in 49:25:25:1 CHCl3 :toluene:hexane:methanol.

Provenance & Evidence