Acrylic Acid → 6-fluoro-2,3-dihydro-4H-1-benzopyran-4-one

Participants

Reaction Conditions

Reaction Steps

Using the procedure established in Example 1, the reactor was charged with p-fluoroanisole (31.5 grams), acrylic acid (27 grams) and phenothiazine (0.02 grams) before being sealed, evacuated, and cooled to -78° C. The anhydrous hydrogen fluoride (110 grams) was vacuum transferred into the reactor and the mixture warmed to 40° C. for one hour then 100° C. for 4.5 hours. The excess hydrogen fluoride was then vented and the reactor cooled to 5° C. before being opened and the contents washed with D.I. water. Analysis by HPLC indicated the presence of para-fluoroanisole and 6-Fluoro-4-Chromanone. The para-fluoroanisole was removed by distillation and the desired 6-Fluoro-4-Chromanone isolated by extraction and characterized.

Provenance & Evidence