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

Participants

Reaction Conditions

Reaction Steps

Following the procedure of Example 1, para-bromophenol (43.25 grams), acrylic acid (27 grams) and phenothiazine (0.02 grams) were added to the pressure reactor. The system was closed and evacuated before being cooled to -78° C. and the anhydrous hydrogen fluoride (110 grams) was added. After the mixture was heated and stirred for six hours at 100° C., 140 psig, the excess hydrogen fluoride was vented and the reaction mixture cooled to 0°-5° C. After washing the mixture with D.I. water, HPLC analysis indicated one major product which was separated and characterized as 6-Bromo-4-Chromanone.

Provenance & Evidence