Methane → 7-Fluoro-4-hydroxy-2H-1-benzopyran-2-one

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-fluorophenol (31.5 g, 0.281 mol), malonic acid (29.24 g, 0.281 g) and zinc chloride (100.0 g, 0.734 mol) in phosphorus oxychloride (70 mL, 0.751 mol) is heated at 65° C. overnight and poured into an ice/water mixture. The resultant aqueous mixture is filtered to obtain a pale green solid. A mixture of the solid in 10% sodium hydrogen carbonate solution is stirred at room temperature for 2 hours, decolorized with charcoal and filtered through diatomaceous earth. The filtrate is acidified with concentrated hydrochloric acid and the resultant precipitate is collected and dried to give the title product as a brown solid, mp 229°-230° C.

Provenance & Evidence