反应详情

Commercially available 4-fluorobenzaldehyde of formula V-1 is condensed with acetone, under basic conditions, to provide 1,5-Bis-(4-fluorophenyl)-penta-1,4-dien-3-one of formula V-2. The dienone is reduced with magnesium in methanol to provide the ketone of formula V-3. The ketone of formula V-3 is converted to dihydropyrone products of formula V-8 using chemistry analogous to that described in Chart U for the sequence of reactions from U-3 to U-8.