AN IMPROVED METHOD FOR THE PREPARATION OF 3,5-DIFLUOROSALICYLALDEHYDE AND 3,5-DIFLUOROSALICYLIC ACID

Abstract An improved method for the synthesis of 3,5-difluorosalicylic acid (3b) and 3,5-difluorosalicylaldehyde (3a) is described. 2,4-Difluorophenol (4) undergoes a formylation reaction to afford aldehyde 3a which is oxidized to the desired acid 3b. This method avoids the use of the highly corrosive HF and fluorine gas and requires no special laboratory apparatus. #Dedicated to the memory of Rosemarie R. Ungarelli, Academic Advisor, Chemistry Department, Long Island Univeristy, C.W. Post Center.