A study of the synthesis of 2-trifluoromethyl pyrimidines.

Abstract

iPhenylbutanedione-1,3 and 2,4-pentanedione were reacted with trifluoroacetamidine in the presence of sodium ethoxide. A crystalline product melting at 38.4°C was recovered from the reaction of 2 ,4-pentanedione and trifluoroacetamidine and tentatively identified by its infrared spectra as 2-trifluoromethyl-4-,6-dimethylpyrimidine<> The reaction of trifluoroacetamidine and phenylbutanedione-1, 3 in the presence of sodium ethoxide yielded a white crystalline product melting at 90.3°C which was also tentatively identified as the 2-trifluoromethyl-4-methyl- 6-phenylpyrimidine. The amidine of trifluoroacetic acid reacted in a manner described for the reaction of an amidine with a beta-diketone. Yields obtained (19-34%) were within the limits reported for many other pyrimidine syntheses, influenced in part by the instability of trifluoroacetamidine.