The synthesis of some 7, 7-difluoro-7, 8-dihydropterins and pterins with fluoroalkyl subsitutents at the 6 or 7 positions from fluorine-containing aliphatic precursors and suitably substituted pyrimidines is described. The fluorine-containing pterins were found to be very insoluble and also stable to nucleophiles and bases in dilute aqueous solution.