Reaction of 3-isothiocyanato-2-propeniminium perchlorates 1 with hydro
xylamine gives 1-hydroxy-2(1H)-pyrimidine-2-thiones 2 which can be O-a
cylated. The resulting 1-acyloxy-2(1H)-pyrimidine-2-thiones 4 are nove
l precursors for organic radicals. Their photochemical homolysis is st
udied and affords disulfides 5, 2-alkylthiopyrimidines 6 and alkanes 7
and 8.