Perfluoroepoxyoxolanes in the synthesis of fluorine-containing heterocycles

Perfluoro-3,4-epoxyoxolane and 3,4-epoxy-2-trifluoromethylpentafluorooxolane readily reacted with difunctional nucleophiles via opening of the oxirane ring and subsequent heterocyclization. Their reactions with thiourea and o-phenylenediamine gave new fluorine-containing fused heterocyclic compounds, 2-amino-3a-hydroxy-4,4,6,6,6a-pentafluoro-3a,4,6,6a-tetrahydrofuro[3,4-d][1,3]thiazole and 1,1,3,3-tetrafluoro- and 1-trifluoromethyl-1,3,3-trifluoro-1,3-dihydrofuro[3,4-b]quinoxalines, respectively. The molecular and crystalline structures of the products were determined by X-ray analysis.