HETEROCYCLIC POLYFLUORO-COMPOUNDS .23. REACTION OF SOME 2-, 3-, AND 4-SUBSTITUTED PYRIDINE 1-OXIDES, 5-METHYLPYRIMIDINE 1-OXIDE, AND QUINOLINE 1-OXIDE WITH PERFLUOROPROPENE, AND OF PYRIDINE 1-OXIDE WITH PERFLUORO-(2-METHYLPENT-2-ENE) - SYNTHESIS OF 2-(1,2,2,2-TETRAFLUOROETHYL)-PYRIDINES OR 2-(1,2,2,2-TETRAFLUOROETHYL)-PYRIMIDINES AND THEIR N-OXIDES AND OF 2,2,3-TRIFLUORO-2,3-DIHYDRO-3-TRIFLUOROMETHYLFURO[3,2-B]PYRIDIN-

Perfluoropropene reacts thermally with 2-chloro-, 2-cyano-, and 2-(1,2,2,2-tetrafluoroethyl)-pyridine [a plant growth regulator] 1-oxide and with 4-methyl-, 4-methoxy-, and 4-nitro-pyridine 1-oxide to yield carbonyl fluoride and the corresponding 2- or 4-substituted 6-(1,2,2,2-tetrafluoroethyl)pyridines. Thermal deoxygenation of 3-bromo-, 3-chloro-, or 3-fluoro-pyridine 1-oxide with perfluoropropene yields a mixture of the corresponding 3- and 5-halogeno-2-(1,2,2,2-tetrafluoroethyl)pyridines plus 2,2,3-trifluoro-2,3-dihydro-3-trifluoromethylfuro[3,2-.beta.]pyridine and, in the cases of 3-bromo- and 3-chloro-pyridine 1-oxide, 3- and 5-fluoro-2-(1,2,2,2-tetrafluoroethyl)pyridine. Oxidation of the 2-(1,2,2,2-tetrafluoroethyl)pyridines 2-(CF3.cntdot.CHF)C5H3NX (X = H, 3-Br, 3-Cl, 3-F, 4-Me, 4-NO2, 5-Br, 6-Cl, 6-CN, or 6-Me) with peroxy-acid yields the corresponding 1-oxides: 2,2,3-trifluoro-2,3-dihydro-3-trifluoromethylfuro[3,2-.beta.]pyridine 4-oxide can be prepared similarly. Deoxygenation of pyridine 1-oxide with perfluoro-(2-methylpent-2-ene) yields 2-(2H-hexafluoroisopropyl)pyridine. Reaction of 5-methylpyrimidin 1-oxide with perfluoropropene yields 5-methyl-4- and 5-methyl-2-(1,2,2,2-tetrafluoroethyl)pyrimidine; oxidation of the former with peroxy-acid gives predominantly 5-methyl-4-(1,2,2,2-tetrafluoroethyl)pyrimidine 1-oxide.