Heterocyclic polyfluoro-compounds. Part XI. Synthesis and some reactions of 2,3,5,6-tetrafluoropyridine-4-aldehyde and -4-nitrile
Abstract
Ozonolysis of 2,3,5,6-tetrafluoro-4-propenylpyridine or reduction of 2,3,5,6-tetrafluoropyridine-4-nitrile with Raney alloy–aqueous formic acid yields 2,3,5,6-tetrafluoropyridine-4-aldehyde, several derivatives of which have been prepared. Tetrafluoropyridine-4-nitrile can be obtained by treatment of pentafluoropyridine with sodium cyanide in dimethylformamide or by reaction of tetrachloropyridine-4-nitrile with anhydrous potassium fluoride. Ozonolysis of 2,3,5-trifluoro-4-methyl-6-propenylpyridine provides 3,5,6-trifluoro-4-methylpyridine-2-aldehyde. Tetrafluoroisonicotinamide has been prepared.