Polyfluoro-heterocyclic compounds. Part VI. Nucleophilic substitution in tetrafluoro-4-nitropyridine
作者:R. D. Chambers、J. Hutchinson、W. K. R. Musgrave
DOI:10.1039/j39660000220
日期:——
5,6-tetrafluoro-4-nitrobenzene which gives exclusive replacement of fluorine ortho to the nitro-group. The pyridine-ring nitrogen is the greatest single factor in determining the orientation of nucleophilic attack. Competition experiments show relative reactivities to be in the order: pentafluoropyridine ≈ pentafluoronitrobenzene > tetrafluoro-4-nitropyridine. Fluorine-19 n.m.r. spectra of derivatives