Bobbio, CarlaRausis, ThierrySchlosser, Manfred2006-03-032006-03-032006-03-03200510.1002/chem.200400837https://infoscience.epfl.ch/handle/20.500.14299/227042WOS:0002276629000226442Starting from six industrially available fluorinated pyridines, an expedient access to all three tetrafluoropyridines, all six trifluoropyridines, and the five non-com. difluoropyridines was developed. The methods employed for the selective removal of fluorine from polyfluoropyridines were the redn. by metals or complex hydrides and the site-selective replacement by hydrazine followed by dehydrogenation-dediazotation or dehydrochlorination-dediazotation. To introduce an extra fluorine atom, a suitable precursor was metalated and chlorinated before being subjected to a chlorine/fluorine displacement process. [on SciFinder (R)]Diazotization (dediazotization; removal of fluorine from polyfluoropyridines via redn. by metals or complex hydrides and site-selective replacement by hydrazine followed by dehydrogenation-dediazotation or dehydrochlorination-dediazotation); Dehalogenatnucleophilic substitution polyhalopyridine; pyridine halo fluorination defluorinationtext::journal::journal article::research article