We describe a novel transition metal-free method for the synthesis of N-difluoromethylated pyridines and 4-pyridones/quinolones by using readily available ethyl bromodifluoroacetate as a fluorine source. The formation of N-difluoromethylated pyridines involves a two-step process in which N-alkylation by ethyl bromodifluoroacetate is followed by in situ hydrolysis of the ester and decarboxylation. Besides optimizing the N-difluoromethylation conditions and assessing the influence of steric and electronic effects on the outcome of the reaction, we have synthesized the N-difluoromethylated analogues of two fluorophores and demonstrated that their spectroscopic properties can be improved through replacement of N-CH3 group by N-CF2H.
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