Facile preparation of 3-substituted-2,6-difluoropyridines: application to the synthesis of 2,3,6-trisubstituted pyridines

摘要

We report a facile method for the difluorination of 3-substituted-2,6-dichloropyridines using cesium fluoride as a fluorination reagent in dimethyl sulfoxide. It is proposed that this method for preparing 3-substituted-2,6-difluoropyridines is simpler and easier than those reported in previous literature. To examine the utility of 3-substituted-2,6-difluoropyridines in synthetic chemistry, we also demonstrate a subsequent conversion to 2,3,6-trisubstituted pyridines by a tandem nucleophilic aromatic substitution. (C) 2015 Elsevier Ltd. All rights reserved.