Microwave-assisted nucleophilic fluorination: a facile approach to the synthesis of 6′,6′-gem-difluorinated carbocyclic nucleosides

Nucleophilic fluorination of a sterically hindered cyclopentanone intermediate under microwave irradiation is established to construct the key 6′,6′- gem -difluorocarbocyclic scaffold, which provides a practical approach to the synthesis of 6′,6′- gem -difluorinated carbocyclic nucleosides. The requisite cyclopentanone was accessed through the optimized oxidative cleavage of a methylenecyclopentane precursor derived from an intramolecular radical cyclization. This concise strategy shortens the synthetic steps and enables the expansion of nucleobase diversity for 6′,6′- gem -difluorinated carbocyclic nucleosides.