A novel metal- and catalyst-free dearomative reaction of 2-oxypyridines to construct gem -difluoromethylenated N-substituted 2-pyridones has been developed. The reaction involves an attractive acyl rearrangement from O to CF 2 of difluorocarbene-derived pyridinium ylides, which provides a new strategy for the direct introduction of the gem -difluoromethylene group with high efficiency and selectivity as well as broad substrate scope. Gram-scale synthesis and synthetic transformations have also been demonstrated.