Heck-type 5-endo-trig cyclization promoted by vinylic fluorines: synthesis of 5-fluoro-3H-pyrroles

A 5-endo-trig alkene insertion proceeds under palladium catalysis via aminopalladium species starting from 3,3-difluoro-allyl ketone O-pentafluorobenzoyloximes, providing a facile access to 5-fluoro-3H-pyrroles.