Hypervalent Fluoroiodane‐Triggered Synthesis of Fluoro‐Azabenzoxazepines and Azaindoles

Abstract

Fluorination reactions facilitated by hypervalent F‐iodanes have experienced vivid attention recently, since they often lead to novel, fluorinated scaffolds not accessible with common electrophilic fluorination reagents. The fluorocyclization of styrenes equipped with an amide functionality in the ortho position using F‐iodanes represents a transformation with unusual chemoselectivity. Within this context, the conversion of pyridine derivatives to fluoropyridyloxazepines, which constitutes a particular challenge due to the deactivating properties of the aza heterocycle, was accomplished in this work using the bench‐stable λ3‐F‐benzoiodoxole under Lewis acid catalysis. The versatility of the obtained F‐heterocycles as building blocks in organic synthesis was demonstrated by their straightforward conversion into azaindoles in a one‐pot, three‐step reaction sequence.