Predictable site-selective radical fluorination of tertiary ethers

In this communication, we disclose the first example of metal-free and site-selective radical fluorination of readily available tertiary alkyl ethers, enabled by synergistic photocatalysis and organocatalysis. This catalytic combination allows for exclusive fluorination of tertiary C-O bonds under mild conditions even in the presence of competing reaction sites. The excellent functional group tolerance affords valuable access to sterically hindered alkyl fluorides through late-stage modification of complex molecules. The successful use of tertiary alkyl ethers in radical fluorination enhances the structural diversity of aliphatic fluorides that can be derived from naturally abundant alcohols.