Accessing Sterically Congested Benzannulated Cyclic Aryl Ethers via Photoredox Decarboxylative Giese-Type C2–C3 Bond Formation

Abstract

Abstract The visible-light-driven photocatalytic decarboxylation of α-aryloxy carboxylic acids produces α-oxy carbon-centered radicals that undergo intramolecular Giese addition to form 2,3-dihydrobenzofurans, chromans, 2,3,4,5-tetrahydrobenzo[b]oxepines, and 3,4,5,6-tetrahydro-2H-benzo[b]oxocines. In contrast to the existing methods, this unconventional strategy for the construction of five-, six-, seven-, and eight-membered oxygen heterocycles via the formation of the C2–C3 bond enables the synthesis of sterically demanding O-heterocycles bearing multiple substituents at the C2 and C3 positions. The mild reaction conditions render these transformations highly chemoselective and compatible with various functional groups.

The authors' abstract, as published at the source. The Journal of Organic Chemistry, 2026 · DOI ↗