Photocatalyst‐free, Visible Light Driven, Gold Promoted Suzuki Synthesis of (Hetero)biaryls

A visible‐light driven Suzuki cross‐coupling reaction was performed with colored and bench‐stable arylazosulfones in the presence of Ph3PAuCl (5 mol %) as the catalyst. The absence of a photocatalyst, along with the use of commercially available and easy‐to‐handle arylboronic acids underline the novelty and synthetic usefulness of the protocol. A reaction mechanism involving the generation of an aryl radical as the key intermediate has been proposed on the basis of experimental investigations. So free, so good. A version of Suzuki cross‐coupling is realized by merging visible photoredox catalysis and [AuI] catalysis. The employment of colored and photolabile arylazosulfone as reaction partners enables the biaryl forming protocol to be performed under photocatalyst‐free conditions.