Carbon monoxide enabling synergistic carbonylation and (hetero)aryl migration

The activation and transformation of carbon monoxide (CO), a versatile C1 feedstock, continues to attract substantial attention. Traditionally, researchers have focused on the development of catalytic systems to activate CO and then quench the generated acyl intermediate with nucleophiles to complete the carbonylative transformations. Here, non-classically, we unveil a visible-light-induced, carbonylation-triggered radical relay rearrangement reaction, in which the CO insertion step is a key element for functional group migration. The selective insertion of a carbonyl group into the newly generated carbon radical provides a bridge for (hetero)aryl group migration, and the positive feedback of group migration also enables the carbon radical to capture CO more efficiently. A series of 1,4-dicarbonyl compounds containing fluoroalkyl and heterocycles are synthesized successfully under mild conditions, and the conversion of the products to valuable heteroaromatic biaryls indicates the synthetic potential of this platform. The activation and transformation of carbon monoxide (CO) continues to attract much attention. Now, the authors report a visible-light-induced, carbonylation-triggered radical relay rearrangement reaction in which the CO insertion step enables (hetero)aryl group migration.