Metal- and CO-Free Carbonylation of Alkyl Iodides

We report a new method for the carbonylation of alkyl iodides under photochemical conditions. The process relies on a simple aryl formate reagent, synthesized in one step from readily available chemicals and capable of releasing CO along with a phenolate species in the presence of a mild base. The photoactivity of this phenolate is harnessed to activate alkyl iodides via single-electron transfer and generate alkyl radicals that add to CO and ultimately offer access to carboxylic acids and amides. This new, user-friendly procedure overcomes the typical need for CO gas and/or metal catalysts in carbonylation chemistry while being highly efficient and versatile to accommodate a variety of functional groups.