Metal-Free Catalytic Formylation of Amides Using CO2 under Ambient Conditions

This study reports the metal-free formylation of amides using carbon dioxide under ambient conditions. An abnormal N-heterocyclic carbene (aNHC) acts as an efficient catalyst for the formylation of amides in the presence of hydrosilane at room temperature. This methodology enables the formation of a C–N bond and can be utilized in building up core moieties of two natural products having strong larvicidal activity such as alatamide and lansiumamide A. A preliminary mechanistic picture for this transformation has been proposed through isolation of reaction byproduct (confirmed by single crystal X-ray study) as well as by characterizing intermediates with spectroscopy.