Photoinduced successive oxidative ring-opening and borylation of indolizines with NHC-boranes.

A facile photoinduced successive oxidative ring-opening and borylation of indolizines with NHC-boranes via a one-pot method has been unveiled. This photo-promoted strategy enables the formation of unsaturated NHC-boryl carboxylates under transition metal-free and radical initiator-free conditions. A wide array of pyridine-containing NHC-boryl carboxylates were directly prepared in moderate to good yields. This work contributes to a better understanding of the reactivity and photo-behavior of both indolizines and NHC-boranes.