Switchable Access to Mono‐ and Di‐Alkylated Boranes via Visible‐Light‐Induced Hydroboration of Alkenes with NHC‐Borane

Abstract A photo‐induced metal‐free radical hydroboration of various styrenes with NHC‐borane has been developed, which can provide mono‐ and di‐alkylated boranes in a selective manner. Besides, this strategy can also be applied to prepare di‐functionalized boranes with two different alkyl groups. Mild reaction conditions and good functional groups compatibility were observed. Preliminary mechanism for this reaction was proposed.