Divergent and chemoselective deuteration of -unsubstituted imidazoles enabled by precise acid/base control.

Herein, we report acid/base-controlled and divergent deuteration of -unsubstituted imidazoles in an imidazole-selective manner. This protocol enabled the deuteration of not only the 4-arylimidazoles but also the 2-arylimidazoles without labelling the aromatic rings. We demonstrated the advantages of this protocol by the synthesis of deuterated pharmaceuticals, which is difficult to achieve by means of transition metals.