Overcoming conformational strain in directed C3-C( sp 3 )–H activation for saturated azacycles (opens in new tab)

Functionalization of saturated azacycles through Pd-catalysed C3-C(sp3)–H activation leveraging the endocyclic nitrogen as a directing group has been hindered by the intrinsic geometric strain of the palladacycle intermediate. Now, an amine N-oxide strategy overcomes this issue by forming a favourable five-membered palladacycle transition state, enabling selective C3 arylation.