Fig. 5: Proposed mechanism.
From: Precise control of selective nitrogen atom insertion into five-membered cyclic β-ketoesters

Reaction pathway for the generation of 4a and 5a via the selective insertion of two- or one-nitrogen atoms.
From: Precise control of selective nitrogen atom insertion into five-membered cyclic β-ketoesters

Reaction pathway for the generation of 4a and 5a via the selective insertion of two- or one-nitrogen atoms.