Unmasked Primary Amines as C-Nucleophiles for Catalytic C–C Bond-Formation

A practical, catalytic entry to α,α,α‑trisubstituted (α‑tertiary) primary amines by C–H functionalisation has long been recognised as a critical gap in the synthetic toolbox. We report a simple and scalable solution to this problem that does not require any in situ protection of the amino group and proceeds with 100% atom-economy. Our strategy, which uses an organic photocatalyst in combination with azide ion as a hydrogen atom transfer (HAT) catalyst, provides a direct synthesis of C -alkylated amines or γ‑lactams, including valuable azaspirocycles. We anticipate that this methodology will inspire new retrosynthetic disconnections for substituted amine derivatives in organic synthesis, and particularly for challenging α‑tertiary primary amines.