Direct alpha-amination of carbonyl compounds remains an important yet synthetically challenging transformation. Here we report a solution for direct alpha-amination of amides and lactams, identified through fundamental exploration of (3+2) vinyl azide-enolate cycloaddition chemistry. Initial cycloadducts undergo rearrangement via 1,2-N-migration to afford imine intermediates that are readily converted to the target alpha-amino amides or lactams. The sequence requires no pre-functionalisation, can be performed on a range of substrates, including compound classes unsuccessful using reported methods, and delivers primary or secondary alpha-amines. This work highlights the diversity and synthetic potential of the rapidly expanding (3+2) azide-enolate cycloaddition manifold.

Viral infections are one of the leading causes of acute morbidity in humans and much endeavour has been made by the synthetic community for the development of drugs to treat...

Direct alpha-amination of carbonyl compounds remains an important yet synthetically challenging transformation. Here we report a solution for direct alpha-amination of amides and lactams, identified through fundamental exploration of (3+2) vinyl azide-enolate cycloaddition chemistry. Initial cycloadducts undergo rearrangement via 1,2-N-migration to afford imine intermediates that are readily converted to the target alpha-amino amides or lactams. The sequence requires no pre-functionalisation, can be performed on a range of substrates, including compound classes unsuccessful using reported methods, and delivers primary or secondary alpha-amines. This work highlights the diversity and synthetic potential of the rapidly expanding (3+2) azide-enolate cycloaddition manifold.

Vinyl azides have undergone a recent renaissance as versatile synthetic reagents, however their reactivity as 1,3-dipoles in (3+2) cycloadditions remains underexplored. Here the synthesis of ene--lactam scaffolds via (3+2) cycloaddition of -substituted vinyl azides with ester enolates is established. Mechanistic investigations, including isolation of reaction intermediates and density functional theory calculations, implicate an unprecedented conjugatetype addition to the exocyclic alkene of an N-vinyl triazolinone intermediate generated in the cycloaddition step. Determination of the reaction scope and application to synthesis of the natural product sargassumlactam is reported.