1,2-Diamination of Alkenes via 1,3-Dipolar Cycloaddition with Azidium Ions or Azides

We describe two new methods for the 1,2-diamination of alkenes. First, either an azidium ion (ArN=N+=NAr) undergoes 1,3-dipolar cycloaddition with an alkene to give a 1,2,3-triazolinium ion directly, or an intramolecular azide-alkene cycloaddition followed by N-benzylation provides the same. Second, hydrogenation of the 1,2,3-triazolinium ion over Raney Ni excises the central N atom and gives the 1,2-diamine. The stereochemistry of the alkene is usually, but not always, preserved in the 1,2-diamine.

Automated summary

We present two new methods for the 1,2-diamination of alkenes. The first method involves the 1,3-dipolar cycloaddition of an azidium ion with an alkene, resulting in the formation of a 1,2,3-triazolinium ion. Alternatively, an intramolecular azide-alkene cycloaddition followed by N-benzylation can also yield the same product. The second method involves the hydrogenation of the 1,2,3-triazolinium ion using Raney Ni, which removes the central N atom and gives the 1,2-diamine product. The stereochemistry of the alkene is generally preserved in the 1,2-diamine, although there may be exceptions.