An anti-tetraamination of a 1,3-diene unit via cascade annulations of the azulenone scaffold with dicarbonyl azo-compounds.

Dense and stereo-controlled integrations of C-N bonds on the azulenone scaffold are achieved by sequential (i) ene, (ii) [6 + 2]-cycloaddition, and (iii) hetero-conjugate addition reactions leading to a topologically complex bis-bridged skeleton.