Photoinitiated Rearrangement of Aromatic Azides to 2-Aminonicotinates.

This study describes a one-pot photoinduced method for azepine synthesis and their subsequent rearrangement into pyridines. The rearrangement of the azepine, formed during photolysis, occurs due to both thermal and photochemical activation of the reaction. This requires an electron-donating substituent at the second position of the azepine and an electron-withdrawing substituent at the third position of the azepine. A reaction mechanism has been proposed to explain the role of water and the nature of the azepine substituents.