Photochemistry of ortho-Azidocinnamoyl Derivatives: Facile and Modular Synthesis of 2-Acylated Indoles and 2-Substituted Quinolines under Solvent Control

The light-promoted potential of ortho-azidocinnamoyl compounds is evaluated for heterocycle synthesis. Depending on the nature of the solvent, 2-acylated indoles were obtained under aprotic conditions, whereas the use of a protic medium led to 2-substituted quinolines. The synthetic significance of this metal-free method is that, by simply changing the solvent, the reaction outcome can be directed towards different key heterocyclic scaffolds.