Photo- or Electrochemical Cyclization of Dienes with Diselenides to Access Seleno-Benzo[ b ]azepines.

A cascade selenylation/cyclization of dienes with diselenides has been realized under visible-light irradiation or electrolysis conditions. Employing O 2 or electricity as a "green" oxidant, this protocol provides a green and efficient method for an array of biologically important seleno-benzo[ b ]azepine derivatives in moderate to good yields. The direct sunlight irradiation and gram-scale reaction render the approach practical and attractive.