Synthesis of selenium‐containing biindolyls and their Diels–Alder reaction toward the synthesis of heteroannulated [a]‐ and [c]‐carbazoles

We reported the first syntheses of 2‐ and 3‐(2‐(benzo[b]selenophen‐2‐yl)‐indoles and their Diels–Alder reactions to furnish six unique annulated benzoselenphene carbazoles. This facile route can be used to synthesize selenium‐containing biindolyl derivatives that possessed potential pharmaceutical activities. This was a study of Diels–Alder reaction of selenium‐containing biindolyls with two dienophiles to yield six new carbazoles.