Synthesis of Phenanthrene‐Based Polycycles by Gold(I)‐Catalyzed Cyclization of Biphenyl‐Embedded Trienynes

Abstract

Gold(I)‐catalyzed cyclization of o‐alkenyl‐o’‐alkynylbiaryls in the presence of external or internal nucleophiles provides a straightforward access to phenanthrene‐based polycycles, which are of considerable interest in materials science. Thus, their reactions with alcohols yield functionalized dihydrophenanthrenes, in a process that can also be carried out intramolecularly, to provide phenanthrene‐derived heteropolycyclic compounds. Moreover, benzo[b]triphenylenes can be synthesized from o‐methoxyvinyl‐o’‐alkynylbiaryls, in a reaction in which an (hetero)aryl substituent at the triple bond acts as an internal nucleophile.

Total Synthesis of Laetevirenol A via Regioselective Gold‐Catalyzed and Acid‐Promoted Cyclizations

“…Moreover, further functionalization can be achieved if the gold‐catalyzed reaction is performed in the presence of a nucleophile able to react with carbocation I [10] . In this way, alkoxy‐substituted dihydrophenanthrenes 5 are obtained if alcohols are added to the reaction media, and benzo[ b ]triphenylenes 6 are synthesized from o ‐methoxyvinyl‐ o ’‐alkynylbiaryls bearing at the triple bond aryl substituents that act as internal nucleophiles.…”