Intramolecular Huisgen‐Type Cyclization of Platinum‐Bound Pyrylium Ions with Alkenes and Subsequent Insertion into a Benzylic CH Bond

Abstract

Access granted: The platinum-catalyzed cyclization of enynals 1, which contain an additional alkene bond in their side chain, through a [3+2] cycloaddition to give tetracyclic platinum–carbene complexes A was followed by CH insertion at the δ position to afford highly complex products 2. These polycyclic compounds and related products of the title transformation are extremely difficult to access by other means.