Double-Tandem [4_π+2_π]·[2 _π+2_π]·[4_π+2_π] ·[2_π+2_π] Synthetic Sequence with Photoprotolytic Oxametathesis and Photoepoxidation in the Chromone Series

摘要

Chromones are introduced into a double-tandem [4_π+2 _π]·[2_π+2_π]·[4 _π+2_π]·[2_π+2_π] synthetic sequence, culminating in photoprotolytic oxametathesis, which leads to an expeditious growth of molecular complexity over a few experimentally simple steps. The overall reaction can potentially be utilized in diversity-oriented synthesis, as it allows for three or more diversity inputs furnishing novel unique polycyclic scaffolds decorated with a variety of functionalities and aromatic/heterocyclic pendants. The polycyclic alkenes, resulting from the oxametathesis step, were found to undergo efficient and clean photoinduced epoxidation when irradiated in the presence of molecular oxygen.