Intramolecular Photoassisted Cycloadditions of Azaxylylenes and Postphotochemical Capstone Modifications via Suzuki Coupling Provide Access to Complex Polyheterocyclic Biaryls

Modular preassembly of azaxylylene
photoprecursors, halogen-substituted
in the aromatic ring, their intramolecular [4 + 4] or [4 + 2] cycloadditions
to tethered unsaturated pendants, and subsequent postphotochemical
capstone modification of the primary photoproducts via Suzuki coupling
provides rapid access to diverse biaryls of unprecedented topology.
This synthetic sequence allows for rapid growth of molecular complexity
and is well aligned with methodology of Diversity-Oriented Synthesis.