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Updated: Jan 11, 2026

Atom Transfer Radical Polymerization of Functionalized Vinyl Monomers Using Perylene as a Visible Light Photocatalyst
Published on: April 22, 2016
Halogen Atom Transfer (XAT)-Enabled Transition-Metal-Free Radical Annulation for the Construction of
Chen Zhou1,2, Pei-Shang Li2, Xue-Qing Wang2
1School of Chemical Engineering and Materials, Changzhou Institute of Technology, Changzhou 213032, China.
Abstract:
A transition-metal-free radical annulation strategy enabled by halogen atom transfer (XAT) has been developed for the direct construction of phenanthrene-derived polycyclic aromatic hydrocarbons (PAHs) from 2-iodobiaryls and terminal alkynes. This visible-light-mediated protocol proceeds under mild conditions and exhibits broad substrate scope, high regioselectivity, and excellent functional group tolerance. Importantly, the method can be applied iteratively to achieve homologative aromatic extension, allowing efficient access to structurally diverse and complex PAHs in just a few steps. Mechanistic studies support a radical pathway involving α-aminoalkyl radical-mediated XAT, vinyl radical cyclization, and a quantum tunneling-enabled aromatization process. This work provides a practical and scalable approach to PAHs that circumvents the limitations of conventional transition metal catalysis.
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