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Construction of Polyarylenes with Various Structural Features via Bergman Cyclization Polymerization


Synthetic polymer chemistry is a fundamental part of polymer science, and highly efficient polymerization reactions are essential for the synthesis of high-performance polymers. Development of new synthetic methods for emerging polymer science is of great importance in this regard. Bergman cyclization is a chemical process in which highly reactive aryl diradicals form from enediyne precursors, having a strong impact in a number of fields including pharmaceutics, synthetic chemistry, and materials science. Diradical intermediates stemming from enediynes can cause DNA cleavage under physiological conditions, leading to the strong cytotoxicity of many naturally occurring enediyne antibiotics. Meanwhile, diradical intermediates can quickly couple with each other to construct polyarylenes, providing a novel method to synthesize these conjugated polymers with the advantages of facile and catalyst-free operation, high efficiency, and tailored structure. Moreover, conjugated polymers generated by Bergman cyclization exhibit many remarkable properties, such as excellent thermal stability and good solubility and processability, enabling their further processing into carbon-rich materials. This review presents a brief overview of the trajectory of Bergman cyclization in polymer science, followed by an introduction to research advances, mainly from our group, in developing polymerization methods based on Bergman cyclization, taking advantages of its catalyst-free, byproduct-free, in situ polymerization mechanism to synthesize new polymeric materials with various structures and morphologies. These synthetic strategies include fabrication of rod-like polymers with polyester, dendrimer, and chiral imide side chains, functionalization of carbon nanomaterials by surface-grafting conjugated polymers, formation of nanoparticles by intramolecular collapse of single polymer chains, and construction of carbon nanomembranes on the external and internal surface of inorganic nanomaterials. These polymers with novel structural features have been used in a variety of fields, such as energy transformation, energy storage, catalyst support, and fluorescent detection. Finally, the outlook for future developments of Bergman cyclization in polymer science is presented.

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C-dots or CDs:

Carbon quantum dots




Conjugated microporous polymers


Carbon nanomembranes




Cyclic voltammetry


Dynamic mechanical spectroscopy






Electrochemical capacitors


Electrical double-layer capacitors




Fused aromatic rings


Gel permeation chromatography


Highest occupied molecular orbital


Lowest unoccupied molecular orbital


Methyl methacrylate


Multiwalled carbon nanotubes




Poly(acrylic acid)


Poly(benzyl acrylate)


Polydispersity index


Polyethylene glycol




Polylactic acid


Poly(methyl acrylate)








Quantum dots


Quantum yield


Selected-area electron diffraction


Self-assembled monolayers


Soluble conjugated microporous polymers


Single-chain polymer nanoparticles


Surface-enhanced Raman scattering


Silica-supported carbon nanomembranes


Scanning tunneling microscopy


Tetrabutylammonium fluoride


Transmission electron microscopy




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Financial support by the National Natural Science Foundation of China (21674035, 21474027, 91023008, 20874026, 20704013), Shanghai Shuguang Project (07SG33), New Century Excellent Talents in University, Ph.D. Programs Foundation of Ministry of Education of China, and Shanghai Leading Academic Discipline Project (B502) is gratefully acknowledged. A.H. thanks the Eastern Scholar Professorship and follow-up plan support from Shanghai local government. Y.W. thanks the China Scholarship Council (CSC) for support of his study at The University of Chicago.

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Correspondence to Aiguo Hu.

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This article is part of the Topical Collection “Polymer Synthesis Based on Triple-bond Building Blocks”; edited by Ben Zhong Tang, Rongrong Hu.

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Wang, Y., Chen, S. & Hu, A. Construction of Polyarylenes with Various Structural Features via Bergman Cyclization Polymerization. Top Curr Chem (Z) 375, 60 (2017).

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  • Bergman cyclization
  • In situ polymerization
  • Enediynes
  • Conjugated polymers
  • Two-dimensional polymers