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Updated: May 16, 2025

Microwave-Assisted Preparation of 1-Aryl-1H-pyrazole-5-amines
Published on: June 23, 2019
Aryne Polymerization Enabled by Pyrazole-Induced Nucleophilic Aromatic Substitution
Hayato Fujimoto1,2, Shisato Yamamura1, Mamoru Tobisu1,2
1Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
Abstract:
Despite the widespread use of arynes in organic synthesis, their polymerization remains a significant challenge due to the intrinsic instability and short lifetime of aryne intermediates. Here, we report a method for aryne polymerization using a simple organonucleophile, N-arylpyrazole, as an initiator. This polymerization proceeds via a unique pyrazole-induced nucleophilic aromatic substitution mechanism, facilitating the formation of poly(ortho-arylene)s with narrow polydispersity and well-defined structures. The high chemical stability of N-arylpyrazole allows for a broader scope of applications, including aryne polymerization at the side chain of preformed polymers (graft polymerization) and the synthesis of star-shaped poly(ortho-arylene)s.
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