Facile and Versatile Synthesis of End‐Functionalized Poly(phenylacetylene)s: A Multicomponent Catalytic System for Well‐Controlled Living Polymerization of Phenylacetylenes

• Published in: Angewandte Chemie International Edition 2020-05, Vol.59 (22), p.8670-8680
• Main Authors: Taniguchi, Tsuyoshi, Yoshida, Takumi, Echizen, Kensuke, Takayama, Kokoro, Nishimura, Tatsuya, Maeda, Katsuhiro
• Format: Article
• Language: English
• Subjects: Aromatic compounds; boronic acids; living polymerization; Molecular weight; phenylacetylenes; Polymerization; Polymers; Polyphenylacetylene; Rhodium
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202000361

A rhodium‐based multicomponent catalytic system for well‐controlled living polymerization of phenylacetylenes has been developed. The catalytic system is composed of readily available and bench‐stable [Rh(nbd)Cl]2, aryl boronic acid derivatives, diphenylacetylene, 50 % aqueous KOH, and PPh3. This system offers a method for the facile and versatile synthesis of various end‐functionalized cis‐stereoregular poly(phenylacetylene)s because components from aryl boronic acids and diphenylacetylene were introduced to the initiating end of the polymers. The polymerization reaction shows a typical living nature with a high initiation efficiency, and the molecular weight of the resulting poly(phenylacetylene)s can be readily controlled with very narrow molecular‐weight distributions (Mw/Mn=1.02–1.09). The experimental results suggest that the present catalytic system has a higher polymerization activity than the polymerization activities of other rhodium‐based catalytic systems previously reported. All's well that ends well: Various end‐functionalized poly(phenylacetylene)s have been synthesized by polymerization using a multicomponent catalytic system composed of readily available and bench‐stable reagents (see picture). Owing to the high reactivity and living nature of the polymerization, which has a high initiation efficiency (IE), the molecular weight of the obtained poly(phenylacetylene)s could be readily controlled with a very narrow polydispersity index (PDI).