ORS1-0033
The Impact of Boron-Protecting Group Design on the Radical Polymerization Behaviors of Vinylboron Monomers Leading to the Tacticity-Controlled Synthesis of Poly(vinyl alcohol)s
Topic
S1. Polymer Synthesis
When and Where
Sep 29, 2026
17:30 - 17:45
Room 101
Session Chairs
Chang-Geun CHAE
Presenter(s)
Tsuyoshi Nishikawa (Kyoto University)
Co-Author(s)
Abstract
Organoboron Compounds are recognized as the valuable synthetic intermediate due to its versatile transformability in organic reaction. In this presentation, we describe the impact of boron chemistry on polymer synthesis leading to access to conventionally inaccessible polymers [1,2]. Vinylboron compounds, of which boron is directly attached to the vinyl moiety, exhibit radical polymerization ability and post-polymerization transformation affords various novel polymers. For example, post-polymerization hydroxylation of boron pendants gives poly(vinyl alcohol)s. The design of boron protecting group allows us to alter the polymerization behaviors, enabling access to poly(vinyl alcohol) (PVA) derivatives. The radical homopolymerization of vinylboronic acid pinacol ester yields the branched polymer due to the frequent back-biting, and post-hydroxylation affords the branched PVAs [3]. When pinacol group of vinylboron is replaced with anthranilamide with n-alkyl substituent on amide moiety, back-biting is suppressed, affording linear PVAs. Furthermore, introduction of bulky substituent (e.g., 2-methylbutyl group) on amide results in the isotactic polymerization due to the helix induction during polymerization by the steric effect of pendants [4]. When tetrahydrofuran (THF) is used as the substituent on amide, non-classical hydrogen bond between vinyl and oxygen in THF worked to suppress the helix induction, resulting in syndiotactic regulation [5]. Thus, designability and transformability of boron pendants are useful to access the series of PVAs have various primary structures.
[1] Nishikawa, T.* Polym. J., 2024, 56, 873–886.
[2] Suzuki, H.; Nishikawa, T.*; Ouchi, M.* Macromolecules, 2026, 59, 5097–5109.
[3] Kanazawa, T.; Nishikawa, T.*; Ouchi, M.* Macromolecules, 2024, 57, 6750–6758.
[4] Suzuki, H.; Nishikawa, T.*; Ouchi, M.* J. Am. Chem. Soc., 2025, 147, 12672–12685.
[5] Suzuki, H.; Nishikawa, T.*; Ouchi, M.* Nat. Commun., 2026, accepted.
[1] Nishikawa, T.* Polym. J., 2024, 56, 873–886.
[2] Suzuki, H.; Nishikawa, T.*; Ouchi, M.* Macromolecules, 2026, 59, 5097–5109.
[3] Kanazawa, T.; Nishikawa, T.*; Ouchi, M.* Macromolecules, 2024, 57, 6750–6758.
[4] Suzuki, H.; Nishikawa, T.*; Ouchi, M.* J. Am. Chem. Soc., 2025, 147, 12672–12685.
[5] Suzuki, H.; Nishikawa, T.*; Ouchi, M.* Nat. Commun., 2026, accepted.
