フォト誘発イオン対内球電子移転・可逆加分連鎖移転ポリメリゼーション
Qianyi Wang1, Feng-Yang Bai2, Yinling Wang1
1State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200438, China.
Journal of the American Chemical Society
|October 20, 2022
まとめ
ズウィテリオン系オルガノボランは,可逆的添加分裂連鎖移転ポリメリゼーションによる新しい光誘発イオン対内球電子移転機構によって精密なポリマー合成を可能にします. この方法は,高い触媒活性と広範なモノマー互換性を提供します.
科学分野:
- ポリマー化学
- 有機合成
- 光触媒
背景:
- フォトレドックス媒介による可逆性無活性化 (RDRP) は,精密なポリマー合成を可能にするが,多くの場合,効率的な光触媒を必要とする外球電子移転 (OSET) に依存する.
- 既存のRDRP方法は,触媒の要件とメカニズム上の制約のために制限に直面しています.
研究 の 目的:
- リバーシブル・アディション・フラグメンテーション・チェーン・トランスファー (RAFT) ポリメリゼーションの光触媒としてのズウィトリアン・オーガノボラン ([L2B]+X-) を導入し,調査する.
- このシステムにおける光誘導イオン対内球電子移転 (IP-ISET) メカニズムを解明する.
主な方法:
- ズウィテリオン製オーガノボラン ([L2B]+X-) の合成
- RAFTポリメリゼーションでの応用
- 電子パラマグネティック共振 (EPR) 基質捕捉,NMRスペクトロスコピー (1H/11B),スペクトロ電気化学スペクトロスコピー,一時吸収スペクトロスコピー,理論的計算,光発光抑制を用いたメカニズム解明.
- マトリックス・アシスタント・レーザー・デソルプション・イオニゼーション・タイム・オブ・フライト・マススペクトロメトリ (MALDI-TOF MS) を用いたポリマー製品の特徴化.
主要な成果:
- IP-ISETメカニズムと根幹形成 ([L2B]•) は,さまざまなスペクトル学および計算方法によって確認されました.
- 光発光スチーニングは,活性触媒種[L2B]+[ZCS2]-の*in situ*形成を示した.
- ポリメリゼーションは,PPB触媒の負荷,広範囲のモノマー,フェノール阻害剤に対する耐性,超高分子量ポリマーの合成で高い触媒活性を示した.
結論:
- 開発されたプロトコルは,フォトレドックスRDRPのための新しいIP-ISETメカニズムを使用して,OSETベースのメソッドの限界を克服します.
- ズウィトリオン性オルガノボランはRAFTポリメリゼーションの効果的な光触媒であり,望ましい特性を有する正確なポリマー合成を可能にします.
- この研究は,有機変換とポリメリゼーションの方法のための貴重な新しいアプローチを提供します.
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