ラクトンの選択的リング開封ポリメリゼーションのための二重触媒:単純化への進化
Stefan Naumann1, Philip B V Scholten1, James A Wilson1
1Department of Chemistry, University of Warwick , CV4 7AL Coventry, U.K.
Journal of the American Chemical Society
|October 28, 2015
まとめ
オーガノカタリストと組み合わせた単純なルイス酸は,マクロラクトンのリング開きポリメリゼーション (ROP) を効率的に触媒化する. この協力的触媒アプローチは,低コストの前体を使って,ポリマーの構造と特性を制御します.
科学分野:
- ポリマー化学
- カタリシス
- 有機合成
背景:
- リングオープニングポリメリゼーション (ROP) は,伝統的に複雑な単一サイト触媒に依存しています.
- ルイス酸と有機触媒を用いた協同触媒は,RPに対するよりシンプルで効果的な代替手段である.
研究 の 目的:
- ROPのためのルイス酸とN-ヘテロサイクリックカルベンの協力効果を調査する.
- この触媒システムを用いてモノマー選択性とコポリマー組成の制御を調査する.
主な方法:
- N-ヘテロサイクルカルベン (DBU,DMAP) と様々なルイス酸 (MgX2,YCl3,AlCl3) の組み合わせを使用した.
- ペンタデケラクトンおよび他のサイクル (ダイエスター) のRPを実施した.
- ルイス酸とオルガン塩基の選択に基づいて,触媒の活性と選択性を分析した.
主要な成果:
- ペンタデカラクトンの迅速かつ効率的な ROP を,協力的触媒システムを使用して達成した.
- ルイス酸の明確な活動傾向が確立された: MgX2 ≫ YCl3 ≫ AlCl3 と MgI2 > MgBr2 > MgCl2.
- モノマー選択的ROPと,賢明なルイス酸選択によるコポリマー組成の制御が実証されている.
結論:
- 単純なルイス酸と有機触媒による協同触媒は ROPの強力な戦略です.
- この方法は,アクセシブルな前駆体から調整可能な性質を持つ複雑なポリマーを合成することを可能にします.
- ルイス酸の選択はモノマー選択性を決定し,ポリマー構造を正確に制御することができます.
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