結晶における大分子運動のカスケーディング効果:トポタキシ的ポリモルフィック移行がトポケミカルポリメリゼーションへの道を開く

Cijil Raju¹, Gunjan R Ramteke², K V Jovan Jose²

¹School of Chemistry, IISER, Thiruvananthapuram, Kerala 695551, India.

Journal of the American Chemical Society

|April 20, 2023

まとめ

水晶の反応性は予期せぬ変化を起こしますポリモルフィック移行により,非反応性から反応性結晶形態への変換が誘発され,アジド-アルキンサイクル添加反応によってトポケミカルポリメリゼーションが可能となった.

科学分野:

ポリマー化学
クリスタルグラフィー
材料科学

背景:

トポケミカルポリメリゼーションは,オーダーされたポリマーへの経路を提供します.
静的な結晶構造のみに基づいて反応性を予測することは信頼できない.

研究の目的:

ポリモルフィックトランジションによって引き起こされたトポケミカルポリメリゼーションを調査する.
化学反応を可能にする結晶のダイナミクスの役割を探求する.

主な方法:

単一結晶X線 difraktion 構造の変化を監視する.
ポリモルフィックの移行を誘導するための加熱実験
ポリメリゼーションを確認するためのスペクトル分析.

主要な成果:

モノマーが非反応的ポリモルフに結晶し,ヘッド・トゥ・ヘッド・アラインメントがある.
加熱により,単結晶から単結晶 (SCSC) への移行が,頭から尾の並び方に反応するポリモルフに誘発された.
反応性ポリモルフはトポケミカルアジドアルキンサイクル添加 (TAAC) ポリメリゼーションを受けた.

結論:

SCSCのポリモルフィックトランジションは隠されたトポケミカル反応性を解き放つことができます
静的な構造だけでなく結晶のダイナミクスも反応性を予測するのに重要です
この研究は制御されたポリマー合成のための新しい経路を示しています.

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