金属上分子ポリマーの同時包装ポリモルフィズムを解析

Anja Langenstroer¹, Kalathil K Kartha¹, Yeray Dorca²

¹Organisch-Chemisches Institut , Universität Münster , Corrensstraße 40 , 48149 Münster , Germany.

Journal of the American Chemical Society

|February 21, 2019

まとめ

この研究は,2つの異なる安定した超分子ポリマーを形成するプラチナ (II) 複合体を明らかにしています. 独特の包装構造を持つこれらのポリモルフは室温で相互変換せず超分子組成に関する新しい洞察を提供しています

科学分野:

超分子化学
材料科学
協調化学

背景:

ポリモルフィズムは生物学的および自己組み立てシステムで一般的です.
超分子ポリマーは,競合する運動および熱力学的種で経路の複雑性を示すことができます.
暫定的な運動種は通常寿命が短く,熱力学的製品に急速に変換されます.

研究の目的:

安定した,競合する超分子ポリマーを形成する能力を持つπ結合のPt (II) 複合体を調査する.
これらのポリモルフの異なる分子包装モードと安定化メカニズムを解明する.
異なる超分子種の形成と安定性を制御するための条件を確立する.

主な方法:

非極性環境におけるπ結合のPt (II) 複合体の自己組成.
実験的技術と理論的計算を用いた超分子ポリマーの特徴化.
段階図とアニリング研究によるポリモルフの安定性の決定

主要な成果:

Pt(II) 複合体は,2つの異なる超分子ポリマー (A:スライド,B:シドパラレル) に自己組み立てられます.
ポリモルフAとBは,室温で少なくとも6ヶ月間,相互変換を示さず,驚くべき安定性を示す.
非従来のN-H··Cl-PtとN-H··O-アルキル相互作用は,それぞれポリモルフAとBを安定させる.
段階図は,両種の安定性条件 (温度,濃度,冷却速度) を正確に定義します.
ポリモルフAは,高温解熱でモノマー形成によってゆっくりとBに変換することができる.

結論:

このシステムは,結晶のポリモルフィズムに似た,高分子ポリマーにおける安定した共存ポリモルフィズムを示している.
セルフアセンブリ条件の正確な制御は,異なる超分子ポリモルフの選択的形成と分離を可能にします.
この発見は結晶工学の原理と超分子ポリメリゼーションの橋渡しとなり機能的な材料の設計に新たな道を開きます

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