ホモキラル・メタル・オーガニック・フレームワークの欠陥リンク:キラル分離能力の調節
Benjamin Slater1,2, Zeru Wang1, Shanxue Jiang1
1Barrer Centre, Department of Chemical Engineering, Imperial College London , London SW7 2AZ, United Kingdom.
Journal of the American Chemical Society
|November 29, 2017
まとめ
ホモキラル金属有機フレームワーク (MOF) に欠陥を導入すると,エナティオメア分離が著しく強化されます. この研究では,欠陥のあるZnBLDMOFを使用した1-フェニルエタノールのエナティオメール過剰が35%増加していることが示されています.
科学分野:
- 材料科学
- 化学工学
- クリスタルグラフィー
背景:
- チラルの分離は,エナンティオメアの同一性により困難である.
- ホモキラル・メタル・オーガニック・フレームワーク (MOF) は,エナチオ分離の有望性を示しています.
- MOFの構造的欠陥は孔の構造と性質を変化させる可能性があります.
研究 の 目的:
- ホモキラルMOFのエナチオ分離能力に欠けているリンク器の欠陥の影響を調査する.
- エナティオメア過剰を改善するために欠陥の濃度を最適化します.
- MOFの構造的欠陥とエナチオ分離性能を相関させる.
主な方法:
- ホモキラルMOF [Zn2{\bdc}{\l-lac}{\dmf}] (ZnBLD) の合成,制御された欠陥リンクナー.
- モノカルボキシル酸リガンド (l-乳酸) の濃度の変化とプロパノ酸の調節剤としての使用
- FTIR,TGA,1H NMR,ICP,PXRDを用いた特徴づけ
- 粉末のX線 difraktion (PXRD) を半最大 (fwhm) で分析して,欠陥レベルを評価する.
主要な成果:
- 欠陥のあるZnBLDMOFは,欠陥のないフレームワークと比較して,1-フェニルエタノールのエナティオメール過剰が35%増加した.
- Zn2+をl-乳酸比に調整すると,欠陥濃度とエナチオセパレーションに影響を与えます.
- モノカルボキシル酸リガンドの濃度が高いと,fwhm値が増加し,欠陥レベルが高くなる同構造MOFが生じる.
結論:
- ホモキラルMOFに欠けているリンク器の欠陥を導入することは,エナチオ分離を強化するための効果的な戦略です.
- リガンド比によって制御される欠陥の濃度は,エナティオメア過剰に直接影響する.
- PXRD fwhm分析は,構造上の欠陥と分離効率を相関させるための貴重なツールとして機能する.
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