ラジカルケージ効果:様々な溶媒のマイクロ粘度を用いたラジカルケージペアの再結合効率の予測

Justin T Barry¹, Daniel J Berg¹, David R Tyler¹

¹Department of Chemistry and Biochemistry, University of Oregon , 1253 University of Oregon, Eugene, Oregon 97403, United States.

Journal of the American Chemical Society

|September 22, 2017

まとめ

マイクロ粘度ではなく大量の粘度がゲミナイトの根幹対における根幹再結合効率を正確に予測しますこの発見は様々な溶媒と混合物に適用され,化学反応の精密な理解を可能にします.

科学分野:

物理化学
化学運動学
溶媒効果

背景:

反応メカニズムを理解するために,急性再結合の効率は極めて重要です.
大量の粘度 (マクロ粘度) は,これらの効率をモデル化するために伝統的に使用されています.
単にマクロビスコシティに基づいて再結合を予測する際には限界がある.

研究の目的:

ゲミナート基子の再結合効率と溶媒特性との相関を確立する.
ミクロビスコシティとマクロビスコシティの役割を研究する.
様々な溶媒システムにおける微小粘度相関を検証する.

主な方法:

探査機の拡散係数を測定するために,NMR DOSYスペクトロスコーピーを用いて溶媒の微小粘度を決定する.
ラジカル再結合効率 (F_cP) と測定された微小粘度とを相関させる.
多様な溶媒 (非極性,芳香性,極性,水素結合) と混合物での相関の試験

主要な成果:

マイクロ粘度は,マクロ粘度と比較して,ラジカル再結合効率を予測するための優れたパラメータです.
この相関は,混合物を含む幅広い溶媒システムに当てはまります.
選択的溶解,溶媒の極性,およびラジカル回転は,F_cP-マイクロ粘度関係に大きな影響を与えない.

結論:

マイクロ粘度は,ゲミナート・ラジカル再結合に対する溶媒の影響をより正確に記述する.
この発見は,溶液中の反応結果を予測するための洗練されたモデルを提供します.
この方法は,様々な化学環境で広く適用できます.

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