銅で触媒化された原子移転ラジカルポリメリゼーション (Cu-ATRP) のリガンドおよびイニシアター効果のための機械的に導かれた予測モデル
Cheng Fang1,2, Marco Fantin3, Xiangcheng Pan3
1Department of Chemistry , University of Pittsburgh , Pittsburgh , Pennsylvania 15260 , United States.
Journal of the American Chemical Society
|April 13, 2019
まとめ
この研究では,銅で触媒化された原子移転ラジカルポリメリゼーション (Cu-ATRP) の移行状態を計算的に分析しています. 触媒の電子特性,リガンドのステリック,および骨幹の柔軟性が活性化/非活性化率を制御し,反応性の予測モデルを可能にすることを明らかにしています.
科学分野:
- ポリマー化学
- コンピュータ化学
- カタリシス
背景:
- 銅触媒原子移転基ポリメリゼーション (Cu-ATRP) は,広く使用されている制御されたポリメリゼーション技術である.
- 機械学的な研究は存在するが,活性化/無活性化均衡の移行状態は計算上未調査のままである.
- Cu-ATRP率に対するリガンドとイニシアター効果の理解は限られている.
研究 の 目的:
- Cu-ATRP活性化トランジション状態の最初の計算分析を実行します.
- アクティベーションとデアクティベーションの割合に影響を与える要因を明らかにする.
- Cu-ATRPの反応性を予測するモデルを開発する.
主な方法:
- Cu-ATRP活性化移行状態の計算分析
- Br原子の移転幾何学と相互作用を研究する.
- 電子,ステリック,および柔軟性の記述者を識別する.
- 多変量線形回帰は,記述子を実験データと相関させる.
主要な成果:
- Br原子の移転は,ポリマー鎖の末端とリガンドの相互作用による異常な曲げられた幾何学によって起こります.
- アクティベーション/デアクティベーション率は,触媒の電子特性とリガンド・イニシアター・ステリック・レプルションに依存する.
- リガンドの骨格の柔軟性は活性化に大きく影響する.
- HOMOエネルギー,埋もれた体積,そして歪曲エネルギーが 鍵となる特徴です.
- 高精度 (平均誤差 < ±2 kcal/mol) のリガンドとイニシアター効果の予測モデルを開発した.
結論:
- この研究はCu-ATRP移行状態に関する最初の計算洞察を提供します.
- 確立された記述子と予測モデルは,Cu-ATRPの反応性を理解し調整するための堅固な方法を提供します.
- 発見は,Cu-ATRPのメカニズム的理解と実践的応用を進める.
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