ダイアゾエステルは分子内 (4 + 2) サイクロアディションにおけるディエノフィルである:メカニズムの計算的探求

Abing Duan^1,2, Peiyuan Yu², Fang Liu²

¹Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education; School of Chemistry and Environment, South China Normal University , Guangzhou 510006, China.

Journal of the American Chemical Society

|January 19, 2017

まとめ

この研究では,ディアゾ化合物を用いてディエルス-アルダー反応を調査しています. 分子内反応は,分子間反応とは異なり, (4 + 2) サイクル添加経路を特異的に好みます.

科学分野:

有機化学
コンピュータ化学

背景:

ダイエルス・アルダー反応は有機合成において極めて重要です
ディアゾ化合物は,ヘテロディエノフィールまたは1,3-二極体として作用する.
反応メカニズムの理解は合成戦略を導きます

研究の目的:

ダイオゾ化合物のディエルス・アルダー反応を研究する.
分子間対分子内システムのダイアゾ化合物の反応性を比較する.
これらのサイクル添加の選択性を支配する要因を明らかにする.

主な方法:

M06-2X関数を用いた密度関数理論 (DFT) の計算.
歪み/相互作用モデルを用いた分子間システムの分析
分子内および分子間経路の計算結果の比較

主要な成果:

この研究は,ダイアゾ化合物をヘテロディエノフィールとして使った最初の実験例を示している.
分子間反応は1,3-二極サイクロアディションを好む.
結合効果による分子内反応は, (4+2) サイクル添加を強く支持する.

結論:

ディアゾ化合物は,ヘテロディエノフィールとしてディエルス-アルダー反応に参加することができる.
反応経路の選択性は,システムが分子間または分子内であるかどうかに大きく依存する.
分子内反応における結合は,ダイエルス-アルダー経路を好み,サイクロアディションの結果に大きく影響する.

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