UDFTとMCSCFは,エネダイヌスの光化学的ベルグマンサイクル化の記述である
A E Clark1, E R Davidson, J M Zaleski
1Department of Chemistry, Indiana University, Bloomington, IN 47405-7102, USA.
Journal of the American Chemical Society
|July 18, 2001
まとめ
cis-1,5-hexadiyne-3-eneのベルグマン循環は,競合する異体化と水素抽出により,トリプル (13B) 状態を通じた可能性は低い. 光化学的循環は,シングレット (21A) の潜在エネルギー表面ではより妥当である.
科学分野:
- コンピューティング・ケミストリー
- オーガニック・フォト化学
背景:
- ベルグマン循環は,p-ベンジンの中間物質を形成する有機化学の重要な反応である.
- 潜在エネルギー表面 (PES) を理解することは,反応経路と可行性を予測するために極めて重要です.
研究 の 目的:
- cis-1,5-hexadiyne-3-ene.のベルグマンサイクリングのための潜在的なエネルギー表面を調査する.
- 最も妥当な光化学サイクリング経路を決定する.
主な方法:
- UDFT,CI,CASCI,CASSCF,CASMP2.2を含む様々な計算化学の方法を活用しました.
- 反応のシングレットおよびトリプレット潜在エネルギー表面 (PES) の計算.
主要な成果:
- 三重 (13B) 状態の経路は,競合するシス・トランス・イソメリゼーションと水素原子抽象による可能性は低い.
- シングレット (21A) 潜在エネルギー表面は,より合理的な,しかし,より少ないエクソサーミック,光化学サイクル経路を提供します.
- p-ベンジンの中間体は,シングレットカルベンとダイラジカルの両方の特性を有するユニークな電子構造を示しています.
結論:
- cis-1,5-hexadiyne-3-eneのBergmanサイクル化は,トリプレット経路では好まれない.
- 光化学的サイクリングは,シングレット (21A) PES.で発生する可能性が高い.
- p-ベンジンの中間物質の電子構造は複雑で,反応のダイナミクスに影響を与えます.
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