CpCo(CO) の溶媒依存スピン状態の均衡の超高速観測
Justin P Lomont1, Son C Nguyen, Jacob P Schlegel
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|January 14, 2012
まとめ
暫定的な有機金属光産物は,溶媒の相互作用によって影響されるシングレットとトリプレートスピン状態の間の均衡状態で存在することができます. この研究は,両方のスピン状態に対する溶媒の調整を明らかにし,ピコ秒の時間スケールでの反応性に影響を与えます.
科学分野:
- 有機金属化学 有機金属化学
- フォトケミストリーは,写真化学です.
- 物理化学 物理化学
背景:
- 16エレクトロンの有機金属光産物には,典型的には三重の反応性がある.
- 溶媒と一時的な光産物との相互作用は完全に理解されていません.
- 移行金属複合体のスピン状態の均衡は知られているが,過渡種ではめったに観察されない.
研究 の 目的:
- 16電子の光産物CpCo(CO) のスピン状態の行動を調査する.
- フォトプロダクトのスピン状態に溶媒の影響を判断する.
- 変異種におけるスピン状態均衡の反応性の影響を調査する.
主な方法:
- フォトプロダクトの形成を監視するための時間解像度赤外線スペクトロスコーピー.
- 様々な溶媒環境で実施された実験.
- 実験的観測を裏付けるための電子構造理論の計算.
主要な成果:
- 三重のCpCo (((CO)) 前駆体から2つの異なるソルバートモノカルボニル光産物の観察.
- これらの光産物の割り当ては,シングレットおよびトリプレットCpCo (((CO)) ((溶媒)) 複合体である.
- 溶媒が光産物の両方のスピン状態に調整している証拠.
結論:
- 溶剤依存のスピン状態の均衡は,CpCo(CO) フォトプロダクトに存在する.
- スピン・クロスオーバーは反応性を阻害しない;熱力学的安定性は,スピン状態を決定する.
- これは,安定したスピン状態の均衡と,両方の状態への溶媒の調整を持つ一時的な光産物の最初の観測です.
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