ge(100) - 2x1 のニトリル反応における競争と選択性
Michael A Filler1, Collin Mui, Charles B Musgrave
1Departments of Chemical Engineering and Materials Science and Engineering, Stanford University, Stanford, California 94305, USA.
Journal of the American Chemical Society
|April 17, 2003
まとめ
ゲルマニウム (Ge) ((100) - 2x1) 表面のニトリル群結合が研究されました. ニトリルグループは直接結合に不利ですが,アルケンの反応が優勢で,保護グループとして使用することを示唆しています.
科学分野:
- 表面科学とは,地表科学である.
- 有機化学 オーガニック・ケミストリー
- 材料科学 材料科学とは
背景:
- ニトリル機能群 (R-CN) は有機合成において極めて重要です.
- ゲルマニウムのような半導体材料の表面化学を理解することは,新しい材料とプロセスの開発に不可欠です.
研究 の 目的:
- Ge(100) - 2x1の表面上のニトリル機能群の結合行動を調査する.
- この表面上の様々なニトリル含有分子の選択性と競争に影響を与える要因を決定する.
- 表面化学における保護群としてのニトリル群の可能性を調査する.
主な方法:
- 多重内反射赤外線スペクトロスコピーを用いた実験調査.
- 密度関数理論の計算を用いた理論的分析.
- 探査分子の研究:アセトニトリル,2-プロペネニトリル,3-ブテネニトリル,4-ペンテネニトリル.
主要な成果:
- アセトニトリルは,熱力学および運動的要因のために,室温でGe(100) - 2x1表面に反応しません.
- 2-プロペニニトリルの場合,支配的な表面アダクトは, [4+2] サイクロアディション産物 (1954 cm−1のケテニミネ伸縮) と [2+2] C=C サイクロアディション産物 (ニトリル伸縮は2210 cm−1の近く) である.
- 3-ブテンニトリルと4-ペンテンニトリルは,1954cm−1に近い振動モードを示しており,これは結合ニトリルへのイソメリゼーションに起因する.
結論:
- ニトリル機能群のみを含む直接結合経路は,室温でGe(100) - 2x1に対して熱力学的に不利である.
- アルケンのサイクル添加反応は,この表面での多機能ニトリルの支配的な経路です.
- ニトリル機能群は,表面化学における真空互換性保護群として機能する可能性がある.
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