アリル硫酸化物のフォトアセミゼーションにおけるノンラジカル経路の証拠
1Department of Chemistry, Iowa State University, Ames, IA 50011-3111, USA.
Journal of the American Chemical Society
|March 14, 2002
まとめ
脱硫硫酸化物の光解は主に硫黄の逆転を引き起こし,隣接するステレオセンターに影響を与えなかった. これは,アルファ分裂を回避する光化学的エピメリゼーションメカニズムを示唆しています.
科学分野:
- 有機化学 オーガニック・ケミストリー
- フォトケミストリー フォトケミストリー
- ステレオ化学 ステレオ化学
背景:
- 硫酸化物は,合成における応用がある多用途化合物である.
- 硫酸化物反応のステレオ化学的結果を理解することは,非対称合成に不可欠です.
- 光化学反応は,分子変換のためのユニークな経路を提供します.
研究 の 目的:
- 硫酸化物における光化学的エピメリゼーションのメカニズムを調査する.
- 硫黄酸化物の光分解のステレオ化学的結果を決定するために.
- ホモリティックアルファ割れを伴わない反応経路を探求する.
主な方法:
- (R,S,S,C) -1-デウテリオ-2,2-ジメチルプロピルp-トリル硫酸化物の光分解.
- ステレオ化学的方法を使用して形成されたステレオアイソマーの分析.
- 観察された立体化学的結果に基づく機械的解釈.
主要な成果:
- 光分解により主に (S(S),S(C)) - 1 - デウテリオ-2,2-ジメチルプロピルp-トリル硫酸化物が得られた.
- 硫黄の逆転は,隣接するCHDステレオジェニックセンターの逆転なしに発生しました.
- 他のステレオアイソマーの形成は,より少ない程度で観察されました.
結論:
- 主要なステレオ化学的結果は,硫黄の逆転のみを含むメカニズムを示しています.
- 結果は,同解性アルファ分裂を含むメカニズムに対する証拠を提供します.
- 硫酸化物の光化学的エピメリゼーションは,隣接するステレオセンターを保存する経路を経由して進行することができます.
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