室温のイオン性液体で溶質核好性を操作する
Lorna Crowhurst1, N Llewellyn Lancaster, Juan M Pérez-Arlandis
1Contribution from the Department of Chemistry, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom.
Journal of the American Chemical Society
|September 16, 2004
まとめ
イオン性液体は,塩化物イオンに対する無活性化作用とは異なり,アミンの核好性を高めます. この反応性の違いは,主に活性化エントロピーの変化と溶媒の水素結合特性によるものです.
科学分野:
- 物理化学 物理化学
- 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:
- イオン性液体 (ILs) は,ユニークな性質を持つ調節可能な溶媒です.
- 核愛反応に対するILの効果を理解することは,合成化学にとって極めて重要です.
- ILsにおける中性電荷核愛子の行動は,イオン性核愛子よりも調査が少ない.
研究 の 目的:
- 充電中性アミン核粒子の反応性に対するILの影響を調査する.
- ILsにおけるアミンの核好性を分子溶媒と比較する.
- これらの反応性変化を左右する要因を解明する.
主な方法:
- (n) ブチラミン, (n) ディブチラミン, (n) トライブチラミンとメチルp-ニトロベンゼン硫酸塩の反応を研究した.
- 3つのイオン性液体を使用した: [bmpy][N(Tf)(2) ], [bmpy][OTf],および [bmim][OTf].
- ILsの反応性を二塩基メタンとアセトニトリルと比較し,アイリング活性化パラメータとカムレット-タフト溶媒パラメータを分析した.
主要な成果:
- 研究されたすべてのアミンは,分子溶媒と比較して,イオン性液体における強化された核好性を示した.
- イオン性液は,塩化イオン核愛子を無効化し,アミンの行動と対照的です.
- 活性化エントロピーの変化は,観察された反応性傾向の主な原動力として特定されました.
結論:
- イオン性液体は,中性電荷の核性粒子の反応性を著しく調節する.
- ILsとヌクレオフィルの間の水素結合相互作用は,観察された効果において重要な役割を果たします.
- ILsが充電されたヌクレオフィールと中性ヌクレオフィールに与える異なった影響は,それらの複雑な溶解行動を強調します.
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