イミンの化学的および地域選択性調整可能なPd触媒によるアリルアルキル化によるイミンのアルキル化
Jian-Ping Chen1, Qian Peng, Bai-Lin Lei
1Shanghai-Hong Kong Joint Laboratory in Chemical Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.
Journal of the American Chemical Society
|August 11, 2011
まとめ
イミンのα-カルバニオンは,パラジウム触媒によるアリルアルキル化における有効なヌクレオフィルである. 異なる塩基と溶媒が化学的および地域選択性を制御し,高ステレオ選択性を持つ分岐型または線形製品を生成します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- 合成方法論 合成方法論
背景:
- パラジウム触媒によるアリルアルキレーションは,強力な炭素-炭素結合形成反応である.
- イミン由来カルバニオンを核愛素として使用することは,ユニークな合成の可能性を提供します.
研究 の 目的:
- Pd触媒によるアリルアルキレーションにおけるサイクルおよび非サイクルイミンのα-カルバニオンの使用を調査する.
- 異なる反応条件を用いて,化学的および地域選択性を制御する.
- 反応メカニズムを解明するために.
主な方法:
- イミンのα-カルバニオンをヌクレオフィルとして利用した.
- アリルアルキル化のためのパラジウム触媒を用いた.
- 選択性を調整するために,様々な塩基 (t-BuOK,LDA) と溶媒 (THF,トロウエール) を使った.
- 機械的な提案をサポートするために,DFT計算を行いました.
主要な成果:
- Pd触媒によるアリルアルキル化におけるイミンα-カルバニオンの成功応用を達成した.
- ベース/溶剤システムを調整することで,高い化学的および地域選択性制御が実証されています.
- 主にt-BuOK/THFで枝分かれした製品,LDA/トルエールで線形製品が得られる.
- 両製品タイプにおいて,高い地域および地域隔離選択性が報告されています.
結論:
- イミンα-カルバニオンは,Pd触媒によるアリルアルキル化のための多用途のヌクレオフィルである.
- 反応条件は,製品の分布と選択性に大きく影響する.
- 実験データと計算データと一致するメカニズム的な経路が提案されました.
関連する概念動画
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Imine formation involves the addition of carbonyl compounds to a primary amine. It begins with the generation of carbinolamine through a series of steps involving an initial nucleophilic attack and then several proton transfer reactions. The second part includes the elimination of water, as a leaving group, to give the imine.
Imines are formed under mildly acidic conditions. A pH of 4.5 is ideal for the reaction.
If the pH is low or the solution is too acidic, the reaction slows down in the...
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If the pH is low or the solution is too acidic, the reaction slows down in the...
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