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イリジウム触媒によるエナンチオおよび地域選択性アリルエステル化によるアリルエステル化

Jianping Qu¹, Lydia Roßberg, Günter Helmchen

¹Organisch-Chemisches Institut der Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany.

Journal of the American Chemical Society

|January 16, 2014

まとめ

この研究は,高い選択性を持つ分岐性アリルエステルを合成するための新しいイリジウム触媒反応を提示しています. この方法では,カルボキシラートとアリルリン酸塩を直接変換し,時には,強化されたエナティオメア過剰に対する運動解像度を含む.

科学分野:

有機金属化学有機金属化学
オーガニック・シンセシスオーガニック・シンセシス
カタリシスカタリシスカタリシス

背景:

アリルエステル化は,有機合成における重要な変換である.
エナチオセレクティブとレジオセレクティブの方法の開発は,依然として重要な課題です.
イリジウム触媒は,C-C結合形成のためのユニークな反応性を提供します.

研究の目的:

直接のアリルエステル化のための新しいIr-触媒化された方法を開発する.
枝分かれしたアリルエステルの合成において,高いエナンチオセレクティブ性と地域選択性を達成する.
エステル化プロセス中の運動解像度の可能性を調査する.

主な方法:

イリジウム複合体を触媒として利用する.
カーボキシラートを核愛素として使用する.
線形アリルリン酸塩を電愛体として使用する.
反応条件を調査して,最適な収穫量と選択性を求めます.

主要な成果:

高いエナチオセレクティブ性と地域セレクティブ性を有する分岐型アリルエステルの合成が成功しました.
カーボキシラートが,Ir触媒によるアルリル置換における有効なヌクレオフィルであることの実証.
特定のケースにおける運動解像度の観察により,変化したエナティオメール過量が生じます.

結論:

開発されたIr-触媒化アリルエステル化は,価値ある枝分かれアリルエステルへの直接的な経路を提供します.
この反応は,ステレオケミストリーとレジオケミストリーに対する優れた制御を示しています.
同時の運動解像度は,ステレオ化学制御の追加の層を提供します.

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