ベータ・ラクトンからサクシン酸アンヒドリドへの触媒カルボニル化
Yutan D Y L Getzler1, Vinod Kundnani, Emil B Lobkovsky
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, USA.
Journal of the American Chemical Society
|June 4, 2004
まとめ
新しいアルミニウム・コバルト触媒は,一酸化炭素 (CO) とベータ・ラクトンからサクシン酸アンヒドリドを効率的に合成します. この触媒は高い活性と選択性を示し,反応においてステレオ化学的制御が観察される.
科学分野:
- カタリシス カタリシス カタリシス
- オーガニック・シンセシス オーガニック・シンセシス
- 有機金属化学 有機金属化学
背景:
- サクシン酸アンヒドリドは,貴重な化学的中間物質である.
- 容易に入手可能な前駆体からサクシン酸アンヒドリドの効率的な合成が望ましい.
- 既存の触媒方法には選択性が欠けているか,厳しい条件が必要である.
研究 の 目的:
- サクシン酸アンヒドリド合成のための高度に活性で選択的な触媒を開発する.
- 炭素一酸化物 (CO) を用いてベータラクトンの触媒カルボニレーションを調査する.
- 触媒プロセスのメカニズムと立体化学的結果を解明する.
主な方法:
- 新しいアルミニウム・コバルト触媒の合成と特徴付け: [(N,N'-bis(3,5-di-tert-butylsalicylidene) フェニレンダイアミノ) Al (((THF) 2) [Co (((CO) 4].
- 様々なベータラクトンと200psiのCOの触媒カルボニル化反応.
- 反応産物の分析は,スペクトロスコピ的方法を用いて行われ,ステレオ化学を決定する.
主要な成果:
- 触媒はベータプロピオラクトンを効率的にサクシン酸アンヒドリドに変換し,高収量になります.
- (R) -β-ブチロラクトンが (S) -メチルサッキン酸アンヒドリドに変換され,ステレオ化学が完全に逆転した.
- cis-2,3-dimethyl-beta-propiolactoneは,トランス-2,3-dimethylsuccinic anhydrideを独占的に生成しました.
結論:
- COとβ-ラクトンからサクシン酸アンヒドリドを合成するための明確に定義された,高度に活性で選択的な触媒が開発されました.
- 触媒プロセスは予測可能なステレオ化学的制御で進行し,特定の反応機構を示す.
- 提案されたメカニズムは,ベータラクトンに対する[Co(CO) 4) -による核愛的攻撃を伴うもので,COの挿入とアンヒドリドの形成が続く.
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