クロミウム(III) オクタエチルポルフィリナトテトラカルボニルコバルト酸:エポキシードカルボニレーションの高度に活性で,選択的で,多用途な触媒です
Joseph A R Schmidt1, Emil B Lobkovsky, Geoffrey W Coates
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, USA.
Journal of the American Chemical Society
|August 11, 2005
まとめ
新しく開発されたクロム・ポルフィリン・カタリストにより,エポキシドから貴重なラクトンの効率的な合成が可能になる. この触媒は,高活性,選択性,およびエポキシードカルボニル化反応に対する機能群耐性を示しています.
科学分野:
- 有機金属化学 有機金属化学
- 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
背景:
- エポキシードカルボニレーションは,ラクトンを合成するための重要な変換です.
- 効率的で選択的な触媒の開発は依然として課題です.
研究 の 目的:
- エポキシードカルボニレーションのための高活性で選択的なポルフィリンベースの触媒を開発する.
- 合成的に有用なラクトンの広範な配列を合成するために.
主な方法:
- [[[OEP]]Cr[[THF]]2][[[Co[[CO]]4]複合体の合成と特徴づけについて
- 制御された反応条件下で様々なエポキシドの触媒カルボニル化.
- 反応のステレオ化学を分析し,メカニズムを解明する.
主要な成果:
- 触媒 [(OEP) Cr ((THF) 2) [Co ((CO) 4) ] (1) は,優れた回転数 (最大10,000) と周波数 (最大1670h ((-1)) を示しています.
- レジオセレクティブカルボニル挿入は,阻害の少ないエポキシード炭素で発生します.
- 多様な機能群に対する高い耐性で,様々なアリファティック・ラクトンとサイクロアリファティック・ラクトンの合成を可能にする.
- 反応条件を制御することによって達成されるベータまたはガンマラクトン異体体の独占的生産.
結論:
- 新しいポルフィリン・クロム・コバルト複合体は,エポキシードカルボニレーションを効率的に触媒化する.
- 触媒は,様々なラクトンの迅速かつ選択的な合成を容易にする.
- ガンマ-ラクトン形成の提案されたメカニズムは,反応ステレオ化学の洞察を提供します.
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