ナザロフサイクル化の効率的な触媒は,隣接するラビル調整部位を持つカチオンイリジウム複合体を用いて行う

Mesfin Janka¹, Wei He, Alison J Frontier

¹Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.

Journal of the American Chemical Society

|June 4, 2004

まとめ

新しいイリジウム (III) 複合体は,ナザロフ循環反応を効率的に触媒化する. この触媒は,ケレーションによって基板を活性化し,アリルビニルとディビニルケトンの効果的な変換を可能にします.

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

背景:

ナザロフサイクル化は,サイクロペンテノンを合成するための重要な反応です.
ナザロフ・サイクル化の効率的な触媒の開発は,依然として活発な研究分野です.

研究の目的:

ナザロフサイクライゼーションにおけるディケーション性Ir (III) 複合体の触媒活性を調べる.
基板-触媒複合体の形成を含む触媒のメカニズムを解明する.

主な方法:

ディケーション性Ir (III) 複合体[IrMe (CO) (dppe (DIB)) ] (BARF) の合成と特徴づけ2.
中間種を検出するための光譜研究 (例えば,NMR,IR)
様々なケトンのナザロフ循環を促進する触媒の効率の評価.

主要な成果:

Ir (III) 複合体は,アリルビニルとディビニルケトンのナザロフサイクルに高い触媒活性を示した.
顕微鏡の証拠は,サイクル化の前に基質-触媒複合体の形成を確認した.
反応の効率は,触媒の電好性と,ケレーションによる基板活性化に関連しています.

結論:

ディカチオンのIr (III) 複合体は,ナザロフサイクル化の非常に効果的な触媒である.
エレクトロフィリックなIr (III) センターによるケレーション補助基板活性化が,触媒過程を駆動する.

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