カチオンパラジウムアルキル複合体のアクリロニトリル挿入反応
Fan Wu1, Stephen R Foley, Christopher T Burns
1Department of Chemistry, The University of Chicago, 5735 South Ellis Avenue, Chicago, IL 60637, USA.
Journal of the American Chemical Society
|February 11, 2005
まとめ
アクリロニトリル (AN) を含むパラジウム触媒は,ANを挿入するN結合アダクトを形成し,集合種となる. 集積と低挿入反応性は,これらの触媒でANのポリメリゼーションを妨げます.
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
- ポリメリゼーションによる.
背景:
- アクリロニトリル (AN) を含むパラジウム触媒反応の調査.
- パラジウム複合体の様々なリガンド・スキャフォールド (L(2) の探査.
研究 の 目的:
- L(2) PdMe+種のアクリロニトリルとの反応性を理解する.
- アクリロニトリル挿入ポリメリゼーションとコポリメリゼーションの障害を特定する.
主な方法:
- NMR,ESI-MS,IR光譜を用いたパラジウム-ANアダクトの合成と特徴付け.
- 挿入反応の調査と,その後の製品の特徴付け.
- エチレン調整と挿入に関する比較研究.
主要な成果:
- パラジウム前駆体からN結合のアクリロニトリル添加物 (L(2) Pd(Me) ((NCCH=CH(2)) +) の形成.
- 2,1-ほとんどのアダクト (3a-e) にANを挿入すると,L(2) Pd{CH(CN) Et}+が得られ,それらは [L(2) Pd{CH(CN) Et}]{n) n) +に集約されます.
- アクリロニトリル挿入はエチレン挿入よりも遅いため,アグレゲーションはモノマー調整と競合する.
結論:
- パラジウム-アルキル種の集積は,アクリロニトリル挿入ポリメリゼーションの重要な障壁です.
- パラジアム-アルキル-基板複合体の低挿入反応性は,さらにポリメリゼーションを阻害する.
- (2) PdR+触媒は,有効なANポリメリゼーションまたはコポリメリゼーションの課題に直面しています.
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