2座標のNi (I) アルキルおよびアリル複合体の合成と反応性
Carl A Laskowski1, Donald J Bungum, Steven M Baldwin
1Gordon Center for Integrative Science, Department of Chemistry, The University of Chicago , Chicago, Illinois 60637, United States.
Journal of the American Chemical Society
|November 19, 2013
まとめ
この研究は,大量のN-ヘテロサイクリックカルベンのリガンドを用いて,新しい2座標ニッケル (((I) アルキルおよびアリル複合体の合成を詳細に説明しています. これらの複合体はアルキルブロミドと反応し,ニッケル媒介による変異の根本的なメカニズムを示唆する.
科学分野:
- 有機金属化学 有機金属化学
- ニッケル・カタリシス
- カーベネ・リガンド開発
背景:
- 2座標ニッケル複合体は希少であり,非常に反応性があります.
- 大量のN-ヘテロサイクリックカルベン (NHC) リガンドは,低座標メタルセンターを安定させる.
研究 の 目的:
- 新しい2座標ニッケル (((I) アルキルおよびアリル複合体を合成し,特徴づけること.
- これらの低調整ニッケル種のアルキルハリドとの反応性を調査するために.
主な方法:
- [(IPr) Ni(μ-Cl) ]2 (1-Cl) の合成とその有機金属反応剤との反応.
- その結果生じる2座標ニッケル複合体の特徴.
- ニッケル (((I) アルキル複合体とアルキルブロミドの反応.
主要な成果:
- 2つの座標ニッケル (I) アルキルおよびアリル複合体, (IPr) Ni (CH) Si (SiMe3) 2と (IPr) Ni (dmp) を成功して合成しました.
- アルキルブロミドとの反応で3座標のNi ((II) アルキルハリド複合体の形成が観察されました.
- ニッケル (((I) アルキル複合体のアルキルハリド化物との反応のための過激なメカニズムを支持する証拠を集めました.
結論:
- 新しい低座標ニッケル ((I)) 複合体への合成経路を確立しました.
- アルキルハリド反応中にこれらの複合体が激素経路に参加する可能性を実証した.
- 反応性ニッケル種を安定させるのに大型のNHCリガンドの重要性を強調した.
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