アリルヨーデードと11グループジメチルメタラートのガス相反応性
Nicole J Rijs1, Naohiko Yoshikai, Eiichi Nakamura
1School of Chemistry, The University of Melbourne, Victoria 3010, Australia.
Journal of the American Chemical Society
|January 28, 2012
まとめ
コインメタルジメチルメタラート, [CH(3) MCH(3) ](-) (M = Cu, Ag, Au),アルリル置換における反応性は著しく異なっている. オーガノキュプレートは,これらの反応に優れているが,銀と金の類型とは異なり,反応機構が異なっている.
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
- コンピューティング・ケミストリー
背景:
- 銅媒介のアリル置換反応は,確立された合成ツールです.
- 銀と金を含む類似した反応は,ほとんど研究されていない.
- 機械的な違いを理解することは,合成開発にとって極めて重要です.
研究 の 目的:
- コインメタルジメチルメタラート ([CH(3) MCH(3) ](-),M = Cu, Ag, Au) のガス相反応性をアリルイオジドで調べる.
- 観察された反応性傾向に起因する根本的な反応機構を解明する.
- アリル基置換におけるオルガノキュプラートの優れた性能を説明するために.
主な方法:
- 熱に近い条件下でイオントラップ質量スペクトロメーターを使用して研究されたガス相反応.
- B3LYP/def2-QZVP//B3LYP/SDD6-31+G(d) 理論レベルを用いた電子構造の計算を行った.
- 4つの異なる反応機構の評価:S(N) 2,S(N) 2',M(III) η(3) -アリル経由による酸化添加/還元除去 (OA/RE),およびM(III) η(1) -アリル中間体経由によるOA/RE.
主要な成果:
- オーガノキュプレート ([CH(3) CuCH(3) ](-)) は,重要な反応性 (効率6.6%) を示し,クロスカップリングおよびホモカップリング製品を生成します.
- オーガノシルバー ([CH(3) AgCH(3) ](-)) とオーガノゴールド ([CH(3) AuCH(3) ](-)) アナログは,実質的に低い反応性と異なる製品分布を示しています.
- 計算分析により,明確なメカニズムが明らかになった:OA/RE経路は銅に優勢で,S(N) 2は銀に優勢で,C−C結合は金には有効ではない.
結論:
- この研究は,銀と金と比較して,アルリック置換反応におけるオルガノキュプラートの優れた有効性のメカニズム的根拠を強調しています.
- 反応経路は金属に依存し,銅は酸化添加/還元除去を好み,銀はS(N) 2メカニズムを好む.
- 金は,運動的に有効なC−C結合経路を示さないので,ヨウ化物と安定したAu (III) 複合体のみを形成する.
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