モノメアアリルパラジウム ((II) ハリド複合物からアリルハリドの直接観察された還元性除去
1Department of Chemistry, Yale University, P.O. Box 208107, New Haven, CT 06520-8107, USA.
Journal of the American Chemical Society
|November 13, 2003
まとめ
パラジウムのアリルハリド複合体 (II) は,還元的な除去をします. 熱力学ではなくハリドの電子性質が,アリル塩化物,ブロミド,ヨウ酸化物の還元性除去率を決定する.
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
- 反応メカニズム 反応メカニズム
背景:
- モノメール型,3座標のアリルパラジウム ((II) ハリド複合体は,様々な触媒過程における重要な中間物質である.
- パラジウム複合体からアリルハリドを還元的に除去すると,ハロアレンとPd(0) が形成されます.
研究 の 目的:
- パラジウム (II) 複合物からアリルハリド (塩化物,ブロミド,ヨウ酸化物) の還元性除去を調査する.
- これらの反応の速度と熱力学を制御する要因を決定する.
主な方法:
- モノメアアリルパラジウム (((II) ハリド複合体の合成とP (((t-Bu) 3リガンド.
- P(t-Bu) を加えたときの還元性除去の観察3.
- 5つのハロアレンによる還元性除去と酸化性添加のための均衡条件の確立.
主要な成果:
- アリル塩化物,ブロミド,ヨジドの還元性除去が観察されました.
- 還元性除去のための熱力学的好み:塩化物 > ブロミド > ヨウ化物.
- 還元性の除去のための動的速度: ブロミド > ヨウ化物 > クロリド.
- ハリドの電子特性,熱力学的な原動力ではなく,制御反応速度.
結論:
- ハリドリガンドの電子特性は,アリルパラジウム (II) 複合体における還元性除去率の主な決定因子である.
- メカニズム研究では,初期還元性除去後に P ((t-Bu) 3) を含む速度制限の調整ステップが示唆されています.
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