ルテニウムで触媒化されたアジド-アルキンサイクル添加:範囲とメカニズム
Brant C Boren1, Sridhar Narayan, Lars K Rasmussen
1Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Journal of the American Chemical Society
|June 24, 2008
まとめ
ルテニウム (II) 複合体は,アジド-アルキンサイクロアディションを効率的に触媒化し,1,5-非置換および完全置換の1,2,3-トリアゾールを生成します. ルテニウム触媒によるアジドアルキンサイクル添加 (RuAAC) メカニズムには,酸化結合と還元性除去が含まれています.
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
- カタリシス カタリシス カタリシス
背景:
- ルテニウム複合体は,有機変換における汎用的な触媒である.
- アジド-アルキンサイクロアディションは,窒素を含むヘテロサイクルの合成に不可欠です.
研究 の 目的:
- アジド-アルキンサイクロアディションの触媒としてのルテニウム (II) 複合体を評価する.
- ルテニウム触媒によるアジド-アルキンサイクル添加 (RuAAC) の範囲と限界を調査する.
主な方法:
- 様々な [Cp*RuCl]複合体のスクリーニング,Cp*RuCl(PPh3) 2,Cp*RuCl(COD,Cp*RuCl(NBDを含む.
- 初次,二次,三次アジドと終末および内部アルキンの反応.
- 密度関数理論 (DFT) の計算を用いたメカニズム調査.
主要な成果:
- Cp*RuCl (PPh3) 2とCp*RuCl (COD) は,高い触媒活性を示した.
- 主要・次要アジドおよび末端アルキンから1,5-非置換の1,2,3-トリアゾールの選択合成.
- 内部アルキンを用いて完全に置換された1,2,3-トリアゾールへのアクセス.
結論:
- ルテニウム (II) 複合体は,様々なアジド-アルキンサイクロアディションの効果的な触媒である.
- RuAAC反応は,提案された酸化結合と還元性除去機構を介して進行します.
- DFTの計算は,レート決定として還元的な排除を識別して,提案されたメカニズムをサポートします.
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