1,3-ダイエンのレジオとダイアステロセレクティブ鉄触媒 [4+4]-サイクル添加
C Rose Kennedy1, Hongyu Zhong1, Rachel L Macaulay1
1Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , United States.
Journal of the American Chemical Society
|May 8, 2019
まとめ
この研究は,ダイエンの効率的な [4+4]-サイクロディメリゼーションとサイクロアディションのための新しい鉄触媒を導入する. これらの触媒は立体同位体形成を制御し,大規模に有効です.
科学分野:
- 有機金属化学
- キャタリシス
- 有機合成
背景:
- 1,3-ダイエンの [4+4]-サイクロディメリゼーションとサイクロアディションは,有機合成における重要な反応である.
- これらの変化のための効率的で選択的な触媒の開発は,依然として重要な課題です.
- 鉄の複合体は貴重金属の触媒に代わる 有望で地球に豊富に存在するものです
研究 の 目的:
- モノ置換された1,3-ダイエンの [4+4]-サイクロダイメリゼーションおよび分子間クロス [4+4]-サイクロアディションのための単成分鉄前触媒を開発する.
- サイクロオクタディエンの産物の形成において,高い地域選択性およびダイアステロ選択性を達成する.
- 特定のダイアステロエーマー (cis または trans) に触媒制御されたアクセスを可能にする.
主な方法:
- 単一成分鉄前触媒の合成と特徴付け
- [4+4]-サイクロディメリゼーションおよびクロス[4+4]-サイクロアディション反応における触媒の適用.
- 単結晶X線 difraktion,Mößbauer光譜,磁気測定,およびDFT計算を含む構造とスペクトル分析.
- 運動分析,同位体効果研究,および現地スペクトロスコーピーを用いた機械的調査.
主要な成果:
- シクロオクタディエンの産物の形成において,高い地域選択性が達成された.
- 触媒制御は,シス-またはトランス-ダイアステロエーマーを4-置換ダイエンで選択的に合成することを許可した.
- 反応は一般的な有機機能群と互換性があり,マルチグラム量 (> 100g) にスケーラブルであった.
- 特徴付けにより,リガンドラジカルアニオンと結合した高スピン鉄 (I) センターを持つ触媒的に関連するS=1鉄複合体が見つかりました.
- ダイエンの酸化サイクルを伴う経路をメカニズム研究が支持し,選択性を決定した.
結論:
- 単一成分鉄前触媒は,効率的かつ選択的な [4+4]-サイクロディメリゼーションと1,3-ダイエンのサイクル添加を可能にします.
- 開発された触媒は,特定のダイアステレオマーへの触媒制御されたアクセスを含む,地域とダイアステレオ選択性の正確な制御を提供します.
- この発見は,鉄触媒によるダイエンのサイクル添加メカニズムに関する貴重な洞察を提供し,有機合成における実用的な応用への道を開きます.
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