マイケル受容体を用いた二次および三次アルキル塩化物のチア触媒による根性アルキル化
Xiangyu Wu1, Wei Hao1, Ke-Yin Ye1
1Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853 , United States.
Journal of the American Chemical Society
|October 11, 2018
まとめ
この研究では,活性化されていないアルキル塩化物を用いて炭素-炭素結合を形成するための新しいチタン触媒法が導入されています. この新しいアプローチは,電子欠乏性アルケンの二次および三次アルキル塩化物の根本的添加を可能にします.
科学分野:
- 合成有機化学
- 有機金属化学
- ラジカル・ケミストリー
背景:
- アルキル塩化物は有機合成における多用途な機能群である.
- 非活性化アルキル塩化物,特に三次性アルキル塩化物,をC−C結合形成のために移行金属触媒で活性化することは困難である.
研究 の 目的:
- 電子欠乏アルケンの二次 (2°) と三次 (3°) アルキル塩化物の激素添加のための新しいチタン触媒法を開発する.
- 活性化されていないアルキル塩化物をC−C結合形成に巻き込むという課題を克服する.
主な方法:
- 基質加減反応にチタン (III) 触媒を使用した.
- C-Cl結合の活性化メカニズムを調査した.
- ルイス酸による電子移転を含む触媒サイクルを提案した.
主要な成果:
- 電子欠乏アルケンの2°および3°アルキル塩化物のTi (III) 誘導基添加を成功裏に実証した.
- 機械学的研究は,Ti (III) 媒介の塩素原子抽出によるC-Cl結合の内球活性化を示した.
- 電子移転プロセスを通してTi(IV) 前駆体から活性Ti(III) 触媒の生成を特定した.
結論:
- 開発された方法は,挑戦的なアルキル塩化物基板を使用してC-C結合形成のための新しい経路を提供します.
- この発見は,チタン触媒による急性反応のメカニズムに洞察を与えてくれます.
- この研究は,アルキル塩化物の移行金属触媒機能化の範囲を拡大する.
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