カーボニル基を利用して分子間ロジウム触媒アルケンとアルキンの水酸化を制御する
Thomas J Coxon1, Maitane Fernández1, James Barwick-Silk1
1Department of Chemistry, Chemistry Research Laboratory, University of Oxford , Mansfield Road, Oxford OX1 3TA, U.K.
Journal of the American Chemical Society
|July 18, 2017
まとめ
ロジウム触媒による水酸化反応は,すぐに利用可能なβ-カルボニル置換アルデヒドを有効な1,3-二カルボニル化合物へと効率的に変換する. この方法は,アルケンの地域選択制御を含む様々なアルケンとアルキンの高い生産性と選択性を提供します.
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- 水酸化は炭素結合形成の重要な反応である.
- 水酸化のための効率的な触媒システムの開発は,活発な研究分野です.
- β-カルボニル置換アルデヒドは,多用途の合成前駆体である.
研究 の 目的:
- ロジウム触媒化水酸化におけるβ-カルボニル置換アルデヒドの有用性を調査する.
- この変換のために効率的で選択的な触媒システムを開発する.
- アルキン水酸化における地域選択性制御を調査する.
主な方法:
- ビスフォスフィンリガンドを伴うカチオンロジウム触媒を用いる.
- 基質としてβ-アミド,β-エステル,およびβ-ケトアルデヒドを使用する.
- 様々なアルケンやアルキンと反応するアルデヒド.
- アンパフォスのリガンドがアルキン水酸化地域選択性への影響を調査する.
主要な成果:
- β-カルボニル置換アルデヒドをアルケンとアルキンで水酸化した.
- 1,3-ジカルボニル製品の高収量と優れた選択性
- アルデヒドと不飽和のパートナーの両方に幅広い基板範囲があります.
- アンパフォスのリガンドを用いたアルキンの水酸化のための地域選択性スイッチの実証.
- 構造データとメカニズムの洞察が提供されました.
結論:
- β-カルボニル置換アルデヒドは,Rh触媒化水酸化のための例外的な基質である.
- 開発された触媒システムは,合成的に有用な1,3-ジカルボニル化合物への効率的なアクセスを提供します.
- アルキンの線形同位体と分岐性同位体の地域選択合成は可能である.
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