イリジウム触媒による非活性化アルキルC−H結合のヒドロシリル誘導型ボリレーション
Matthew A Larsen1, Seung Hwan Cho1, John Hartwig1
1Department of Chemistry, University of California , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|January 9, 2016
まとめ
イリジウム触媒によるボリレーションにより,アルキルC−H結合が選択的に機能する. この方法は,多用途のアルキルボロナートエステルを生成し,高いサイトとステレオ選択性を持つ多様な下流化学変換を可能にします.
科学分野:
- 有機金属化学
- カタリシス
- 合成有機化学
背景:
- C−H結合の機能化は,効率的な合成に不可欠である.
- 誘導グループ戦略は,触媒反応におけるサイト選択性を高めます.
- ボロナートエステルは有価な合成中間物質である.
研究 の 目的:
- アルキルC−H結合の部位選択型ボリル化のためのイリジウム触媒法を開発する.
- C−H ボリル化におけるヒドロシリル基の指向効果を調査する.
- 合成されたアルキルボロナートエステルの有用性を調査する.
主な方法:
- イリジウム触媒によるC-H活性化と,ヒドロシリル誘導基を用いたボリル化.
- 主要および二次アルキルC-H結合の選択的機能化
- 合成されたアルキルボロナートエステルの後の変換.
主要な成果:
- 主要なC-H結合ガンマとヒドロシリル群でのボリル化のための高いサイト選択性.
- 主要なC-H結合が存在しないとき,二次的C-H結合ガンマからヒドロシリル群への選択的ボリレーション.
- 二次性C−H結合のボリル化で高いダイアステロ選択性が見られた.
- 製品のC-BとC-Si結合における選択的変異の実証 (アミネーション,酸化,アリレーション).
結論:
- イリジウム触媒によるボリレーションは,アルキルC-H結合のサイト選択的機能化のための強力なツールを提供します.
- ヒドロシリルグループは,高選択性のある特定の位置にボリレーションを効果的に導きます.
- 生成されたアルキルボロナートエステルは,さらなる合成処理のための多用途な構成要素である.
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