BH3の触媒量によって可能になったSi-B機能群交換反応:範囲,メカニズム,および適用
Jiong Zhang1,2, Rui Wei3, Chunping Ren1
1State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, Lanzhou 730000, P. R. China.
Journal of the American Chemical Society
|July 6, 2023
まとめ
この研究は,BH3によって触媒化された水素シランの最初のシリコン-ボロン機能群交換反応を導入する. 重要なシリコン化合物の合成を可能にします
科学分野:
- オルガノシリコン化学
- ボロン化学
- カタリシス
背景:
- 単一ボンド変換を含む機能グループ交換は,合成的に困難です.
- 既存の方法は,Si-H結合と比較してC-Si結合を裂くのが困難であるため,ヒドロシランと戦っています.
研究 の 目的:
- ハイドロシランに対する最初の触媒Si-B機能群交換反応を開発する.
- この新しい方法論の範囲と限界を調べる
- ゲルマニウム-ボロン交換とデポリメリゼーションを含む関連変換を調査する.
主な方法:
- ハイドロシランとヒドロボラン間のSi-B機能群交換反応の触媒としてBH3を活用した.
- 反応メカニズムを解明するために制御実験と密度関数理論 (DFT) を採用した.
- 様々なシリコン前駆体 (クロロシラン,シロキサンなど) の使用を調査した. そして水酸化反応を調査した.
主要な成果:
- アリルおよびアルキルヒドロシランおよびヒドロボランの幅広いSi-B機能群交換反応を初めて成功裏に実証した (115例).
- 連続したC-Si/B-HとC-B/B-H σ-結合の転移を含む反応経路を特定した.
- Si-BとGe-Bの機能的グループ交換,ポリシランの脱ポリメリゼーション,メチルシランの再生,アルケンの選択的水酸化を達成した.
結論:
- ハイドロシランにおけるSi-B機能群交換のための新しく汎用的な触媒方法が確立された.
- この方法論は,幅広い機能群の許容性と,様々なシリコンを含む分子へのアクセスを提供します.
- 拡張された応用には,Ge-B交換,デポリメリゼーション,および容易に入手可能な代用物質を用いた効率的な水酸化反応が含まれます.
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