二価M ((C ((SiHMe)) のルイス酸媒介のβ-ヒドリド抽象反応 (M = Ca, Yb) は,二価M ((C ((SiHMe)) の二価M ((C ((SiHMe)) の二価M ((C ((SiHMe)) の二価M ((C
KaKing Yan1, Brianna M Upton, Arkady Ellern
1Department of Chemistry and U.S. Department of Energy Ames Laboratory, Iowa State University, Ames, Iowa 50011-3111, USA.
Journal of the American Chemical Society
|October 3, 2009
まとめ
ベータ-アゴスティックなSiH群を持つカルシウムおよびイテルビウム化合物は,ルイス酸と水素抽象反応を示し,予期せぬ製品を形成し,有機金属化学におけるベータ除去経路を排除します.
科学分野:
- 有機金属化学 有機金属化学
- シリコン化学 シリコン化学
- 協調化化学について
背景:
- ベータアゴスティックなSiH群を特徴とする二価カルシウムとイテルビウム化合物を合成した.
- これらの化合物は,重要な水性特性を持つSiH結合を有しています.
- 以前の研究では,関連するシステムにおけるベータ除去経路の可能性が示唆されていた.
研究 の 目的:
- ルイス酸によるM(C(SiHMe(2)) ((3)) ((2)) THF(2) 化合物の反応性を調査する.
- 反応のメカニズムを明らかにし,特にβ除去と水素抽象を調査する.
- ボロンベースのルイス酸との反応で形成される産物を特徴付けるため.
主な方法:
- 二価カルシウムとイテルビウム複合体の合成と特徴付け.
- 構造的特徴を決定するために,光譜分析 (例えば,NMR) とX線結晶学.
- ルイス酸,特にB ((C ((6) F ((5)) ((3)) とBPh ((3) との反応を行い,その後に製品の分離と分析を行います.
主要な成果:
- 化合物M ((C ((SiHMe ((2)) ((3)) ((2) THF ((2)) はベータアゴスティックなSiH群を示す.
- ルイス酸B ((C ((6) F ((5)) ((3)) とBPh ((3) との反応は,主に水素抽出で, [HB ((C ((6) F ((5)) ((3)) ]または関連するアニオンを形成します.
- 1,3-disilacyclobutaneの形成は観察されましたが,ステキオメトリーおよび他の製品に基づいてβ除去の製品として除外されました.
結論:
- ベータ除去は,これらの特定のM ((C ((SiHMe ((2)) ((3)) ((2)) THF ((2)) 化合物にとって,水性SiH群とルイス酸性金属中心の存在にもかかわらず,実行可能な反応経路ではありません.
- ハイドリド抽出は,これらの化合物がルイス酸と相互作用するときに支配的な反応経路です.
- この研究は,シリコン-ヒドリド結合を持つ低座標金属複合体の反応性状況を明らかにしています.
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