テトラアリル二ボランの制御された還元によるB-B結合の形成 ((6)
Thomas Kaese1, Alexander Hübner1, Michael Bolte1
1Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt , Max-von-Laue-Straße 7, D-60438 Frankfurt am Main, Germany.
Journal of the American Chemical Society
|April 26, 2016
まとめ
ディメリック・アリル (hydro) ボランは,ボロン添加グラフェンの前駆体として機能する. LiNaph/THFまたはKC8のような反応剤との還元結合は,リング収縮型および水素ブリッジ型を含む様々なボロン含有構造を生成する.
科学分野:
- 有機金属化学
- 材料科学
- ボロン化学
背景:
- ディメリックアリル (hydro) ボランは,新しいボロン含有化合物を合成するための多機能な前駆物質である.
- 還元性B-Bカップリングは,グラフェン誘導体を含むボロン-炭素材料を作成するための経路を提供します.
- 代替剤の再配分と過剰還元を理解することは,反応結果を制御するために極めて重要です.
研究 の 目的:
- 特定の二次アリル ((水素) ボラン,1,2:1,2-ビス ((4,4'-ディ-テル-ブチル-2,2'-ビフェニリレン) ディボランの還元性B-B結合を調査する.
- 異なる還元剤 (LiNaph/THFとKC8) とそのステキオメトリが反応製品に及ぼす影響を調査する.
- 再配列された多循環性芳香炭水化物を含む,結果として生じるボロン含有構造の特徴を述べる.
主な方法:
- テトラヒドロフラン (THF) のリチウムナフタレニド (LiNaph) を使って2電子還元.
- カリウムグラフィート (KC8) を用いた還元と,その後の水素抽出反応.
- 多核核磁気共振 (NMR) スペクトロスコーピーとX線結晶学を用いて合成されたすべての製品の特徴づけ.
主要な成果:
- ディボランのLiNaph/THF還元は,過剰還元によって再配列された製品 (Li2[6],Li2[7]) と二重ボロンドーピングされたディベンゾ[g,p]クリゼン (Li2[1]) を生成する.
- KC8の還元により,トランス-HB-BHコアを持つダイヒドロディベンゾ[g,p]クリゼン (K2[5]) が生成される.
- K2からの水素抽出[5]またはKC8による直接還元により,単一の水素原子 (K[8]) によって橋渡されたB-B結合が得られる.
結論:
- 二次性アリル・ヒドロボランの還元結合は,複雑なボロン含有構造への実行可能な経路である.
- 還元剤のステキオメトリーは,還元と再配置の範囲を決定的に制御します.
- この研究は,新しいボロン添加多環芳香炭化水素と水素ブリッジディボランの合成と構造的特徴を示す.
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