アシルゲルマン: 発光剤と,G-中心のラジカルの源である. 彼らの反応性についての洞察を得ました
Dmytro Neshchadin1, Arnulf Rosspeintner, Markus Griesser
1Institute of Physical and Theoretical Chemistry and §Institute of Chemistry and Technology of Materials, Graz University of Technology , Stremayrgasse 9, 8010 Graz, Austria.
Journal of the American Chemical Society
|October 17, 2013
まとめ
Dibenzoyldiethylgermaneは,光始動剤として作用し,アクリラートと急速に反応する生殖基を形成します. これらの反応は,類比よりも速く,Ge-O結合を含むオリゴーマーを生成します.
科学分野:
- 有機金属化学 有機金属化学
- フォトケミストリー フォトケミストリー
- ポリマーサイエンスの科学
背景:
- アシルゲルマンは,ポリメリゼーションプロセスにおけるフォトイニシアターとしての可能性が認められています.
- 光刺激下でのアシルゲルマンの反応機構を理解することは,その応用を最適化するために極めて重要です.
研究 の 目的:
- 光刺激によるディベンゾイルジエチルゲルマンの反応経路を解明する.
- フォトイニシエーション過程で形成される一時的な中間物質と最終製品を特徴付ける.
- ゲルミールラジカルの反応性を他の関連性のあるラジカル種と比較する.
主な方法:
- フェムトとナノ秒の臨時吸収スペクトロスコーピー.
- 時間分解の電子パラマグネティック共振 (EPR) スペクトロスコーピー.
- 光化学的に誘発されたダイナミックな核極化 (CIDNP).
- 密度関数理論 (DFT) による計算.
- ガス染色体-質量スペクトロメトリー (GC-MS).
- 液体クロマトグラフィー - 核磁気共振 (LC-NMR). 液体クロマトグラフィー - 核磁気共振 (LC-NMR).
主要な成果:
- ディベンゾイルジエチルゲルマン (Dibenzoyldiethylgermane) は,光刺激時にそのトリプレート状態を通じてベンゾイルジエチルゲルミル基 (G•) を形成する.
- G•ラジカルは,ナノ秒のスケールで再結合または水素転送反応を経験します.
- ラジカルG•は,ブチルアクリラートで素早く反応し,リン基のラジカルを上回る.
- ゲルミールとベンゾイルラジカルのフォローアップ反応により,Ge-O結合を含むオリゴーマーが形成されます.
結論:
- この研究は,dibenzoyldiethylgermaneを含むフォトイニシエーションプロセスに関する詳細なメカニズム的洞察を提供します.
- ゲルミル基の観測された高い反応性は,効率的な光発起体としてのその可能性を強調しています.
- Ge-O結合を含む製品の形成は,アシルゲルマンゼによって媒介されるユニークなポリメリゼーション経路を示唆しています.
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