プラゼオジミウムの分子複合体における+IV酸化状態へのアクセス
Aurélien R Willauer1, Chad T Palumbo1, Farzaneh Fadaei-Tirani1
1Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
Journal of the American Chemical Society
|March 6, 2020
まとめ
研究者は安定したプラセオジウム ((IV)) 複合体を合成し,既知のランタニド ((IV)) 酸化状態をセリウムとテルビウムを超えて拡張した. この発見はランタナイド化学の 新しい道を開きます
科学分野:
- 無機化学
- ランタニド化学
- 酸化状態の化学
背景:
- ランタニド (Lanthanide) の酸化状態は稀であり,以前はセリウムとテルビウムのみが記録されていた.
- プラゼオジミウムは通常,+III酸化状態に存在する.
研究 の 目的:
- プラセオジミウムの+IV酸化状態へのアクセシビリティを調査する.
- 新しいプラセオジミウム (IV) 複合体を合成し,特徴づけること.
主な方法:
- プレセオジウム (III) 前駆体複合体の酸化.
- 生成されたプラゼオジミウム (IV) 複合体の分離と浄化.
- X線結晶学,紫外線可視光譜学,磁気計,循環電圧計,DFT計算を用いた特徴付け.
主要な成果:
- 安定したプラゼオジミウム複合体 [Pr(OSiPh3) 4 ((MeCN) 2) の合成に成功した.
- 構造,光譜,磁気,電気化学データは,Pr (IV) の酸化状態を確認した.
- 密度関数理論 (DFT) の計算が実験結果を支持した.
結論:
- +IV酸化状態は,プラゼオジミウムカチオンに利用可能である.
- この発見は,ランタニドの ((IV) 酸化状態の既知の範囲を拡大する.
- 合成されたプラセオジミウム (IV) 複合体は安定し,よく特徴づけられている.
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