Ca-FeまたはYb-Fe結合を含むヘテロメタリック複合体: [M{CpFe(CO) 2}2(THF) 3 2 (M = CaまたはYb) の合成および分子および電子構造
Matthew P Blake1, Nikolas Kaltsoyannis, Philip Mountford
1Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK.
Journal of the American Chemical Society
|September 6, 2011
まとめ
重アルカリ土と希土金属は,鉄複合体との直接的な金属対金属結合を形成する. イテルビウムと鉄の結合は,カルシウムと鉄の結合よりも短く,強く,マグネシウム化合物とは異なる.
科学分野:
- オーガノメタリック化学
- 無機化学 無機化学とは
- 固体化学 固体化学
背景:
- 新しい金属対金属結合の合成と特徴づけは,化学結合の理解に不可欠です.
- 重アルカリ性土壌金属と二価稀土金属の有機金属化合物との反応性を調査することで,それらの電子特性についての洞察が得られます.
研究 の 目的:
- カルシウムまたはイテルビウムと鉄の間の直接的な金属結合を特徴とする新しい化合物を合成し,特徴づけること.
- カルシウム-鉄,イテルビウム-鉄結合の結合特性と構造特性を比較する.
- マグネシウムの反応を同じ鉄前駆体と調査し,結果を比較する.
主な方法:
- アマルガム反応による金属結合化合物の合成.
- 構造的決定のための単結晶X線 difraktion.
- 密度関数理論 (DFT) の計算は,ジーグラー=ラウク,分子軌道,分子内の原子の分析を含む.
主要な成果:
- 同構造化合物[MFp (p) 2 (p) THF (p) 3 (p) 3 (p) 2) ] (M = Ca または Yb) が合成され,直接のM-Fe結合 (Ca-Fe: 3.0185 (p) 6) Å,Yb-Fe: 2.9892 (p) 4) Å) が示されました.
- DFTの計算は,Yb-Feの距離が短くなったことを確認し,主に静電M-Fe結合を示した.
- Yb-Fe結合はCa-Fe結合よりも高い相互作用エネルギーと結合臨界点電子密度を示した.
- マグネシウムは,直接のMg-Fe結合なしにMgFpp{2}{3}{4}を形成するために反応した.
結論:
- Ca/Ybと鉄の間の直接的な金属対金属結合は達成可能であり,Yb-Fe結合はCa-Fe結合よりも強く,短くなります.
- M-Fe結合は主に静電性であり,計算分析によってサポートされています.
- マグネシウムは異なる反応性を示し,直接的な金属対金属結合の代わりにO結合複合体を形成します.
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