アルカリ土移行金属結合の限界を測る:実験と計算による研究
Matthew P Blake1, Nikolas Kaltsoyannis2, Philip Mountford1
1Chemistry Research Laboratory, Department of Chemistry, University of Oxford , Mansfield Road, Oxford OX1 3TA, United Kingdom.
Journal of the American Chemical Society
|September 5, 2015
まとめ
コバルトカルボニル複合体による新しいアルカリ土金属 (Ae) とランタニド (Ln) 化合物が合成された. これらの金属とコバルトの結合相互作用は大きく変化し,化合物の構造と安定性に影響を与えます.
科学分野:
- 有機金属化学
- 協調化学
- 材料科学
背景:
- アルカリ土金属 (Ae) とランタノイド (Ln) は,様々な化学用途において重要である.
- 有機金属複合体の金属結合の理解は,新しい材料の設計に不可欠です.
- 以前の研究では金属-リガンドの相互作用が調査されているが,Ae-TMとLn-TMの結合についてはさらなる調査が必要である.
研究 の 目的:
- トランジションメタルカルボニル断片を用いた新しい Ae と Ln コンプレクスを合成し,特徴づけること.
- アルカリ土/ランタニド金属と移行金属 (TM) の間の結合の性質を調査する.
- 金属と金属の結合に対する金属の電荷比とリガンド効果の影響を調査する.
主な方法:
- Mg,Ca,Sr,Ba,Yb,Eu,Sm-水銀アマルガムを用いた移行金属カルボニル複合体の減少
- 新規のAeおよびLn有機金属化合物の合成と分離
- 拡散型NMRスペクトロスコーピーのような技術を用いた特徴付け.
- 密度関数理論 (DFT) とジグラー・ラウクエネルギー分解を含む計算分析.
主要な成果:
- [M{Co(CO) 3(PCy3) }2(THF) n]2型の新しい二次化合物が合成され,M = AeまたはLnであった.
- M-Co結合モードは,金属の電荷対サイズ比によって変化し,直接のM-Co結合からイソカルボニル結合 (η(1) とサイド・オン・コーディネーション (η(2) まで変化する.
- DFTの計算は,Ae-Coの相互作用エネルギーがグループ全体で減少していることを明らかにし,直接結合とCOリガンドの調整の間の競争を強調した.
結論:
- アルカリ土とランタニド金属の充電比は,移行金属カルボニルとの結合相互作用を大きく左右する.
- リガンドの選択,特に大量のPCy3リガンドは,溶解性を高め,金属と金属の相互作用エネルギーに影響を与えます.
- これらの金属結合の性質と強さに関する貴重な洞察を 計算手法で提供し,将来の合成研究に 役立つ.
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