エンドヘドラル型二金属フルルレンの地域選択的二機能化,La2@C80:極端のLa-La距離
Midori O Ishitsuka1, Shogo Sano, Haruka Enoki
1TARA Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan.
Journal of the American Chemical Society
|April 19, 2011
まとめ
カーベン添加を用いたランタンで満たされたフルレレン (La(2)@C(80) の二次機能化により,ランタンと金属の距離が伸びた. この研究は,これらの新種のメタルフルレレン誘導体における構造的および電子的変化を詳細に説明します.
科学分野:
- 超分子化学 超分子化学
- ナノ材料科学 ナノ材料科学
- 有機金属化学 有機金属化学
背景:
- 内分型金属フルフルレン (EMF) は,ユニークな電子的および構造的特性を有しています.
- ランタンベースのEMFは,例えばLa(2)@C(80) のように,その潜在的なアプリケーションのために興味があります.
研究 の 目的:
- カーベンの添加を用いて,La(2)@C(80) 末端型金属フラーレンの二次機能化を調査する.
- その結果得られたアダクトを特徴付け,構造変化,特にランタン-ランタン距離を分析する.
主な方法:
- La(2)@C(80) に対するカルベンの添加反応.
- スペクトロスコーピカル特徴付け (例えば,NMR,質量スペクトロメトリー).
- 単一結晶X線微分分析. 単一結晶X線微分分析. 単一結晶X線微分分析. 単一結晶X線微分分析. 単一結晶X線微分分析. 単一結晶X線微分分析. 単一結晶X線微分分析.
- 密度関数理論 (DFT) による計算.
主要な成果:
- La(2)@C(80) の成功した二次機能化は,カルベン添加で達成されました.
- X線結晶学により,カーベンの添加が,C(80) の6.6結合の交点で発生し,リングの割れ目を誘発することが明らかになった.
- ランタン原子はスパイロ炭素とコリネラルに配置されていることが判明しました.
- バイサドクトでは,原始のEMFおよび他の誘導体と比較して,ララ距離の有意な延長が観察されました.
- DFTの計算は,観測された金属の位置を確認した.
結論:
- カーベンの二次機能化は,La(2)@C(80) の構造を変更するための経路を提供します.
- 機能化のプロセスは,ケージの変形や金属対金属の距離の変化を含む,重要な構造変化につながります.
- この研究は,共電性機能化を通じて,EMFの特性の調節性を実証しています.
さらに関連する動画
関連する概念動画
02:34Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
The rate of acid-catalyzed hydration of alkenes depends on the alkene's structure, as the presence of alkyl substituents at the double bond can significantly influence the rate.
02:42Valence Bond Theory
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
02:36Regioselectivity and Stereochemistry of Hydroboration
A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
02:51Metal-Ligand Bonds
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
![[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2Ffiles%2Fmedia%2Fscience-education%2Fscience-education-thumbs%2F12417.jpg&w=3840&q=75)
01:16[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.
02:58Crystal Field Theory - Octahedral Complexes
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...