一个单键结合的内体金属烯衍生物:La@C82CBr(COOC2H5)
Lai Feng1, Tsukasa Nakahodo, Takatsugu Wakahara
1Center for Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba 305-8577, Japan.
Journal of the American Chemical Society
|December 8, 2005
概括
研究人员合成了一种新的Bingel单添加物,即填充的富勒伦La@C82. 与典型的附加物不同,它具有将功能组连接到富勒烯的单一键,揭示了封闭的外结构.
科学领域:
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
背景情况:
- 富勒烯是具有独特电子性质的碳异构体.
- 宾格尔 - 希尔施反应是功能化富勒的一个常见方法.
- 像La@C82这样的内分体富勒伦,封装原子,改变它们的性质.
研究的目的:
- 为了合成和表征一个新的Bingel monoadduct的La@C82.
- 调查新添加物的结构和电子特性.
- 为了阐明La@C82单吸管的形成机制.
主要方法:
- 宾格尔 - 希尔施反应使用二甲基马酸盐和DBU.
- 核磁共振 (NMR) 谱学用于结构分析.
- 用X射线晶体学进行最终的结构确定.
- 计算计算以了解电子结构和机制.
主要成果:
- 成功合成了一种新的Bingel La@C82单添加物,命名为mono-A.
- 结构分析显示,马隆酸盐组与富勒烯之间存在独特的单键链接.
- 这与通常在空的富勒伦的添加物中形成的环旋环显著不同.
- 光谱和计算研究证实了单一-A的封闭外电子结构.
结论:
- 单一键 adduct 的形成是 La@C82 功能化的新奇结果.
- 单一-A的封闭外性质表明与开放外的富勒伦 adducts 相比,它具有明显的反应性.
- 了解形成机制可以让我们了解控制 fullerene 功能化的方法.
相关概念视频
02:37Metallic Solids
Metallic solids such as crystals of copper, aluminum, and iron are formed by metal atoms. The structure of metallic crystals is often described as a uniform distribution of atomic nuclei within a “sea” of delocalized electrons. The atoms within such a metallic solid are held together by a unique force known as metallic bonding that gives rise to many useful and varied bulk properties.
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
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...
02:34Structural Isomerism
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
01:23Properties of Organometallic Compounds
Organometallic compounds are compounds that contain a carbon–metal bond. Carbon belongs to an organyl group like alkyl, aryl, allyl, or benzyl groups. The metal can be from Group I or Group II of the periodic table, a transition metal, or a semimetal.
01:18β-Dicarbonyl Compounds via Crossed Claisen Condensations
Crossed Claisen condensations are base-promoted reactions between two different ester molecules producing β-dicarbonyl compounds. The reaction involving esters, with both containing α hydrogen, results in a mixture of four different products that are difficult to isolate. This reduces the synthetic utility of the reaction.
01:10C–C Bond Formation: Aldol Condensation Overview
Aldol condensation is an important route in synthetic organic chemistry used to generate a new carbon–carbon bond under basic or acidic conditions. The aldol condensation reaction presented in Figure 1 constitutes an aldol addition reaction followed by the dehydration process.