Giant Fullerene Polyelectrolytes Composed of C60 Building Blocks with an Octahedral Addition Pattern and Discovery of a New Cyclopropanation Reaction Involving Dibromomalonates
Giant Fullerene Polyelectrolytes Composed of C60 Building Blocks with an Octahedral Addition Pattern and Discovery of a New Cyclopropanation Reaction Involving Dibromomalonates
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DOI：
10.1002/chem.201203881
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发表时间：
2013-02-01
影响因子：
4.3
通讯作者：
Hirsch, Andreas
中科院分区：
文献类型：
--
作者：
Hoermann, Frank;Hirsch, Andreas
我们在这里报告的一个新的家庭的双，四，六，和heptafullerenes（原型IIV），它可以很容易地转换成非常水溶性的聚电解质与高达60个电荷位于其外围的简易合成访问。它们非常区域选择性的形成是基于使用C2 v-对称的pentakisadducts 3和hexakisadducts 2作为关键中间体。所有富勒烯部分纳入这些大分子结构涉及一个完整的或部分的八面体加成模式。三脚架形四富勒烯9a、B（II型）可累积多达30个正电荷或负电荷，分别极易溶于酸性水或碱性水。六富勒烯13 a，B（III型）是通过异恶唑啉富勒烯10，然后通过异恶唑啉基团的光解裂解合成的。巨大的七富勒烯1b（IV型）代表先前合成的七富勒烯1a的阴离子对应物，可以在定义的三维结构内在其外围存储多达60个负电荷。我们还发现了一个新的C60环丙烷化反应，涉及二溴丙二酸酯和1，8-二氮杂双环[5.4.0]十一碳-7-烯（DBU）。该反应甚至允许高度区域选择性地形成具有八面体加成模式的六加合物，而不需要用可逆结合的粘附剂如9，10-二甲基蒽（DMA）活化。
We report here on the facile synthetic access of a new family of bis-, tetra-, hexa-, and heptafullerenes (prototypes IIV), which can be easily converted into very water soluble polyelectrolytes with up to 60 charges located on their periphery. Their very regioselective formation is based on the use of C2v-symmetrical pentakisadducts 3 and hexakisadducts 2 as key intermediates. All fullerene moieties incorporated in these macromolecular structures involve a complete or partial octahedral addition pattern. Tripod-shaped tetrafullerenes 9a,b (type II), which can accumulate up to thirty positive or negative charges, are very soluble in acidic or basic water, respectively. Hexafullerenes 13a,b (type III) were synthesized via isoxazolinofullerenes 10 followed by photolytic cleavage of the isoxazoline group. The giant heptafullerene 1b (type IV) representing the anionic counterpart of the previously synthesized polyelectrolyte 1a can store up to 60 negative charges on its periphery within a defined three-dimensional structure. We also discovered a new cyclopropanation reaction of C60 involving dibromomalonates and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). This reaction allows even for the highly regioselective formation of hexakisadducts with an octahedral addition pattern without requiring activation with reversibly binding addends such as 9,10-dimethylanthracene (DMA).