Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan.
1] Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan [2] JST-ERATO, Itami Molecular Nanocarbon Project, Nagoya University, Chikusa, Nagoya 464-8602, Japan.
Nat Chem. 2015 Mar;7(3):227-33. doi: 10.1038/nchem.2174. Epub 2015 Jan 26.
Since its discovery in 1825, benzene has served as one of the most used and indispensable building blocks of chemical compounds, ranging from pharmaceuticals and agrochemicals to plastics and those used in organic electronic devices. Benzene has six hydrogen atoms that can each be replaced by different substituents, which means that the structural diversity of benzene derivatives is intrinsically extraordinary. The number of possible substituted benzenes from n different substituents is (2n + 2n(2) + 4n(3) + 3n(4) + n(6))/12. However, owing to a lack of general synthetic methods for making multisubstituted benzenes, this potentially huge structural diversity has not been fully exploited. Here, we describe a programmed synthesis of hexaarylbenzenes using C-H activation, cross-coupling and [4+2] cycloaddition reactions. The present method allows for the isolation and structure-property characterization of hexaarylbenzenes with distinctive aryl substituents at all positions for the first time. Moreover, the established protocol can be applied to the synthesis of tetraarylnaphthalenes and pentaarylpyridines.
自 1825 年被发现以来，苯一直是化学化合物中最常用和不可或缺的结构单元之一，从药物和农用化学品到塑料和有机电子设备中使用的材料都有苯的身影。苯有六个氢原子，每个氢原子都可以被不同的取代基取代，这意味着苯衍生物的结构多样性本质上是非常非凡的。由 n 个不同取代基组成的可能的取代苯的数量为(2n+2n(2)+4n(3)+3n(4)+n(6))/12。然而，由于缺乏用于合成多取代苯的通用合成方法，这种潜在的巨大结构多样性尚未得到充分利用。在这里，我们描述了使用 C-H 活化、交叉偶联和[4+2]环加成反应来合成六芳基苯的程序化方法。该方法首次允许分离和结构-性能表征所有位置都具有独特芳基取代基的六芳基苯。此外，所建立的方案可应用于四芳基萘和五芳基吡啶的合成。
