Angew：Scholl反应选择性合成螺环与螺旋纳米石墨烯

Scholl氧化已成为自下而上合成分子纳米石墨烯的一个重要反应。在此，作者描述了由起始衬底(1 a, b)上的电子效应控制的Scholl反应 。在Scholl条件下，蒽基聚苯导致螺纳米石墨烯。相反，缺电子的anthracene衬底提供了由两个正交dibenzo[fg,ij]phenanthro-[9,10,1,2,3-pqrst]pentaphene (DBPP)和octafluoroanthracene核连接而形成的螺旋排列的分子纳米石墨烯。密度泛函理论（DFT）计算预测，电子效应要么控制螺环的第一次形成和随后的Scholl反应以形成螺环纳米石墨烯2，要么通过预期的脱氢反应仅形成螺旋纳米石墨烯3。用单晶X射线衍射分析了四种新螺环化合物（syn 2, syn 9, anti 9 and syn 10）的晶体结构。新分子纳米石墨烯3的光物理特性显示出显著的双荧光发射。

示意图1 Scholl oxidation of 1 leads to the formation of spironanographene syn 2 or helical nanographene 3 depending on the electronic features of the starting polyphenylene (1 a or 1 b).

示意图2 Synthetic scheme for the synthesis of 1 a and further Scholl reaction.

示意图3 Synthetic scheme for the preparation of nanographene 3

图1 Molecular structure of the compounds solved by single crystal X-ray diffraction, where hydrogen atoms have been omitted for clarity; a) syn 9, b) anti 9, c) syn 10, d) syn 2.

图2 Intramolecular π-π interactions in syn 2.

图3 Computed reaction profiles for the Scholl and spiro-cyclization reactions involving anthracene derivative 1 a-M.

图4 Normalized absorption (dark green) and emission (clear green) spectra of syn 2 recorded in hexane at room temperature

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来源：Patricia Izquierdo-García, Dr. Jesús M. Fernández-García, Dr. Josefina Perles, Dr. Israel Fernández, Prof. Dr. Nazario Martín，Electronic Control of the Scholl Reaction: Selective Synthesis of Spiro vs Helical Nanographenes，Angew. Chem. Int. Ed. 2023, 62, e202215655，https://doi.org/10.1002/anie.202215655