香港中文大学缪谦团队通过Scholl反应合成锯齿形碳纳米带。相关研究成果于2021年2月18日发表在国际知名学术期刊《德国应用化学》。

锯齿形碳纳米带是有机合成领域长期以来备受追捧的目标。

该文中，研究人员开发了设计和合成前所未有的锯齿形碳纳米带的新策略，其（n，0）单壁碳纳米管（n=16或24）展开晶格中呈现六边形的波浪状排列。这些锯齿形碳纳米带的前驱体是杂化环芳基低聚物，由间苯撑和2,6萘撑以及对苯撑单元组成。这些环状芳基低聚物的Scholl反应在萘单元的α-位置选择性地形成多个碳-碳键，从而形成相应的锯齿状碳纳米带。

通过荧光光谱监测，其中一条纳米带在甲苯溶液中与C60结合，结合常数高达（6.6±1.1）×10⁶M1。结合线性回归分析和假设的同向键合反应的计算研究表明，这些锯齿形纳米带的应变范围为67.5至69.6 kcal/mol，这些纳米带的成功合成证明了Scholl反应合成多环芳烃的能力和效率。

附：英文原文

Title: Synthesis of Zigzag Carbon Nanobelts through Scholl Reactions

Author: Zeming Xia, Sai Ho Pun, Han Chen, Qian Miao

Issue&Volume: 2021-02-18

Abstract: Zigzag carbon nanobelts are a long‐sought‐after target for organic synthesis. Herein we report new strategies for designing and synthesizing unprecedented zigzag carbon nanobelts, which present a wave‐like arrangement of hexagons in the unrolled lattice of (n,0) single wall carbon nanotubes (n = 16 or 24). The precursors of these zigzag carbon nanobelts are hybrid cyclic arylene oligomers consisting of  meta  ‐phenylene and 2,6‐naphthalenylene as well as  para  ‐phenylene units. The Scholl reactions of these cyclic arylene oligomers form multiple carbon‐carbon bonds selectively at the α‐positions of naphthalene units resulting in the corresponding zigzag carbon nanobelts. As monitored with fluorescence spectroscopy, one of these nanobelts binds C  60  with an association constant as high as (6.6±1.1) × 10  6   M  1  in the solution in toluene. Computational studies combining linear regression analysis and hypothetical homodesmotic reactions reveal that these zigzag nanobelts have strain in the range of 67.5 to 69.6 kcal/mol, and the ladderization step through Scholl reactions is accompanied by increase of strain as large as 69.6 kcal/mol. The successful synthesis of these nanobelts demonstrates the powerfulness and efficiency of Scholl reactions in synthesizing strained polycyclic aromatics.

DOI: 10.1002/anie.202100343

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202100343