Synthesis of Zigzag Carbon Nanobelts through Scholl Reactions

Abstract

Zigzag carbon nanobelts are al ong-sought-after target for organic synthesis.Herein we report new strategies for designing and synthesizing unprecedented zigzag carbon nanobelts,which present awave-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 metaphenylene and 2,6-naphthalenylene as well as para-phenylene units.T he Scholl reactions of these cyclic arylene oligomers form multiple carbon-carbon bonds selectively at the apositions of naphthalene units resulting in the corresponding zigzag carbon nanobelts.A sm onitored with fluorescence spectroscopy, one of these nanobelts binds C 60 with an association constant as high as (6.6 AE 1.1) 10 6 M À1 in the solution in toluene.C omputational 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 À1 ,a nd the ladderization step through Scholl reactions is accompanied by increase of strain as large as 69.6 kcal mol À1 .T he successful synthesis of these nanobelts demonstrates the powerfulness and efficiency of Scholl reactions in synthesizing strained polycyclic aromatics. Figure 1. (a) [n]Cyclacene and zigzag carbon nanobelts reported very recently;( b) structures of zigzag carbon nanobelts 1-3.

A Green Fluorescent Nitrogen‐Doped Aromatic Belt Containing a [6]Cycloparaphenylene Skeleton

“…[1] Although the construction of such kinds of conjugated belts underwent more than 60 years of efforts, a breakthrough was made with the synthesis of the first armchair carbon nanobelt in 2017. [2] Recently, Chi, [3] Itami, [4] and Miaos group [5] reported the successful synthesis of zig-zag conjugated nanobelts. [6] Meanwhile, along with the investigation of all-carbon conjugated nanobelts, some efforts focused on the incorporation of heteroatoms into the aforementioned belts were also explored to fulfill the construction of new class of CNTs with heterojunctions.…”

Electronic and structural properties of Möbius boron-nitride and carbon nanobelts

“…Povie et al made a breakthrough with the synthesis of carbon nanobelts (CNBs), whose simple structure in the form of a ring or belt generates two faces, one internal and one external, not convertible to each other [ 13 ]. Carbon nanobelts represent segments of single-walled carbon nanotubes containing a benzene ring cycle with p orbitals aligned in a plane [ 14 ]. Such behavior allows them to be classified as armchair, zigzag, or chiral nanoribbons according to the chirality index [ 14 , 15 ].…”

“…Carbon nanobelts represent segments of single-walled carbon nanotubes containing a benzene ring cycle with p orbitals aligned in a plane [ 14 ]. Such behavior allows them to be classified as armchair, zigzag, or chiral nanoribbons according to the chirality index [ 14 , 15 ]. In addition to the ring shape, carbon nanobelts are interesting structures due to their synthetic challenges and differentiated properties [ 16 , 17 ].…”

Structures and Supramolecular Properties of Inclusion Complexes of Anthracene‐Triptycene Nanocages with Fullerene Guests and Their Dynamic Motion as Molecular Gyroscopes

“…Most of the previous supramolecular systems with fullerene guests are mainly driven by face‐to‐face type π⋅⋅⋅π interactions between the curved π surface of fullerenes and aromatic units of the host molecules. Examples of such supramolecular hosts include ring‐, [8a,9] belt‐, [8e] cage‐, [8f] and bowl‐shaped hosts, [8g] many of which had large association constants due to wide contact area. On the other hand, the fullerene complexes stabilized by point‐to‐face interactions, such as S⋅⋅⋅π [10] and CH⋅⋅⋅π interactions, [6e,11,12] were limited.…”