Isobe Hiroyuki, Kotani Yuki, Matsuno Taisuke, Fukunaga Toshiya M, Ikemoto Koki
Department of Chemistry, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-0033, Japan.
Commun Chem. 2022 Nov 19;5(1):152. doi: 10.1038/s42004-022-00777-2.
Incommensurate double-wall carbon nanotubes give rise to unique stereochemistry originating from twisted stacks of hexagon arrays. However, atomic-level studies on such unique systems have rarely been performed, even though syntheses of molecular segments of carbon nanotubes have been extensively explored. The design of cylindrical molecules with chirality, particularly, in pairs provides synthetic challenges, because relationships between diameters specified with chiral indices and structures of arylene panels have not been investigated in a systematic manner. Here we show that a molecular version of incommensurate double-wall carbon nanotubes can be designed through the development of an atlas for the top-down design of cylindrical molecules. A large-bore cylindrical molecule with a diameter of 1.77 nm was synthesized using a readily available pigment and encapsulated a small-bore cylindrical molecule with a diameter of 1.04 nm. The large- and small-bore molecules possessed helicity in atomic arrangements, and their coaxial assembly proceeded in nonstereoselective manner to give both heterohelical and homohelical combinations.
非 commensurate 双壁碳纳米管产生了源自六边形阵列扭曲堆叠的独特立体化学。然而，尽管对碳纳米管分子片段的合成进行了广泛探索，但对这种独特体系的原子级研究却很少进行。特别是，设计具有手性的圆柱形分子对面临合成挑战，因为尚未系统研究用手性指数指定的直径与亚芳基面板结构之间的关系。在这里，我们表明，可以通过开发用于圆柱形分子自上而下设计的图谱来设计非 commensurate 双壁碳纳米管的分子版本。使用一种容易获得的颜料合成了直径为 1.77 纳米的大口径圆柱形分子，并封装了直径为 1.04 纳米的小口径圆柱形分子。大口径和小口径分子在原子排列上具有螺旋性，它们的同轴组装以非立体选择性方式进行，产生了异螺旋和同螺旋组合。
