Dynamic Covalent Formation of Concave Disulfide Macrocycles Mechanically Interlocked with Single‐Walled Carbon Nanotubes. Issue 42 (25th August 2020)

• Record Type: Journal Article
• Authors: Balakrishna, Bugga; Menon, Arjun; Cao, Kecheng; Gsänger, Sebastian; Beil, Sebastian B.; Villalva, Julia; Shyshov, Oleksandr; Martin, Oliver; Hirsch, Andreas; Meyer, Bernd; Kaiser, Ute; Guldi, Dirk M.; von Delius, Max
• Is Part Of: Angewandte Chemie international edition. Volume 59:Issue 42(2020)
• Page Start: 18774
• Page End: 18785
• Publication Date: 2020-08-25
• Subjects: curved π-systems -- disulfide exchange -- mechanically interlocked architectures -- single-walled carbon nanotubes -- supramolecular chemistry; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.202005081
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: The formation of discrete macrocycles wrapped around single‐walled carbon nanotubes (SWCNTs) has recently emerged as an appealing strategy to functionalize these carbon nanomaterials and modify their properties. Here, we demonstrate that the reversible disulfide exchange reaction, which proceeds under mild conditions, can install relatively large amounts of mechanically interlocked disulfide macrocycles on the one‐dimensional nanotubes. Size‐selective functionalization of a mixture of SWCNTs of different diameters were observed, presumably arising from error correction and the presence of relatively rigid, curved π‐systems in the key building blocks. A combination of UV/Vis/NIR, Raman, photoluminescence excitation, and transient absorption spectroscopy indicated that the small (6, 4)‐SWCNTs were predominantly functionalized by the small macrocycles 12, whereas the larger (6, 5)‐SWCNTs were an ideal match for the larger macrocycles 22 . This size selectivity, which was rationalized computationally, could prove useful for the purification of nanotube mixtures, since the disulfide macrocycles can be removed quantitatively under mild reductive conditions. Abstract : Reversible clipping : The dynamic covalent opening and closing of disulfide macrocycles allowed the diameter‐selective functionalization of SWCNTs with mechanically interlocked rings.