Introduction
Nanographenes (NGs) have usually been synthetized following a top-down approach by “cutting” a graphene sheet into smaller fragments using chemical or physical methods. Although this methodology starts from readily accessible bulk materials and it is easily scalable, it does not allow a fine control of the properties due to the polydispersion in sizes and shapes of the final material. In contrast, the bottom-up approach in which NGs are grown up from smaller chemical entities using solution-phase benchtop organic synthesis, leads to monodisperse molecules with a precise control on the size and shape, exhibiting fine-tuned optoelectronic properties.
Thus, taking advantage of the versatility that provides the set of organic reactions available, and the selectivity of these transformations depending on the reaction conditions, a large number of molecular NGs have been synthetized by design in the recent years. An example of this control is the introduction of out-of-plane defects at will, namely curvature, helicity, or strain, resulting in the presence of chirality as an additional and remarkable structural control.
Along the last recent years, we have carried out the synthesis and unveiled the properties of a variety of molecular nanographenes in the search for new chiroptical and optoelectronic properties in all-carbon materials.[1-5] In this presentation some recent and amazing NGs stemming from our research group, with special emphasis on the search for enantioselectivity, will be presented and discussed.
References
[1] J. M. Fernández-García, P. J. Evans, S. Filippone, M. A. Herranz, N. Martín, “Chiral Molecular Carbon Nanostructures”, Acc. Chem. Res. 2019, 52, 1565-1574.
[2] P. J. Evans, et al., Angew. Chem. Int. Ed. 2018, 57, 6774 –6779.
[3] Z. Zhou, J. M. Fernández-García, et al. Angew. Chem. Int. Ed. 2022, 61, e20211574.
[4] Patricia Izquierdo-García, et al. J. Am. Chem. Soc. 2023, 145, 11599-11610.
[5] M. Buendía-Mateos, et al. Nat. Synth. 2024, accepted for publication.