Dr Erica Benedetti - Université Paris Cité

**Erica Benedetti** *Université Paris Cité, CNRS, Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, F-75006 Paris, France* **Abstract**  [2.2]Paracyclophanes (pCps) are fascinating three-dimensional molecular structures in which two aromatic rings are held face-to-face by two short carbon bridges. This unusual architecture gives rise to distinctive structural and electronic properties, making pCps attractive building blocks in modern organic chemistry.[1] In this lecture, we will first introduce the main structural features of [2.2]paracyclophanes and discuss how these molecules can be synthesized and selectively functionalized. Particular attention will be given to the concept of planar chirality, an original form of chirality that arises from the three-dimensional arrangement of substituted pCps, and to synthetic strategies that allow its control.[2] We will then explore how structural modifications of the pCp framework can influence its photophysical properties, including absorption and fluorescence, and how these properties can be exploited to design new luminescent molecules.[3] Finally, we will illustrate how [2.2]paracyclophanes can serve as three-dimensional molecular platforms for applications at the interface between chemistry and biology, with a particular focus on the development of molecules capable of interacting with nucleic acids.[4] Through these examples, the lecture will highlight how molecular structure, synthetic chemistry and photophysical properties can be combined to design functional molecules and address questions ranging from materials chemistry to chemical biology.  **References** [1] C. J. Brown and A. C. Farthing, *Nature*, **164** (1949) 915. [2] a) M.-L. Delcourt, S. Turcaud, E. Benedetti, L. Micouin, *Adv. Synth. Catal.* **358** (2016) 1213; b) M.-L. Delcourt, S. Felder, E. Benedetti, L. Micouin, *ACS Catal.* **8** (2018) 6612. [3] a) S. Felder, M.-L. Delcourt, R. Rodríguez, L. Favereau, J. Crassous, L. Micouin, E. Benedetti, *J. Mater. Chem. C* **11** (2023) 2053; b) S. Wu, L.A. Galan, M. Roux, F. Riobe, B. Le Guennic, Y. Guyot, T. Le Bahers, L. Micouin, O. Maury, E. Benedetti, *Inorg. Chem.* **60** (2021) 16194. [4] a) S. Felder, C. Sagné, E. Benedetti, L. Micouin, *ACS Chem. Biol.* **17** (2022) 3069; b) R. Sun, C. Siretanu, G. Ilieska, S. Felder, E. Benedetti, L. Micouin, *ChemBioChem* **27** (2026) e202500835.