Acridinium pi-dimer for Motion of Large Amplitude on Surfaces

We recently reported bis-acridinium receptors able to bind guest molecules.[1] In these receptors, two acridinium recognition units linked by a semi-rigid spacer are pre-organized to bind a variety of aromatic guests. The acridinium recognition units are unique multi-responsive building blocks (electrochemically and chemically switchable) able to interact with electron rich guests.[2] Surprisingly, this class of bis-acridinium receptors exhibit i) self-complementary behaviors leading to the formation of entwined dimers,[1a] ii) narcissistic self-sorting as well[1b] as iii) pi-donor/pi-acceptor host-guest behaviors.[3] Upon monoelectronic reduction using cobaltocene, the formation of acridinium pi-dimers was observed in some receptors. The corresponding cyclophane was recently incorporated in a [2]rotaxane structure.[4]

This project aims at developing an innovative class of poly-acridinium rotaxanes in order to complete the demonstration of pi-dimer formation between reduced acridinium cores. The development of novel building blocks in this field is challenging on account of the weak stability of pi-dimers at room temperature. [2]rotaxane architectures will be developed to offer a thermodynamic and kinetic stabilization to study and allow the determination of acridinium pi-dimerization upon reduction. Then, novel bis-acridinium macrocycles will be developed to graft poly-acridinium rotaxanes on gold electrode surfaces in order to use electrons as fuel to trigger a motion of large amplitude.

[1] a) H.-P. Jacquot de Rouville, N. Zorn, E. Leize-Wagner, V. Heitz Chem. Commun. 2018, 54, 10966–10969 ; b) H.-P. Jacquot de Rouville, C. Gourlaouen, and V. Heitz, Dalton Trans., 2019, 48, 8725–8730 ; [2] H.-P. Jacquot de Rouville, J. Hu, V. Heitz, ChemPlusChem, 2021, 86, 110–129 ; [3] J. Hu, J. S. Ward, A. Chaumont, K. Rissanen, J.-M. Vincent, V. Heitz, H.-P. Jacquot de Rouville, Angew. Chem. Int. Ed., 2020, 59, 23206–23212 ; [4] J. Hu, S. Adrouche, E. S. Gauthier, N. Le Breton, M. Cecchini, C. Gourlaouen, S. Choua, V. Heitz, H.-P. Jacquot de Rouville Chem. Eur. J., 2022, 28, e202202840.

Funding category: Financement public/privé
Fondation Jean-Marie Lehn
PHD title: Doctorat de Chimie
PHD Country: France