Conformational plasticity of hydrogen bonded bis-urea supramolecular polymers

P. Brocorens (1) , M. Linares (2) , Carine Guyard-Duhayon (3) , R. Guillot (4) , B. Andrioletti (5) , D. Suhr (6) , B. Isare (6) , R. Lazzaroni (1) , Laurent Bouteiller (6)

1 UMons - Université de Mons
2 Department of Science and Technology [Linköping]
3 LCC - Laboratoire de chimie de coordination
4 ICMMO - Institut de Chimie Moléculaire et des Matériaux d'Orsay
5 ICBMS - Institut de Chimie et Biochimie Moléculaires et Supramoléculaires
6 LCP - Chimie des polymères

We report a detailed structural investigation of supramolecular polymers formed by hydrogen bonded self-assembly of bis-urea monomers. The careful exploration of the energy landscape by molecular mechanics/molecular dynamics (MM/MD) simulations has allowed us to identify three distinct self-assembled structures of similar stabilities. These structures have been compared to X-ray crystal data. We observe that a slight change in the molecular structure can favor a particular structure over the others. Detailed analysis shows that hydrogen bonds stabilize all three structures to a similar extent. Therefore, it is the interactions among the lateral substituents, and with the filament environment, that are the decisive factors in the competition between the possible self-assembled structures. This study constitutes a clear reminder that the conformation of a supramolecular polymer is a sensitive function of the molecular structure and may significantly differ from the solid-state conformation of a model compound.

Domaines: Chimie théorique et/ou physique

P. Brocorens, M. Linares, Carine Guyard-Duhayon, R. Guillot, B. Andrioletti, et al.. Conformational plasticity of hydrogen bonded bis-urea supramolecular polymers. Journal of Physical Chemistry B, 2013, 117 (17), pp.5379-5386. ⟨10.1021/jp401915y⟩. ⟨hal-00993522⟩