Transoid-to-Cisoid Conformation Changes of Single Molecules on Surfaces Triggered by Metal Coordination

Sara Freund; Rémy Pawlak; Lucas Moser; Antoine Hinaut; Roland Steiner; Nathalie Marinakis; Edwin C. Constable; Ernst Meyer; Catherine E. Housecroft; Thilo Glatzel

doi:10.1021/acsomega.8b01792

arXiv · 1807.04011

Transoid-to-Cisoid Conformation Changes of Single Molecules on Surfaces Triggered by Metal Coordination

Sara Freund·Rémy Pawlak·Lucas Moser·Antoine Hinaut·Roland Steiner·Nathalie Marinakis·Edwin C. Constable·Ernst Meyer·Catherine E. Housecroft·Thilo Glatzel

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Abstract

Conformational isomers are stereoisomers that can interconvert over low potential barriers by rotation around a single bond. However, such bond rotation is hampered by geometrical constraints when molecules are adsorbed on surfaces. Here we show that the adsorption of 4,4'-bis(4-carboxyphenyl)-6,6'-dimethyl-2,2'-bipyridine molecules on surfaces leads to the appearance of pro-chiral single-molecules on NiO(001) and to enantiopure supramolecular domains on Au(111) surfaces containing the $transoid$ molecule conformation. Upon additional Fe adatom deposition, molecules undergo a controlled interconversion from a $transoid$ to $cisoid$ conformation as a result of coordination of the Fe atoms to the 2,2'-bipyridine moieties. As confirmed by atomic force microscopy images and X-ray photoelectron spectroscopy measurements, the resulting molecular structures become irreversibly achiral.

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Sara Freund, Rémy Pawlak, Lucas Moser, Antoine Hinaut, Roland Steiner, Nathalie Marinakis, Edwin C. Constable, Ernst Meyer, Catherine E. Housecroft, Thilo Glatzel. 2018-10-15. Transoid-to-Cisoid Conformation Changes of Single Molecules on Surfaces Triggered by Metal Coordination. https://doi.org/10.1021/acsomega.8b01792

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