Halogen-substituted ureas for anion binding: solid state and solution studies

Casula, Arianna; Fornasier, Marco; Montis, Riccardo; Bettoschi, Alexandre; Argent, Stephen P.; Blake, Alexander J.; Lippolis, Vito; Marongiu, Laura; Picci, Giacomo; Tidey, Jeremiah P.; Caltagirone, Claudia

Abstract

Herein, we report the synthesis and the anion binding properties of a family of N,N′-diphenylureas L1-L15, bearing on the aromatic ring(s) halogens (chlorine and iodine) and/or nitro or trifluoromethyl electron-withdrawing groups. The analysis of the crystal structures obtained from single crystal X-ray diffraction experiments shows that self-assembled chains or tapes connected via N–H···O hydrogen bonds are the most commonly adopted arrangements for this type of molecules in the crystal lattice. In the presence of anion guests or solvent molecules with competing hydrogen bond donors and acceptors, other supramolecular arrangements can be observed. Solution studies conducted in DMSOd 6/0.5% H2O by means of 1H-NMR titrations show the formation of 1:1 adducts with all receptors. The different observed affinities of the receptors for the anion guests were rationalised in terms of steric hindrance of the substituents on the phenyl rings and their electron-withdrawing properties.

Citation

Casula, A., Fornasier, M., Montis, R., Bettoschi, A., Argent, S. P., Blake, A. J., …Caltagirone, C. (in press). Halogen-substituted ureas for anion binding: solid state and solution studies. Supramolecular Chemistry, https://doi.org/10.1080/10610278.2017.1377343

• Journal Article Type: Article
• Acceptance Date: Sep 2, 2017
• Online Publication Date: Sep 24, 2017
• Deposit Date: Oct 5, 2017
• Publicly Available Date: Sep 25, 2018
• Journal: Supramolecular Chemistry
• Print ISSN: 1061-0278
• Electronic ISSN: 1029-0478
• Publisher: Taylor & Francis Open
• Peer Reviewed: Peer Reviewed
• DOI: https://doi.org/10.1080/10610278.2017.1377343
• Keywords: anion binding, phenylurea
• Public URL: https://nottingham-repository.worktribe.com/output/884536
• Publisher URL: http://www.tandfonline.com/doi/full/10.1080/10610278.2017.1377343
• Additional Information: This is an Accepted Manuscript of an article published by Taylor & Francis in Supramolecular Chemistry on 24.09.2017, available online: http://www.tandfonline.com/http://dx.doi.org/10.1080/10610278.2017.1377343