Halogen-substituted ureas for anion binding: solid state and solution studies. Issue 11 (2nd November 2017)

• Record Type: Journal Article
• Authors: 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
• Is Part Of: Supramolecular chemistry. Volume 29:Issue 11(2017)
• Page Start: 875
• Page End: 886
• Publication Date: 2017-11-02
• Subjects: Anion binding -- phenylurea; Macromolecules -- Periodicals; Supramolecular chemistry -- Periodicals; 547.005
• DOI: 10.1080/10610278.2017.1377343
• Languages: English
• ISSNs: 1061-0278

Abstract

Abstract: Herein, we report the synthesis and the anion binding properties of a family of N, N ′-diphenylureasL 1 -L 15, 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 DMSO- d 6 /0.5% H2 O by means of 1 H-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. Abstract :