{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"omics_type":["Unknown"],"volume":["14(1)"],"submitter":["Mirabella CFM"],"pubmed_abstract":["We report the self-assembly of shape-persistent [1 + 1] tetra-imine cages 1 based on two different tetra-α aryl-extended calix[4]pyrrole scaffolds in chlorinated solvents and in a 9 : 1 CDCl<sub>3</sub> : CD<sub>3</sub>CN solvent mixture. We show that the use of a bis-<i>N</i>-oxide 4 (4,4'-dipyridyl-<i>N,N</i>'-dioxide) as template is not mandatory to induce the emergence of the cages but has a positive effect on the reaction yield. We use <sup>1</sup>H NMR spectroscopy to investigate and characterize the binding properties (kinetic and thermodynamic) of the self-assembled tetra-imine cages 1 with pyridine <i>N</i>-oxide derivatives. The cages form kinetically and thermodynamically stable inclusion complexes with the <i>N</i>-oxides. For the bis-<i>N</i>-oxide 4, we observe the exclusive formation of 1 : 1 complexes independently of the solvent used. In contrast, the pyridine-<i>N</i>-oxide 5 (mono-topic guest) produces inclusion complexes displaying solvent dependent stoichiometry. The bis-<i>N</i>-oxide 4 is too short to bridge the gap between the two endohedral polar binding sites of 1 by establishing eight ideal hydrogen bonding interactions. Nevertheless, the bimolecular 4⊂1 complex results as energetically favored compared to the 5<sub>2</sub>⊂1 ternary counterpart. The inclusion of the <i>N</i>-oxides, 4 and 5, in the tetra-imine cages 1 is significantly faster in chlorinated solvents (minutes) than in the 9 : 1 CDCl<sub>3</sub> : CD<sub>3</sub>CN solvent mixture (hours). We provide an explanation for the similar energy barriers calculated for the formation of the 4⊂1 complex using the two different ternary counterparts 5<sub>2</sub>⊂1 and (CD<sub>3</sub>CN)<sub>2</sub>⊂1 as precursors. We propose a mechanism for the in-out guest exchange processes experienced by the tetra-imine cages 1."],"journal":["Chemical science"],"pagination":["186-195"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC9769375"],"repository":["biostudies-literature"],"pubmed_title":["Influence of the solvent in the self-assembly and binding properties of [1 + 1] tetra-imine bis-calix[4]pyrrole cages."],"pmcid":["PMC9769375"],"pubmed_authors":["Mirabella CFM","Aragay G","Ballester P"],"additional_accession":[]},"is_claimable":false,"name":"Influence of the solvent in the self-assembly and binding properties of [1 + 1] tetra-imine bis-calix[4]pyrrole cages.","description":"We report the self-assembly of shape-persistent [1 + 1] tetra-imine cages 1 based on two different tetra-α aryl-extended calix[4]pyrrole scaffolds in chlorinated solvents and in a 9 : 1 CDCl<sub>3</sub> : CD<sub>3</sub>CN solvent mixture. We show that the use of a bis-<i>N</i>-oxide 4 (4,4'-dipyridyl-<i>N,N</i>'-dioxide) as template is not mandatory to induce the emergence of the cages but has a positive effect on the reaction yield. We use <sup>1</sup>H NMR spectroscopy to investigate and characterize the binding properties (kinetic and thermodynamic) of the self-assembled tetra-imine cages 1 with pyridine <i>N</i>-oxide derivatives. The cages form kinetically and thermodynamically stable inclusion complexes with the <i>N</i>-oxides. For the bis-<i>N</i>-oxide 4, we observe the exclusive formation of 1 : 1 complexes independently of the solvent used. In contrast, the pyridine-<i>N</i>-oxide 5 (mono-topic guest) produces inclusion complexes displaying solvent dependent stoichiometry. The bis-<i>N</i>-oxide 4 is too short to bridge the gap between the two endohedral polar binding sites of 1 by establishing eight ideal hydrogen bonding interactions. Nevertheless, the bimolecular 4⊂1 complex results as energetically favored compared to the 5<sub>2</sub>⊂1 ternary counterpart. The inclusion of the <i>N</i>-oxides, 4 and 5, in the tetra-imine cages 1 is significantly faster in chlorinated solvents (minutes) than in the 9 : 1 CDCl<sub>3</sub> : CD<sub>3</sub>CN solvent mixture (hours). We provide an explanation for the similar energy barriers calculated for the formation of the 4⊂1 complex using the two different ternary counterparts 5<sub>2</sub>⊂1 and (CD<sub>3</sub>CN)<sub>2</sub>⊂1 as precursors. We propose a mechanism for the in-out guest exchange processes experienced by the tetra-imine cages 1.","dates":{"release":"2022-01-01T00:00:00Z","publication":"2022 Dec","modification":"2025-04-04T13:13:17.548Z","creation":"2025-04-04T13:13:17.548Z"},"accession":"S-EPMC9769375","cross_references":{"pubmed":["36605742"],"doi":["10.1039/d2sc05311j"]}}