Bambusuril Small-Molecule Ionic Isolation Lattices for Exciton Coupled Dimers and Dicationic Fluorophores

Ionic self-assembly of molecular fluorophores is a promising avenue to program properties into optical materials. Controllable optical energies, lifetimes, exciton hopping and energy transfer have bee...

pubs.acs.org

Multi-Ion Complexes and Competition from Bulky BArF– Anions for Chloride Binding in Ion Pairing Conditions

Cationic charges have long been used to enhance anion binding. Embedding charge introduces strong ion pairing for target anions but also for off-target ions, ultimately generating a mixture of multi-ion species that are hard to identify and quantify. While many sidestep this problem using polar solvents and weakly coordinating ions, these approaches exclude a substantial cross-section of conditions found in applications spanning recognition, assembly, separations, templation, and catalysis. To confront this complexity, we study the binding of an anion to a cationic receptor featuring low shape complementarity in a low-polarity solvent to maximize ionic interactions. We prepared the receptor as a salt of the weakly coordinating tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (BArF–) anion and studied the binding of small chloride (Cl–) and medium-sized iodide (I–) anions. Surprisingly, the use of the bulky BArF– anion does not suppress ion pairing interactions, with 65% of the receptor being paired at 0.5 mM in dichloromethane. We observe multi-ion receptor-Cl– complexes (2:1, 1:1, 1:2), reinforcing the complexity that emerges when working in low-polarity media. We reveal the dependence of affinity on anion charge density and size and that bulky BArF– counteranions compete for chloride binding. These studies reveal the noninnocence of BArF– anions and strategies to quantify multi-ion species.

pubs.acs.org

Cyanostar synthesis on large or rapid scales†

Cyanostar is a pentagonal macrocycle that is selective for polyatomic anions. Use of cyanostar in research and technology has grown since its debut in 2013 with more than 40 publications and 5 pate...

tandfonline.com

Take two polls to help Iupac define molecular machines

An Iupac committee wants your input to guide its recommendations for key terms in the field

chemistryworld.com

Selective Binding and Light-Driven Release of Fluorous PF6– and Radioactive 99TcO4– Anions for All-to-Nothing Liquid–Liquid Extraction

The removal of anions from aqueous media using molecular receptors in liquid–liquid extraction is a long-standing strategy to clean up contaminated water sources. Therein, high selectivity is needed t...

pubs.acs.org

Supramolecular Control of Helicene Circularly Polarized Luminescence Emitters in Molecular Solids and Bright Nanoparticles

The intrinsic molecular chiroptical properties (electronic circular dichroism and circular polarized luminescence) of helicences are perfectly transferred from solution to the crystal state and to wa....

onlinelibrary.wiley.com