A Long-Lived Halogen-Bonding Anion Triple Helicate Accommodates Rapid Guest Exchange

Casey J. Massena, Daniel A. Decato, Orion B. Berryman

Research output: Contribution to journalArticlepeer-review

Abstract

Anion-templated helical structures are emerging as a dynamic and tractable class of supramolecules that exhibit anion-switchable self-assembly. We present the first kinetic studies of an anion helicate by utilizing halogen-bonding m-arylene-ethynylene oligomers. These ligands formed high-fidelity triple helicates in solution with surprisingly long lifetimes on the order of seconds even at elevated temperatures. We propose an associative ligand-exchange mechanism that proceeded slowly on the same timescale. In contrast, intrachannel anion exchange occurred rapidly within milliseconds or faster as determined by stopped-flow visible spectroscopy. Additionally, the helicate accommodated bromide in solution and the solid state, while the thermodynamic stability of the triplex favored larger halide ions (bromide≈iodide≫chloride). Taken together, we elucidate a new class of kinetically stable helicates. These anion-switchable triplexes maintain their architectures while accommodating fast intrachannel guest exchange.

Original languageEnglish
Pages (from-to)16109-16113
Number of pages5
JournalAngewandte Chemie - International Edition
Volume57
Issue number49
DOIs
StatePublished - Dec 3 2018

Keywords

  • halogen bonding
  • helical structures
  • host-guest systems
  • kinetics
  • supramolecular chemistry

Fingerprint

Dive into the research topics of 'A Long-Lived Halogen-Bonding Anion Triple Helicate Accommodates Rapid Guest Exchange'. Together they form a unique fingerprint.

Cite this