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Updated: Feb 16, 2026
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Thioimidazolium Ionic Liquids as Tunable Alkylating Agents
Ryan Guterman1, Han Miao1, Markus Antonietti1
1Department of Colloid Chemistry, Max Planck Institute of Colloids and Interfaces Max Planck Institute for Colloids and Interfaces , Am Mühlenberg 1 OT-Golm, 14476 Potsdam, Germany.
Abstract:
Alkylating ionic liquids based on the thioimidazolium structure combine the conventional properties of ionic liquids, including low melting point and nonvolatility, with the alkylating function. Alkyl transfer occurs exclusively from the S-alkyl position, thus allowing for easy derivatization of the structure without compromising specificity. We apply this feature to tune the electrophilicty of the cation to profoundly affect the reactivity of these alkylating ionic liquids, with a caffeine-derived compound possessing the highest reactivity. Anion choice was found to affect reaction rates, with iodide anions assisting in the alkylation reaction through a "shuttling" process. The ability to tune the properties of the alkylating agent using the toolbox of ionic liquid chemistry highlights the modular nature of these compounds as a platform for alkylating agent design and integration in to future systems.
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