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Updated: Jan 24, 2026

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Synthesis and Evaluation of Azolium-Based Halogen-Bond Donors
Richard A Squitieri1, Keegan P Fitzpatrick1, Ashley A Jaworski1
1Department of Chemistry, Center for Molecular Innovation and Drug Discovery, Northwestern University, Silverman Hall, Evanston, Illinois, 60208, USA.
Abstract:
A method for the synthesis of iodinated imidazolium and triazolium N-heterocyclic halogen-bond-donor catalysts has been developed. This approach was applied to the synthesis of a variety of 1,2,4-triazolium salts to prepare a series of novel chiral halogen-bond-donor catalysts. The counterions of the iodinated triazoliums can be readily exchanged with chiral and achiral non-coordinating counterions to produce unique scaffolds. Their ability to promote/catalyse a conjugate addition reaction with indole was investigated. Through these initial studies, a set of general guidelines and considerations for the application of these halogen-bond donors in organocatalysis have been established.
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