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Updated: Nov 7, 2025
06:44
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
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Unraveling Halogen Effects in Supramolecular Polymerization
Jonas Matern1, Nils Bäumer1, Gustavo Fernández1
1Organisch-Chemisches Institut, Universität Münster, Corrensstraße 36, 48149 Münster, Germany.
Journal of the American Chemical Society
|April 29, 2021
Summary
The halogen
Area of Science:
- Supramolecular chemistry
- Coordination chemistry
- Materials science
Background:
- Halogen effects in supramolecular polymerization are poorly understood.
- Previous studies focused on halogen bonding or polyfluorinated groups.
- Chlorine ligands were shown to influence molecular packing in metal complexes.
Purpose of the Study:
- To investigate the role of halogen nature in supramolecular polymerization.
- To explore halogen effects beyond traditional halogen bonding.
- To understand how different halogens influence self-assembly pathways.
Main Methods:
- Design and synthesis of archetypal bispyridyldihalogen Pt(II) complexes (Cl, Br, I).
- Systematic comparison of supramolecular polymerization in nonpolar media.
- Utilized various experimental techniques and theoretical calculations.
Main Results:
- Observed remarkably different supramolecular polymerization behaviors for Cl, Br, and I complexes.
- Identified two competing pathways: slipped (kinetic) and parallel (thermodynamic) molecular packing.
- Halogens inversely affected the energetic levels of self-assembled states, influencing pathway dominance.
Conclusions:
- Halogen nature dictates supramolecular polymerization pathways and molecular packing.
- Weak N-H···X hydrogen bonds in the kinetic pathway involve halogens.
- Solvophobic effects are amplified by halogens in the thermodynamic pathway.
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