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Updated: Apr 3, 2026
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Crystal structure of di-chlorido-(4,11-dimethyl-1,4,8,11-tetra-aza-bicyclo-[6.6.2]hexa-deca-ne)iron(III)
Neil L Funwie1, Amy N Cain1, Brian Z Fanning1
1Department of Chemistry and Physics, Southwestern Oklahoma State University, Weatherford, OK 73096, USA.
Abstract:
The title compound, [FeCl2(C14H30N4)]PF6, contains Fe(3+) coordinated by the four nitro-gen atoms of an ethyl-ene cross-bridged cyclam macrocycle and two cis chloride ligands in a distorted octa-hedral environment. In contrast to other similar compounds this is a monomer. Inter-molecular C-H⋯Cl inter-actions exist in the structure between the complex ions. Comparison with the mononuclear Fe(2+) complex of the same ligand shows that the smaller Fe(3+) ion is more fully engulfed by the cavity of the bicyclic ligand. Comparison with the μ-oxido dinuclear complex of an unsubstituted ligand of the same size demonstrates that the methyl groups of 4,11-dimethyl-1,4,8,11-tetra-aza-bicyclo-[6.6.2]hexa-decane prevent dimerization upon oxidation.
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