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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
A new hexaaminomacrocycle for ditopic binding of bromide
Don Gibson1, Kalpana R Dey, Frank R Fronczek
1Department of Chemistry and Biochemistry, Jackson State University, Jackson, MS 39217, USA.
None:
A hexaaminomacrocycle L, containing four secondary and two tertiary amines has been synthesized and crystallized with hydrobromic acid. Structural analysis of the bromide complex suggests that the ligand in its tetrtaprotonated form, is involved in coordinating two bromides from both sides via hydrogen bonding interactions with N…Br(-) distance of 3,351 Å, forming a ditopic complex. The other two bromides are outside the cavity, and singly bonded to the macrocycle. The molecules are packed showing layer structures in which the internal bromides are locked between the layers of macrocycles. The bromide anions are coordinated alternatively by one and two hydrogen bonds with the protonated amines from the two adjacent macrocycles.
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