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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Noncovalent Lone Pair⋅⋅⋅(No-π!)-Heteroarene Interactions: The Janus-Faced Hydroxy Group
Ilias Pavlakos1, Tanzeel Arif1, Abil E Aliev2
1Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (UK).
Abstract:
A comparative study using NMR spectroscopy and designed top-pan molecular balances demonstrates that the noncovalent interaction of a hydroxy group with π-deficient pyrazine and quinoxaline units involves a lone pair-heteroarene interaction which is much stronger and solvent independent when measured relative to the classical π-facial hydrogen bond to a benzene ring. Alkyl fluorides also prefer the heteroarene rings over the benzene ring. The attractive interaction between a quinoxaline and a terminal alkyne is also stronger than the intramolecular hydrogen bond to an arene.
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