Reciprocal hydrogen bonding-aromaticity relationships.

J Am Chem Soc

Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia 30602, United States.

Published: October 2014

Computed association energies and dissected nucleus-independent chemical shifts (NICS) document the mutual enhancement (or reduction) of intermolecular interactions and the aromaticity of H-bonded substrates. H-bonding interactions that increase cyclic 4n + 2 π-electron delocalization boost aromaticity. Conversely, such interactions are weakened when aromaticity is decreased as a result of more localized quinoidal π character. Representative examples of the tautomeric equilibria of π-conjugated heterocyclic compounds in protic solvents and other H-bonding environments also illustrate such H-bonding/aromaticity interplay.

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http://dx.doi.org/10.1021/ja507202fDOI Listing

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