A 1:1 co-crystal of quinol and pyridine

Abstract

A co-crystal of quinol and pyridine would be expected to form with 1:2 stoichiometry because quinol has two hydrogen-bond donors and pyridine has one hydrogen-bond acceptor which is more basic than phenolic oxygen. We report the structure of a 1:1 co-crystal, viz. quinol-pyridine (1/1), C6H 6O2·C5H5N, which does not conform to this expectation. Its stability appears to imply that a combination of individually relatively weak C-H⋯O, C-H⋯π and π-π stacking interactions are energetically competitive with O-H⋯N hydrogen bonds. Quinol molecules lie on inversion centres, while pyridine is in a general position. © 2004 International Union of Crystallography Printed in Great Britain - all rights reserved.