Oxime–Carboxyl Hydrogen Bonds: the Preferred Interaction Determining Crystal Packing of `Carboxyoximes'

Abstract

The statistical analysis of hydrogen-bond interactions formed by oximes and carboxylic acids has been performed. Ab initio quantum-chemical calculations have been used to rationalize the observed preference for the oxime–carboxyl interaction compared with homologous binding (carboxyl–carboxyl and oxime–oxime). The crystal packing observed in the structure of pyruvic acid oxime (hydroxyiminopyruvic acid) has been explained as the consequence of a combination of the energetically optimal structure of the isolated molecule and the optimal interaction of monomers forming a dimer.