Two polymorphic structures of the Schiff base 2-1-[(2-aminophenyl)imino]ethylphenol, compound (1), C14H14N2O are reported. Depending on the solvent used for recrystallization it crystallizes as either a monoclinic or an orthorhombic polymorph. The monoclinic form, polymorph [1] contains three, while the orthorhombic polymorph [2] contains only one molecule in the asymmetric unit. In both polymorphs, a strong intramolecular O-H•••N hydrogen bond is present from the stereochemical reason due to the rigidity of the chelate ring. Weak intermolecular N-H•••O interactions appearing in both structures combine the molecules in the form of infinite columns by the graph-set motif C22(7).
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