Crystal structures of aroylhydrazones derived from 5-methoxysalicylaldehyde

Two new aroylhydrazones 3-bromo-N′-(2-hydroxy-5-methoxybenzylidene)benzohydrazide (1) and 4-hydroxy-3-methoxy-N′-(2-hydroxy-5-methoxybenzylidene)benzohydrazide (2), derived from 5-methoxysalicylaldehyde, are prepared and determined by means of infrared and ¹H NMR spectroscopy and single crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic space group P2₁/n with a = 5.9406(7) Å, b = 31.833(3) Å, c = 7.6460(8) Å, β = 94.522(4)°, V = 1441.4(3) ų, Z = 4. Compound 2 crystallizes in the monoclinic space group P2₁/c with a = 14.3471(9) Å, b = 11.3893(7) Å, c = 9.6853(6) Å, β = 94.063(2)°, V = 1578.6(2) ų, Z = 4. Both molecules have very similar bond lengths and angles. The crystal structures of both compounds are stabilized by N-H...O and O-H...O hydrogen bonds as well as π...π interactions.