3‐Methoxy‐5‐(4‐methyl­phenyl­diazenyl)­salicyl­aldehyde and 3‐methoxy‐5‐(2‐methyl­phenyl­diazenyl)­salicyl­aldehyde

The two title mol­ecules, both C₁₅H₁₄N₂O₃, are roughly planar and display a trans conformation with respect to the –N=N– double bond, as found for other diazene derivatives. In both compounds, there are intramolecular O—H⋯O hydrogen bonds and the crystal packing is governed by weak intermolecular C—H⋯O hydrogen bonds and π–π stacking.