The title compound, C8H7NO5, is planar with an r.m.s. deviation for all non-hydrogen atoms of 0.018 Å. An intramolecular O—H...O hydrogen bond involving the adjacent hydroxy and nitro groups forms an S(6) ring motif. In the crystal, molecules are linked by O—H...O hydrogen bonds, forming chains propagating along the b-axis direction. The chains are linked by C—H...O hydrogen bonds, forming layers parallel to the bc plane. The layers are linked by a further C—H...O hydrogen bond, forming slabs, which are linked by C=O...π interactions, forming a three-dimensional supramolecular structure. Hirshfeld surface analysis was used to investigate intermolecular interactions in the solid state. The molecule was also characterized spectroscopically and its thermal stability investigated by differential scanning calorimetry and by thermogravimetric analysis.

The title compound, [Co(C15H11O2)2(C4H4NO)2], was obtained from bis(1‐phenylpropane‐1,3‐dionato)cobalt(II) after crystallization from morpholine. The Co atom is located on a crystallographic inversion centre with an octahedral environment formed by four O atoms of the two 1,3‐diphenylpropane‐1,3‐dione ligands and two N atoms from two morpholine molecules. Both morpholine molecules are additionally involved in N—H...π interactions with the chelate ring (N...centroid = 2.70 Å).