Crystal structures of two 4H-chromene derivatives: 2-amino-3-cyano-4-(3,4-dichlorophenyl)-7-hydroxy-4H-benzo[1,2-b]pyran 1,4-dioxane monosolvate and 2-amino-3-cyano-4-(2,6-dichlorophenyl)-7-hydroxy-4H-benzo[1,2-b]pyran

In the title compounds, C16H9Cl2N2O2·C4H8O2 and C16H9Cl2N2O2, the bicyclic 4H-chromene cores are nearly planar with maximum deviations of 0.081 (2) and 0.087 (2) Å. In both structures, the chromene derivative molecules are linked into centrosymmetric dimers by pairs of N—H...O hydrogen bonds, forming R22(16) motifs. These dimers are further linked in the 3,4-dichlorophenyl derivative by N—H...N hydrogen bonds into double layers parallel to (100) and in the 2,6-dichlorophenyl derivative by O—H...N hydrogen bonds into ribbons along the [1\overline{1}0] direction. In the 3,4-dichlorophenyl derivative, the 1,4-dioxane solvent molecules are connected to the chromene molecules via O—H...O hydrogen bonds.