Crystal structures of three functionalized chalcones: 4⁰-dimethylamino-3-nitrochalcone, 3-dimethylamino-3⁰-nitrochalcone and 3⁰-nitro-chalcone

The structure of three functionalized chalcones (1,3-diarylprop-2-en-1-ones), containing combinations of nitro and dimethylamino functional groups, are presented, namely, 1-[4-(dimethylamino)phenyl]-3-(3-nitrophenyl)prop-2-en-1-one, C₁₇H₁₆N₂O₃, Gp8m, 3-[3-(dimethylamino)phenyl]-1-(3-nitrophenyl)prop-2-en-1-one, C₁₇H₁₆N₂O₃, Hm7m and 1-(3-nitrophenyl)-3-phenylprop-2-en-1-one, C₁₅H₁₁NO₃, Hm1-. Each of the molecules contains bonding motifs seen in previously solved crystal structures of functionalized chalcones, adding to the large dataset available for these small organic molecules. The structures of all three of the title compounds contain similar bonding motifs, resulting in two-dimensional planes of molecules formed via C-H…O hydrogen-bonding interactions involving the nitro- and ketone groups. The structure of Hm1- is very similar to the crystal structure of a previously solved isomer [Jing (2009). Acta Cryst. E65, o2510].