Crystal structures of the two isomeric hydrogen-bonded cocrystals 2-chloro-4-nitro-benzoic acid-5-nitro-quinoline (1/1) and 5-chloro-2-nitro-benzoic acid-5-nitro-quinoline (1/1).

The structures of two isomeric com-pounds of 5-nitro-quinoline with chloro- and nitro-substituted benzoic acid, namely, 2-chloro-4-nitro-benzoic acid-5-nitro-quinoline (1/1), (I), and 5-chloro-2-nitro-benzoic acid-5-nitro-quinoline (1/1), (II), both CHClNO·CHNO, have been determined at 190 K. In each com-pound, the acid and base mol-ecules are held together by an O-H⋯N hydrogen bond. In the crystal of (I), the hydrogen-bonded acid-base units are linked by a C-H⋯O hydrogen bond, forming a tape structure along [10]. The tapes are stacked into a layer parallel to the plane N-O⋯π inter-actions between the nitro group of the base mol-ecule and the quinoline ring system. The layers are further linked by other C-H⋯O hydrogen bonds, forming a three-dimensional network. In the crystal of (II), the hydrogen-bonded acid-base units are linked into a wide ribbon structure running along [10] C-H⋯O hydrogen bonds. The ribbons are further linked another C-H⋯O hydrogen bond, forming a layer parallel to (110). Weak π-π inter-actions [centroid-centroid distances of 3.7080 (10) and 3.7543 (9) Å] are observed between the quinoline ring systems of adjacent layers. Hirshfeld surfaces for the 5-nitro-quinoline mol-ecules of the two com-pounds mapped over shape index and were generated to visualize the weak inter-molecular inter-actions.