Crystal structure of 4-chloro-2-nitro-benzoic acid with 4-hy-droxy-quinoline: a disordered structure over two states of 4-chloro-2-nitro-benzoic acid-quinolin-4(1H)-one (1/1) and 4-hy-droxy-quinolinium 4-chloro-2-nitro-benzoate.

Kazuma Gotoh,Hiroyuki Ishida

doi:10.1107/s205698901901497x

Kazuma Gotoh, Hiroyuki Ishida

Open Access

https://doi.org/10.1107/s205698901901497x

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Abstract

The title compound, C9H7.5NO·C7H3.5ClNO4, was analysed as a disordered structure over two states, viz. co-crystal and salt, accompanied by a keto-enol tautomerization in the base mol-ecule. The co-crystal is 4-chloro-2-nitro-benzoic acid-quinolin-4(1H)-one (1/1), C7H4ClNO4·C9H7NO, and the salt is 4-hy-droxy-quinolinium 4-chloro-2-nitro-benzoate, C9H8NO+·C7H3ClNO4 -. In the compound, the acid and base mol-ecules are held together by a short hydrogen bond [O⋯O = 2.4393 (15) Å], in which the H atom is disordered over two positions with equal occupancies. In the crystal, the hydrogen-bonded acid-base units are linked by N-H⋯O and C-H⋯O hydrogen bonds, forming a tape structure along the a-axis direction. The tapes are stacked into a layer parallel to the ab plane via π-π inter-actions [centroid-centroid distances = 3.5504 (8)-3.9010 (11) Å]. The layers are further linked by another C-H⋯O hydrogen bond, forming a three-dimensional network. Hirshfeld surfaces for the title compound mapped over shape-index and d norm were generated to visualize the inter-molecular inter-actions.

Highlights

Crystal structure of 4-chloro-2-nitrobenzoic acid with 4-hydroxyquinoline: a disordered structure over two states of 4-chloro-2-nitrobenzoic acid– quinolin-4(1H)-one (1/1) and 4-hydroxyquinolinium 4-chloro-2-nitrobenzoate
The hydrogen-bonded acid–base units are linked by N—HÁ Á ÁO and C—HÁ Á ÁO hydrogen bonds, forming a tape structure along the a-axis direction
In our previous study on D—HÁ Á ÁA hydrogen bonding (D = N, O, or C, A = N, O or Cl) in chloro- and nitro-substituted benzoic acid–pyridine derivative systems, we have shown that several compounds, namely, three compounds of quinoline with 3-chloro-2-nitrobenzoic acid, 4-chloro-2-nitrobenzoic acid and 5-chloro-2-nitrobenzoic acid (Gotoh & Ishida, 2009), two compounds of phthalazine with 3-chloro-2-nitrobenzoic acid and 4-chloro-2-nitorbenzoic acid (Gotoh & Ishida, 2011), and 3-chloro-2-nitrobenzoic acid–isoquinoline (Gotoh & Ishida, 2015), have a short double-well OÁ Á ÁHÁ Á ÁN hydrogen bond between the carboxy O atom and the aromatic N atom

Summary

Chemical context

Hydroxyquinolines, which have hydrogen-bond acceptor as well as donor groups, appear attractive as a base molecule in the above systems for investigating the hydrogen bonds (Babu & Chandrasekaran, 2014; Gotoh & Ishida, 2019). We report here the crystal structure of the title compound, in which there exists another type of short double-well hydrogen bond, namely, an OÁ Á ÁHÁ Á ÁO hydrogen bond between the acid and base molecules, accompanied by a keto–enol tautomerization of the base molecule. Symmetry codes: (i) x À 12; Ày þ 12; Àz þ 1; (ii) Àx þ 1; y; Àz þ 32

Structural commentary

Supramolecular features

Database survey

Synthesis and crystallization

Refinement