Role of pKa in establishing crystal structures of six hydrogen-bonded compounds of with different isomers of chloro- and nitro-substituted benzoic acids was written by Ishida, Hiroyuki. And the article was included in Acta Crystallographica, Section E: Crystallographic Communications in 2021.Category: chlorides-buliding-blocks This article mentions the following:
The structures of the six hydrogen-bonded 1:1 compounds of 4-methylquinoline (C10H9N) with chloro- and nitro-substituted benzoic acids (C7H4ClNO4), namely, 4-methylquinolinium 2-chloro-4-nitrobenzoate, C10H10N+·C7H3ClNO4-, (I), 4-methylquinoline-2-chloro-5-nitrobenzoic acid (1/1), C10H9N·C7H4ClNO4, and (II), 4-methylquinolinium 2-chloro-6-nitrobenzoate, C10H9.63N0.63+·C7H3.37ClNO40.63-. The (III), 4-methylquinolinium 3-chloro-2-nitrobenzoate, C10H9.54N0.54+·C7H3.46ClNO40.54-, (IV), 4-methylquinolinium 4-chloro-2-nitrobenzoate, C10H10N+·C7H3ClNO4-, (V), and 4-methylquinolinium 5-chloro-2-nitrobenzoate, C10H10N+·C7H3ClNO4-, have been determined at 185-190 K. In each compound, the acid and base mols. are linked by a short hydrogen bond between a carboxy (or carboxylate) O atom and an N atom of the base. The O···N distances are 2.5652 (14), 2.556 (3), 2.5485 (13), 2.5364 (13), 2.5568 (13) and 2.5252 (11) Å, resp., for compounds (I)-(VI). In the hydrogen-bonded acid-base units of (III) and (IV), the H atoms are each disordered over two positions with O site:N site occupancies of 0.37 (3):0.63 (3) and 0.46 (3):0.54 (4), resp., for (III) and (IV). The H atoms in the hydrogen-bonded units of (I), (V) and (VI) are located at the N-atom site, while the H atom in (II) is located at the O-atom site. In all the crystals of (I)-(VI), π-π stacking interactions between the quinoline ring systems and C-H···O hydrogen bonds are observed Similar layer structures are constructed in (IV)-(VI) through these interactions together with π-π interactions between the benzene rings of the adjacent acid mols. A short Cl···Cl contact and an N-O···π interaction are present in (I), while a C-H···Cl hydrogen bond and a π-π interaction between the benzene ring of the acid mol. and the quinoline ring system in (II), and a C-H···π interaction in (III) are observed Hirshfeld surfaces for the title compounds mapped over dnorm and shape index were generated to visualize the weak intermol. interactions. In the experiment, the researchers used many compounds, for example, 2-Chloro-6-nitrobenzoic acid (cas: 5344-49-0Category: chlorides-buliding-blocks).
2-Chloro-6-nitrobenzoic acid (cas: 5344-49-0) belongs to organic chlorides. Chlorinated organic compounds are found in nearly every class of biomolecules and natural products including alkaloids, terpenes, amino acids, flavonoids, steroids, and fatty acids.While alkyl bromides and iodides are more reactive, alkyl chlorides tend to be less expensive and more readily available. Alkyl chlorides readily undergo attack by nucleophiles.Category: chlorides-buliding-blocks
Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics