The influence of benzoate anion substituents on the crystal packing and hydrogen-bonding network of 9-aminoacridinium salts

As a continuation of our recent work, we discuss the crystal structures of a series of salts with the 9-aminoacridinium cation and 3-chlorobenzoate, 4-chlorobenzoate and 3-hydroxybenzoate anions. The crystal structure of [2(C13H11N2+)·C7H5O3−·Cl−·2(H2O)] is the first of all the known 9-aminoacridinium salts where mixed salts were obtained. Analysis of the hydrogen bonds in the crystal lattices of the title compounds shows that the ions are linked via N(amino)–H⋯O(carboxy) hydrogen bonds forming R22(8) or R24(16) hydrogen bond ring motifs. In the packing, there are also two kinds of hydrogen bond chain motif. The first, C42(16), in which 9-AA cations, a Cl− anion and a water molecule are interlinked, and the second, C(7), in which aromatic carboxylic acid anions are connected directly. We also observed the influence of the different anions on the packing of the acridine skeletons in the crystal lattice.

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