Supramolecular Architectures Constructed from Piperazine and Substituted Benzoic Acids

Abstract

Piperazine (pip) were reacted with benzoic acid (Hba) and different substituted benzoic acid, such as o-chlorobenzoic acid (Hocba), m-chlorobenzoic acid (Hmcba), p-chlorobenzoic acid (Hpcba), o-aminobenzoic acid (Hoaba), p-aminobenzoic acid (Hpaba), affording a series of compounds [H2pip][ba]2 (1), [H2pip][ocba]2 (2), [H2pip][mcba]2 (3), [H2pip][pcba]2 (4), [H2pip][oaba]2 (5), and [H2pip][paba]2 (6). Extensive N–H···O hydrogen bonds are found in 1–6, featuring different hydrogen-bonding motifs. Compounds 1–4 have two-dimensional layers stabilized by strong N–H···O hydrogen bonds, while compounds 5 and 6 exhibit one-dimensional ribbons formed by N–H···O hydrogen bonds. Moreover, in compound 6, the existence of water molecules extends the one-dimensional ribbons into a three-dimensional supramolecular structure via hydrogen bonds. CCDC: 672374, (1); 672375, (2); 672376, (3); 672377, (4); 672378, (5); 672379, (6). The molecular self-assembly of piperazine (pip) with benzoic acid (Hba), o-chlorobenzoic acid (Hocba), m-chlorobenzoic acid (Hmcba), p-chlorobenzoic acid (Hpcba), o-aminobenzoic acid (Hoaba), and p-aminobenzoic acid (Hpaba) results in six new supramolecular networks 1-6, respectively.