Network formation of mellitate anions ([C6(COO)6H6−n]n−) in the salts with piperidinium derivatives and o-phenylenediammonium

Abstract

Single crystals of mellitate anion ([C6(COO)6H6−n]n−) with piperidinium [C5H10NH2+]3[C6(COO)6H33−] (1) and [C5H10NH2+]2[C6(COO)6H42−]·CH3OH·3H2O (2), with 1-methylpiperidinium [C5H10NHCH3+]2[C6(COO)6H42−]·2H2O (3), and with o-phenylenediammonium [C6H4(NH3)22+]2[C6(COO)6H24−]·2CH3OH (4) have been prepared and structurally characterized. In all of the salts, two-dimensional (2D) networks of mellitate anions were formed due to the strong self-organization of the anion. In 1, a 2D hexagon-type network of hydrogen-bond has been observed to form among the anions. This is characteristic of the mellitate anions with n = 3 (n: deprotonation number from the acid). In other salts, a 2D anion network containing either water molecules or –NH3 groups commonly formed. Since the network pattern occurs with different cation species, this hydrogen-bonding unit was determined to be dominant in the n = 2 anion with water and the n = 4 anion with –NH3 species.