Trimesic acid, crystal structure

Herbstein, F. H., Marsh, R. E., Crystal-Structures of Trimesic acid, its hydrates and complexes. 2. trimesic acid monohy-drate-2/9 picric acid and trimesic acid 5/6 hydrate. Acta Crystallogr. Sect. B-Struct. Commun. 1977, 33, 2358-2367. 

If a bulky hydrophobic group is introduced at the 5-position of isophthalic acid, a cyclic hexamer (rosette) is generated. In the crystal structure of trimesic acid, the voids are filled through interpenetration of two honeycomb... 

The complex between melamine and cyanuric acid (1 1) was reported in the literature in the late 1970s, but it was only in the early 1990s that the contributions from Whitesides and the concept of self-assembly popularized these systems [45]. Whitesides and co-workers reported the formation of tapes (Fig. 11.11), crinkled tapes and cyclic hexamers (rosettes) formed between barbituric acid and N,N -bis(p-substituted phenyl)melamine [46], In this they effectively blocked one face of melamine and, by manipulating substituents at the para position, different structures were obtained. Whiteside s putative suggestion that melamine/cyanuric acid formed an extended array (Fig. 11.12) was confirmed recently by Rao et al. with the crystal structure [47]. Hamilton and coworkers reported the crystal structure of a 5-substituted isophthalic acid derivative, which forms a cyclic aggregate held together with six pairs of hydrogen bonds, which in a way resembles the trimesic acid (Fig. 11.13) [48]. 

Duchamp, D. J. and Marsh, R. E. (1969). The crystal structure of trimesic acid (benzene-1,3,5-tricarboxylic acid). Acta Crystallogr. B25, 5. 

The advantage of using the synthon approach is that it offers a considerable simpHfication in the understanding of crystal structures. For example, the same carboxy dimer motif 1 is present in the structures of benzoic acid, terephthalic acid, isophthahc acid, trimesic acid and adamantane-l,3,5,7-tetracarboxylic acid in zero-, one-, two- and three-dimensional arrangements [9] (see also the article by R. E. Melendez and A. D. Hamilton in this volume). 

---