Adducts of meso and racemic 5,5,7,12,12,14-hexamethyl-1,4,8, 11-tetraazacyclotetradecane with trigonally trisubstituted benzene carboxylic acids: supramolecular structures in one and two dimensions

The meso and racemic forms of 5,5,7,12,12,14-hexamethyl-1,4,8, 11-tetraazacyclotetradecane, C(16)H(36)N(4) (tet-a and tet-b, respectively), form adducts with trigonally trisubstituted benzene carboxylic acids; tet-a-3,5-dinitrobenzoic acid (1/2) (1), tet-a-5-hydroxyisophthalic acid-water (1/1/1) (3) and tet-b-5-hydroxyisophthalic acid-water (1/1/1) (4) are all salts, [C(16)H(38)N(4)](2+).2[C(7)H(3)N(2)O(6)](-) (1) and [C(16)H(38)N(4)](2+).[C(8)H(4)O(5)](2-).H(2)O (3) and (4). The conformations of the [(tet-a)H(2)](2+) and [(tet-b)H(2)](2+) cations are entirely different: [(tet-a)H(2)](2+) is precisely centrosymmetric in (1) and approximately so in (3), while [(tet-b)H(2)](2+) has approximate C(2) symmetry in (4). In each salt the cation forms two intramolecular N-H.N and four intermolecular N-H.O hydrogen bonds. In (1) the supramolecular structure is one-dimensional, a C(2)(2)(13)[R(2)(4)(16)] chain of rings. Compounds (3) and (4) crystallize in space groups P2(1)2(1)2(1) and P2(1)/c, respectively, but the supramolecular structures are very similar: in each, the anions and the water molecules form a C(7)[R(3)(3)(13)] chain of rings, generated in (3) by a 2(1) axis and in (4) by a glide plane. These chains are linked, in both (3) and (4), by cations to form sheets. Adjacent meso cations in (3) are related by a 2(1) axis and adjacent chiral cations in (4) are related by a glide plane.