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A disodium salt of azotetrazolate (SAZ) has been prepared and characterized by elemental, UV, 13C NMR, FT-IR, and crystallographic analyses. Single crystals of the pentahydrate were grown by slow evaporation of an aqueous solution under reduced pressure. The crystal structure of SAZ has been determined by X-ray diffraction. The crystal lattice is triclinic P1 (no. 2) with lattice parameters a=7.115(1)A, b=7.559(1)A, c=12.025(1)A, alpha=79.75(1) degrees , beta=81.12(1) degrees , gamma=68.16(1) degrees and V=587.97(12)A3. Explosion delay studies have been undertaken using the tube furnace technique. The thermal stability of the compound has been discussed in the light of TG-DSC and explosion delay.

Di- and tricatechol imines are easily accessible by condensation of appropriate amines with 2,3-dihydroxybenzaldehyde. Dicatechol imines can be used for the alkali metal template-directed self-assembly of dinuclear triple-stranded helicates or meso-helicates with high diastereoselectivity. Tricatechol imines lead in self-assembly processes to metallosupramolecular 4 [ratio] 4 tetrahedra with a huge internal cavity, which is able to encapsulate guest species. Hereby the special features of the imine unit can be used to control the outcome of the self-assembly process.

Dicatechol ligands 3b-g-H4 are simply prepared by imine formation of 2,3-dihydroxybenzaldehyde 2 with a series of different diamines 1b-g . An X-ray structural analysis was obtained for the butyl-bridged compound 3e-H4, showing an intramolecular proton transfer and the formation of a chinoidic "keto-amine" structure. The dicatechol derivatives 3b-g-H4 form dinuclear triple-stranded helicates M4[(3)3Ti2] with titanium(IV) ions in the presence of alkali-metal carbonate. For the phenyl- and the trans-1,4-cyclohexyl-bridged complexes, K4[(3b)3Ti2] and Na4[(3f)3Ti2], X-ray structures were obtained.

The self-assembly of supramolecular structures depends on a subtle interplay of a series of different control mechanisms. The geometric as well as electronic complementarity of the molecular building blocks is crucial for the specific formation of defined supramolecular species. In addition, secondary effects, like templating, also have an important function. The templating ability of different cations in the formation of triple-stranded helicate-type complexes from alkyl-bridged di(8-hydroxyquinoline) ligands is investigated by introduction of alkyl chains of different length as ligand spacers. Hereby a "size-selectivity" between the cations and the dinuclear helicate-type complexes [(ligand)(3)M(2)] is observed. Large cations support the formation of big dinuclear complexes, whereas small cations are able to template the formation of small complexes.