A few 1,8-naphthalimide derivatives with phenyl (1), benzyl (2), 3,4-dimethoxyphenyl ethyl (3), 4-pyridyl (4), 2-hydroxy ethyl (5), 4-pyridylmethyl (6) groups attached to the nitrogen atom are synthesized and characterized. Cyclic voltammograms of all these compounds show one-electron reversible redox cycle ( −1·24 V to −1·18 V) due to formation of anion radicals. However, in the case of (5), quenching of this redox process occurs when polyhydroxy-aromatic compounds such as 1,3-dihydroxy benzene and 1,3,5-trihydroxybenzene are added. Copper complexes, namely bis-{N-(4-pyridylmethyl)1,8-naphthalimide} copper (II) perchlorate (8), bis-{N-(4-pyridylmethyl)1,8-naphthalimide}copper (II) perchlorate (9) and bis-{N-(4-pyridylmethyl)phthalimide} copper (II) perchlorate (10) are synthesized and characterised. The complexes (8) and (9) show reversible redox couple of the ligand without any significant interaction with the redox active copper (II) centre.

Different hydrogen bonded dimeric motifs of 3-carboxyphenoxyacetic acid (H2cpa) observed inthe self-assemblies of salts or cocrystals of H2cpa with nitrogen containing compounds are discussed. Pyridiniumsalt of the H2cpa is a self-assembly of Hcpa with the pyridinium cation. The assembly is a combinationof sub-assemblies of two Hcp anions with two pyridinium cations, in which the Hcpa cations are interconnectedthrough carboxylate-carboxylic acid interactions. The cocrystals of H2cpa with isoquinoline or isonicotinamideare self-assemblies of hydrogen bonded dimers of H2cpa holding the respective guest molecule.However, the dimeric assemblies of H2cpa in these two cases are different from each other; the former cocrystalhas carbony-hydroxyl type interactions in it whereas the latter cocrystal has unconventional dimeric subassembliesof H2cpa with hydroxyl-hydroxyl type hydrogen bond interactions. The cocrystal of H2cpa withtheophylline has sub-assemblies of two H2cpa molecules interacting with two theophylline guest molecules,where the theophylline molecules are hydrogen bonded in two different ways.

Various non-covalently linked inorganic self-assemblies formed by the supramolecular interacting sites located at the ligands are discussed. The impetus for this rapidly growing topic on the construction of robust assemblies is elucidated by select examples that are associated with interesting structures and properties. The review includes discussion on the stabilization of different assemblies of nucleobases in the non-covalent assemblies of inorganic complexes. The participation of the guest molecules in the formation of self-assemblies with hosts to make extra space or voids for intake of the guest, water-assisted assemblies, changes in the structures guided by cations, and aggregation-induced photoluminescence in the self-assemblies of metal complexes are presented. Fine-tuning of non-covalent self-assemblies of metal complexes by changing ligands or by other components, which modify the guest recognition abilities is elucidated. The discussions are based on selected examples of self-assemblies that use supramolecular features of peripheral part of ligands or ligand of a complex that helps one to identify templates for weak interactions and for molecular recognition.