Molecular Architectonics of Stereochemically Constrained -Complementary Functional Modules

The elucidation of the complex factors that govern recognition events at the molecular level represents a daunting challenge in our quest to master the art of pre-programmed molecular assemblies. In this context, we present the molecular architectonics of thoughtfully designed amino acid appended functional molecules 1-5. Naphthalenediimide (NDI) and pyrene were employed as functional modules due to their unusual topological shape similarity as well as complementary -acidic and -basic character, respectively. In addition, we show that dyads of such unusual functional modules energetically favour alternate assembly in contrast to the predominant self-sorted assembly observed for single-component systems. Moreover, by incorporating minute structural mutations into the amino acid side-chains of 1-5, we successfully tailored their assemblies into well-defined supramolecular architectures, namely supercoiled helices, twisted nanoribbons, nanobelts, comb-edged nanoflakes and nanosheets. A detailed analysis with the aid of experimental and theoretical studies has generated interesting insights into the factors that govern the recognition events at the molecular level.