Fine Tuning of Optical and Electrochemical Properties of peri-Functionalized Naphthalene Dyes Using Non-Covalent Interactions

Abstract

This research explores the potential of peri-functionalized naphthalene dyes, focusing on the unique "proximity effect" that allows for the development of versatile molecules with fascinating optical and electrochemical properties. The study highlights novel derivatives of Naphthalene Diimide (NDI), such as aImPyDI and bImPyDI, showcasing cation-mediated tuning of their optical and electrochemical behaviors. These derivatives exhibit rare properties such as vibronically fine NIR absorption and emission, high quantum yields due to the absence of TICT phenomena, and negative halochromism. The research underscores the role of metal ion coordination in stabilizing electrogenerated dianions, presenting applications in energy storage and organic electronics. Building on this foundation, perimidinium imide (PrIm), an ambipolar naphthalene-based molecule, was synthesized with unique self-assembly properties influenced by solvent environments. The study reveals surprising phenomena, such as supramolecular reassembly in the excited state of EhPrIm and the folding-unfolding behavior of alkyl chains, which lead to pathway complexity mimicking amyloid fibrils. These findings indicate that solvent composition and molecular interactions drive distinct aggregation states, offering insights into advanced supramolecular engineering. Additionally, the research identifies potential applications for these dyes in areas like OLED materials, OFETs. The study concludes by suggesting future explorations of modified derivatives through anion substitution and core functionalization to further expand their utility. This work contributes a versatile new building block to the field of smart molecule development.