Adamantane Annulation to Arenes: A Strategy for Property Modulation of Aromatic -Systems

Peripheral structural modifications of arenes are widelyused tocontrol or improve the optoelectronic properties, molecular assembly,and stability of aromatic & pi;-materials as well as to explorenew functions. However, known modifications are often tedious andcomplex; therefore, a simple yet powerful modification strategy isneeded. We discovered that annulation with a simple adamantane scaffoldexerts a significant impact on the properties, alignment, and stabilityof aromatic & pi;-systems. This unprecedented adamantane annulationwas achieved by a two-step transformation of metallated arenes and4-protoadamantanone, generating a range of adamantane-annulated arenes.Analysis of structural and electronic properties uncovered uniqueeffects of the process, such as high solubility and enhanced conjugation.The oxidation of adamantane-annulated perylenes produced strikinglystable cationic species with emission extended to the near-infraredregion. This simple property modulation of aromatic & pi;-systemswould not only create potentially ground-breaking & pi;-materialsbut also novel nanocarbon materials, such as diamond-graphenehybrids.