Synthesis Of C₇₀ Fragment Buckybowls And Their Device Properties

The research on condensed aromatic hydrocarbons with twisted aromatic molecular skeletons,which is compared with one-dimensional and two-dimensional materials.It is still less,because the curved fused-ring aromatic hydrocarbons have a curvedπ-πconjugated system,so they show very unique characteristics in many aspects,such as:optics,electronic devices,magnetism,and supramolecular chemistry.The synthesis and properties of curved condensed aromatic hydrocarbons are of great significance.Although there are many reports in the literature,there are few studies on the performance of organic semiconductor devices involving fullerene fragments.This paper mainly reports on the synthesis strategies of fullerene fragments substituted with different substituents and the study of device performance of substituted Buckybowls as organic semiconductors.The results reflect the effects of different substituents on the molecular packing mode,optoelectronic properties and performance of organic field effect transistors of Buck bowl molecules.The main research contents are as follows:1.Using 1,5-dichloroanthraquinone as raw material,p-trifluoromethylphenyl substituted Buckybowls were obtained through multi-step nucleophilic addition reaction,dehydroxylation aromatization and palladium-catalyzed carbon-carbon coupling reaction.Its optical and electrical properties are similar to those reported for 2,4,6-triisopropylphenyl-substituted Buck bowl molecules,but the single-crystal arrangement is significantly different.It is mainly manifested as the strong interaction between the convex surface and the convex surface different from the 2,4,6-triisopropylphenyl substituted Buckybowl.The charge carrier can be transported efficiently through the curved surface,and the carrier mobility of the organic field effect transistor as an organic semiconductor layer reaches 1×10^-2cm²·V^-1·s^-1.2.Also using 1,5-dichloroanthraquinone as raw material,through nucleophilic addition reaction,dehydration rearrangement reaction,reduction and bromination of aromatic ketone carbonyl,important intermediate brominated aromatic hydrocarbons are obtained,and then pass through Sonogashira carbon-carbon respectively.Coupling reaction and Suzuki carbon-carbon coupling reaction were used to obtain three kinds of substituent-substituted bowl-shaped compound precursors,and finally three kinds of Buckybowl molecules substituted with different substituents were obtained by palladium-catalyzed coupling reaction.Its optical and electrical properties show that the silynyl-substituted Buck bowl molecules show a significant red shift compared to 2,4,6-triisopropylphenyl-substituted bowl molecules.However,the pyridine heterocycle substituted Buckybowl showed a slight blue shift,and the CV curve showed an irreversible oxidation peak.The mixed crystal of it and C₇₀ showed that the overall ratio is 1:1.The carrier mobility of a single crystal of pyridine-substituted Buck bowl molecules as the active layer of an organic field effect transistor is 3×10^-2 cm²·V^-1·s^-1.