The efficient synthesis of N-fused coronene analogs and a related polyimide with near-infrared absorption

Abstract

A novel technique to synthesize N-fused coronene analogs was developed using the conventional thermal cycloaddition of perylene diimide with several 1,2,4-triazoline-3,5-diones. The cycloaddition occurred twice, primarily yielding a bis-adduct under optimized reaction conditions. 1H-nuclear magnetic resonance spectroscopy confirmed the transformation of the perylene unit with a polyimide backbone to a N-fused coronene unit. The N-fused coronene derivatives exhibited a wide absorption range from 600 to 850 nm and a low band gap of 1.3 eV. N-fused coronene analogs were prepared through thermal cycloaddition of perylene diimide with 1,2,4-triazoline-3,5-diones. Cycloaddition occurs twice, yielding mainly a bis-adduct under optimized reaction conditions using an oxidant. A perylene unit within a polyimide backbone transformed to a N-fused coronene unit with a wide absorption range from 600 to 850 nm and a low band gap of 1.3 eV.