Fluorescent Assembles of 2‐Amino‐3‐cyanothiophenes with Azoles. Design and Peculiar Properties of Absorption and Emission

Abstract Three new types of azolylthiophene fluorescent dyes, (1‐aryl‐1 H ‐1,2,3‐triazole‐4‐carbonyl)thiophenes (ATTs), (3‐arylisoxazole‐4‐carbonyl)thiophenes (AITs), 1‐aryl‐1 H ‐pyrazole‐4‐carbonyl)thiophenes (APTs), were synthesized by the 1,3‐dipolar cycloaddition reaction. All the synthesized luminophores exhibited blue emission with high quantum yields (QYs) and positive solvato(fluoro)chromism. Photophysical investigations established the role of the heterocyclic core, substituents, and their combinations for the azolylthiophenes emission. ATTs and AITs exhibited a decrease in QY in polar solvents, while APTs showed the largest QYs in DMSO and DMF. Solvato(fluoro)chromism was analyzed by using the Lippert‐Mataga equation. These results revealed that ATTs are the most sensitive to the environment interactions among the investigated compounds. Azolylthiophenes exhibited intense green emission in the solid state (up to 75.9%). The experimental work was supported by quantum chemical calculations.