Thiazole-linked π-conjugated frameworks synthesized via sequential Pd-catalyzed arylation: synthetic strategy and structure–property correlations

), extensive solvatochromic responses, and red-shifted, tunable emission extending into the green-yellow region (420-550 nm). The Lippert-Mataga and Bilot-Kawski analyses confirmed pronounced excited-state dipole reorganization in representative compounds such as 4b, 4j, 4m, and 4q, thereby identifying them as sensitive, polarity-responsive fluorophores. Conversely, anthracene-substituted thiazoles, despite their intense absorption, showed low quantum yields. Overall, this work demonstrates the strategic utility of Pd-catalyzed sequential arylation in accessing a versatile library of thiazole fluorophores. By integrating synthesis, photophysical and solvatochromic studies, and DFT analysis, we validate thiazole as a versatile π-bridge scaffold with significant potential for OLEDs, laser dyes, and fluorescence sensing platforms.