Akademik Veri Yönetim Sistemi
JOURNAL OF MOLECULAR STRUCTURE, sa.1358, ss.1-10, 2026 (SCI-Expanded, Scopus)
In this study, chalcone derivatives with an antipyrine (phenazone) unit were synthesized via Claisen–Schmidt condensation of 4-antipyrinecarboxaldehyde with acetophenone derivatives. The structures of the compounds were confirmed by FT-IR, NMR, and HRMS analyses. FT-IR spectra showed the characteristic bands of the conjugated chalcone system together with substituent-dependent signals, while ¹H and ¹³C NMR data verified the α,β-unsaturated framework and the successful incorporation of functional groups. HRMS measurements showed [M+H]⁺ ions in close agreement with the calculated exact masses (≤1.78 ppm). UV-Vis spectra revealed π–π* transitions between 359-392 nm, with the nitro-substituted derivative exhibiting the largest bathochromic shift and band broadening. Fluorescence measurements indicated weak emission for all compounds. Complementary DFT/TD-DFT calculations reproduced the experimental trends and provided detailed insight into frontier molecular orbitals, oscillator strengths, and natural transition orbital (NTO) based electron-hole distributions. Global reactivity descriptors further established substituent-governed variations in electronic structure. The results reveal the structural and electronic features of antipyrine-derived chalcones and identify 4-antipyrinecarboxaldehyde as a versatile precursor for diverse conjugated systems.