Synthesis, Characteritation, Optoelectronic Properties and DFT Studies of Novel 4,5‐Diarylpyrazole‐1‐Carboxylates

Abstract

AbstractIn the present work, a well organised pathway for the eco‐friendly synthesis of a series of 4,5‐diarylpyrazole‐1‐carboxylates has been reported. The resulted compounds were characterized by different spectroscopic techniques (IR, 1H‐NMR & 13C‐NMR and HRMS). To shed light on various properties of interests, density functional theory (DFT) was utilized to optimize the ground state geometry of synthesized pyrazoles. Time dependent density functional theory (TDDFT) was used to investigate the impact of various functionals on the absorption wavelength i.e., B3LYP, M062X, BHandHLYP, B3P86, CAM‐B3LYP, and PBE0. Among all these functional, CAM‐B3LYP and BHandHLYP were in good consent with the experimental results. With an aim to enhance the optoelectronic properties, 10 new derivatives were designed by varying the various substituents on the aryl ring. Among all these synthesized pyrazole molecule, Methyl 4‐(4‐Methoxyphenyl)‐5‐(3‐nitrophenyl)‐1H‐pyrazole‐1‐carboxylate 3a and Methyl 4‐(4‐Methoxyphenyl)‐5‐(4‐nitrophenyl)‐1H‐pyrazole‐1‐carboxylate 3b exhibited better optoelectronic properties with HOMO‐LUMO gap of 3.38 eV. To the best of our knowledge, the studies of photophysical properties of these 1,4,5‐trisubstituted pyrazoles for optoelectronic uses has been reported first time by our research group.