Synthesis, Molecular Structure and Antioxidant Activity of (E)-4-[Benzylideneamino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one, a Schiff Base Ligand of 4-Aminoantipyrine |
| |
Authors: | Mohammad Sayed Alam Dong-Ung Lee |
| |
Institution: | (1) Division of Bioscience, Dongguk University, Gyeongju, 780-714, Republic of Korea;(2) Department of Chemistry, Jagannath University, Dhaka, 1100, Bangladesh |
| |
Abstract: | Abstract In this study, the title compound, C18H17N3O (M
r = 291.35), was synthesized by the condensation reaction of 4-amino-1,5-dimethyl-2-phenylpyrazole-3-one and benzaldehyde.
Single-crystal X-ray diffraction data revealed that this compound adopts a trans configuration around the central C=N double bond. It crystallizes in the monoclinic, space group P21/c with a = 12.9236(17) ?, b = 6.8349(9) ?, c = 17.072(2) ?, β = 90.316(3)°, V = 1508.0(3) ?3, Z = 4, D
c = 1.283 Mg/m3, F(000) = 616, μ = 0.082 mm−1, R = 0.0442, and wR = 0.0936. Two different planes exist within the molecule; e.g. the pyrazolone and benzylidene groups attached to C9 of the
pyrazolone ring are almost coplanar, whereas the phenyl group attached to the N1 of the pyrazolone ring is in another plane.
Density functional theory (DFT) and time-dependent DFT calculations were performed to predict the electronic structure and
absorption spectra of (E)-4-benzylideneamino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one, a schiff base ligand of 4-aminoantipyrine using B3LYP/6-311G basis set on the AM1 optimized geometry. The predicted
vibrational frequencies using the B3LYP/6-311G method were in strong agreement with the experimental IR spectra. The time
dependent DFT calculations were used to evaluate the electronic absorption spectrum and three electron transition bands, which
were mainly derived from the contribution of n → π* and π → π* transitions, were observed in both the experimental and predicted UV–Vis spectra. A maximum emission band
at 370 nm was observed in the fluorescence spectra of the title compound. In addition, the title compound showed good DPPH
antioxidant activity. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|