Crystal structure characterization as well as theoretical study of spectroscopic properties of novel Schiff bases containing pyrazole group

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 95; pp. 135 - 142
• Main Authors: Guo, Jia, Ren, Tiegang, Zhang, Jinglai, Li, Guihui, Li, Weijie, Yang, Lirong
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 01-09-2012
• Subjects: Absorption; Characterization; Crystal structure; Crystallography, X-Ray; Models, Molecular; Models, Theoretical; Molecular Conformation; Pyrazole; Pyrazoles - chemical synthesis; Pyrazoles - chemistry; Schiff base; Schiff Bases - chemical synthesis; Schiff Bases - chemistry; Spectrometry, Fluorescence; Spectrophotometry, Ultraviolet; Spectroscopic properties; Theoretical study; Schiff base; Characterization; Spectroscopic properties; Theoretical study; Pyrazole; Crystal structure
• ISSN: 1386-1425; 1873-3557
• DOI: 10.1016/j.saa.2012.04.065

A series of novel Schiff bases containing pyrazole group were synthesized using 1-aryl-3-methyl-4-benzoyl-5-pyrazolone and phenylenediamine as the starting materials. The ultraviolet-visible light absorption spectra and fluorescent spectra of various as-synthesized products were measured. Moreover, the B3LYP/6-1G(d,p) method was used for the optimization of the ground state geometry of the Schiff bases; and the spectroscopic properties of the products were computed and compared with corresponding experimental data based on cc-pVTZ basis set of TD-B3LYP method. [Display omitted]
► A series of novel Schiff bases containing pyrazole group were synthesized and characterized. ► The UV–Vis spectra and fluorescent spectra of various as-synthesized products were measured. ► The B3LYP/6-31G(d,p) method was used for the optimization of the ground state geometry of the Schiff bases. ► The spectroscopic properties of the Schiff bases were computed based on cc-pVTZ basis set of TD-B3LYP method.
A series of novel Schiff bases containing pyrazole group were synthesized using 1-aryl-3-methyl-4-benzoyl-5-pyrazolone and phenylenediamine as the starting materials. All as-synthesized Schiff bases were characterized by means of NMR, FT-IR, and MS; and the molecular geometries of two Schiff bases as typical examples were determined by means of single crystal X-ray diffraction. In the meantime, the ultraviolet-visible light absorption spectra and fluorescent spectra of various as-synthesized products were also measured. Moreover, the B3LYP/6-1G(d,p) method was used for the optimization of the ground state geometry of the Schiff bases; and the spectroscopic properties of the products were computed and compared with corresponding experimental data based on cc-pVTZ basis set of TD-B3LYP method. It has been found that all as-synthesized Schiff bases show a remarkable absorption peak in a wavelength range of 270–370nm; and their maximum emission peaks are around 344nm and 332nm, respectively.