Synthesis, Characterization and Structural Optimization Using Density Functional Theory of Hydrazone Schiff Base Derivatives

Abstract

This thesis paper is related in an effective method for the addition of 2,4-dinitrophenyl hydrazine and various substituted 2,6-dibenzylidene cyclohexanone based bis-chalcones in the presence of hydrochloric acid to produce various hydrazone Schiffbase derivatives. First product, N[2,6bis(4:chlorobenzylidene)cyclohexylidene]-N'-(2,4-dinitrophenyl)-hydrazine has been synthesized by the reaction of 2,4-dinitrophenyihydrazine with 2,6-bis-(4-chlorobenzylidene)-cyclohexanone at reflux conditionat 2 hours. The isolated product was red in color and the melting point of the pure product was 185 °C. Second synthesized product. N-[2,6-bis-(4-methoxy-benzylidene)-cyclohexylidene]-N'-(2,4-dinitrophenyi)-hydrazifle has been synthesized by the reaction of 2,4-dinitrophenyl hydrazine with 2,6-bis-(4-methoxybenzylidene)-cyclohexanone at the same condition. The pure product was coffee color and the melting point of the pure product was 225 °C. Final product, N-[2,6-bis-(4-dirnethylamino-benzylidene)-cyclohexylidene]-N'-(2,4-dinitrophenyl)-hydrazifle has been synthesized by the reaction of 2,4-dinitrophenyihydrazine with 2,6-bis-(4-dimethylbenzylidene)-cyclohexanone also at the same condition. The product of the color was black and the melting point of the pure product was 245 °C. The structures of the synthesized products were characterized by their physical, UV, FTIR, 'H NMR & '3C NMR spectra. Their optimized structures have been investigated by computational method, Gaussian 16 software Revision B.01. Their molecular geometry and vibrational frequencies were computed at density functional theory, DFT-133LYP/6-3 1 1+G (2d, p) level of theory.