Synthesis and Characterization of some new Chalcones and Pyrazoline, Compounds

An , -Unsaturated carbonyl compounds as presented (chalcone derivatives) (1a-d) were prepared by Claisen-Schmidt condensation reaction by coupling Pyridine-4-carboxaldehyde with acetophenone, 4-methylacetophenone and 4-aminoacetophenone in alcoholic medium in the presence 5-10% an aqueous sodium hydroxide and with stirring at room temperature gives (1a-c) compounds. While compound (1d) was prepared by coupling 2-acetyl pyridine with benzaldehyde in an aqueous medium in the presence 10% aqueous sodium hydroxide and stirring at room temperature. The other step in this research to get the target compounds is the chalcones (1a-d) have been utilized for the preparation of several pyrazoline derivatives (2a-d and 3a-d) using two different reagents either, refluxing hydrazine hydrate (99%) and glacial acetic acid to give (2a-d), or thiosemicarbazide in presence sodium acetate as base and ethanol as solvent to give (3a-d). The chemical structures of all synthesized (1a-d, 2a-d and 3a-d) were established on the basis of some physical properties and some spectroscopy methods like, Fourier Transform-Infrared spectrum (FT-IR), Proton Nuclear Magnetic Resonance (1HNMR) and Carbon 13- Nuclear Magnetic Resonance (13C-NMR) spectra. Also, some of these reactions are followed by thin layer chromatography (TLC) technique and calculate the retardation factor (Rf) values.