Synthesis, DFT Calculations and Spectral Characterization of Novel Pyrimidine and Pyrazoline Derivatives

In this study, new pyrazole and pyridine derivatives bearing thiophene moieties have been prepared by condensing 1-(4-hydroxyphenyl)3-(thiophen-2-yl)prop-2-en-1-one 1 with different nitrogen and carbon nucleophiles such as hydrazine, guanidine hydrochloride afforded compounds 2 and 3. Reaction of hydrazine derivative 2 with carbon electrophile such as benzoyl chloride, chloroacetic acid and chloroacetyl chloride gave the corresponding pyrazol derivatives 4-6. Condensation of pyrimidine derivative 3 with cyclohexanone and dichlorobenzaldehyde gave shiff`s base 7 and 8. Elemental and spectroscopic evidence characterized all the newly synthesized compounds. The molecular electronic structures have been studied and computed with density function theory framework (DFT). We studied the electrophilicity of these compounds to determine the most active compound, which was compound 5.