Synthesis, Characterization, and DFT Calculations of Quinoline and Quinazoline Derivatives

Abstract

Treatment of 3-methylcyclohexanone with ethyl formate in the presence of sodium methoxide afforded sodium (2-methyl-6-oxocyclohexylidene)methanolate which reacted with aminopyrazoles, aminotriazole, and aminotetrazole to produce fused quinazoline derivatives; its reactions with cyanothioacetamide, cyanoacetamide, and cyanoacetohydrazide gave tetrahydroquinoline-3-carbonitrile derivatives. The reactions of 8-methyl-2-sulfanyl-5,6,7,8-tetrahydroquinoline-3-carbonitrile with alkylating agents led to the formation of thieno[2,3-b]quinoline derivatives. DFT computational studies of the synthesized compounds were carried out using B3LYP/6−311+G** and HF/6−311+G** approximations. The calculated HOMO and LUMO energies showed that charge transfer occurs in their molecules.