A Systematic Study on the Synthesis of n-Butyl Substituted 8-Aminoquinolines

A systematic study on the synthesis of 8-aminoquinoline derivatives with an n-butyl group at each alternate position of the quinoline ring was carried out. Skraup Reaction and its Doebner-von Miller variation were used to obtain most of the quinoline ring except for the 2-butyl-8-aminoquinolines and 4-butyl-8-aminoquinolines where the commercially available methylquinoline derivatives were used as precursors. The structures of the synthesized compounds were characterized by FTIR, H-1-NMR, COSY, C-13-NMR and HRMS spectra.