Synthesis of quinoline and bis-quinoline derivatives is reported using nickel chloride hexahydrate catalyst via Michael addition followed by aldol condensation from α,β-unsaturated ketone and o-aminobenzyl alcohol. The protocol enables access to products in good to excellent yields in toluene at 100 °C and in open-air condition under green chemistry metrics of the reaction.

Two-component synthesis of quinoline and bis-quinoline derivatives using nickel chloride hexahydrate as a catalyst via Michael addition followed by aldol condensation from α,β-unsaturated ketone and o-aminobenzyl alcohol. This protocol enables access to phenyl(2-phenylquinolin-3-yl)methanone and bis(2-phenylquinolin-3-yl)methanone derivatives in good to excellent yields using toluene solvent at 100 °C temperature in open-air condition. Nickel chloride hexahydrate has been utilized in this study to oxidize benzyl alcohols to intermediate benzaldehydes. Green chemistry metrics of the reaction explain the dominance of the methodology. The structural characterization of the compounds was confirmed by ¹H, ¹³C, Infrared (IR), UV–vis spectroscopy, and high resolution mass spectrometry (HRMS) analysis.