Copper(I) with d 10 electronic configuration is well known for its tetrahedral coordination geometry and the wide range of application of its complexes. 2-substituted benzothiazoles have attracted considerable interest due to their diverse biological and pharmaceutical properties such as antimicrobial, antivirial, anticancer and enzyme inhibitory activity. The unsymmetrical bidentate ligand 2-quinoline benzothiazole (qbtz) was prepared from 2-aminothiophenol and quinaldic acid by an efficient and benign method recently developed in our laboratory, using triphenylphosphite (TPP) in the presence of the inexpensive ionic liquid tetrabutylammonium bromide (TBAB) as reaction medium. Three new copper(I) complexes of qbtz have been synthesized and characterized by elemental analyses, IR, UV–Vis, and 1 H NMR spectroscopy. 1) [Cu(qbtz)(PPh 3 )Br] 2) [Cu(qbtz)(PPh 3 )I] 3) [Cu(qbtz)(dppe)]ClO 4 The complexes (1) and (2) were structurally characterized by X-ray Diffraction. The electrochemical behavior and antibacterial activities of the ligand and its copper(I) complexes has been investigated and compared with the antibiotic penicillin. The catalytic activity of these complexes in one type of click reaction has also been studied and reported.