The new Cu(I) complex [Cu(PNP NTPh-Ph)Cl] (1) containing the tridentate PNP pincer ligand N,N'-bis(diphenylphosphino)-2,6diamino-4-phenyl-1,3,5-triazine was obtained from the reaction of [Cu(SMe 2)Cl] n with the ligand as ether solvate 1. 0.5Et 2 O. 1 was independently obtained from a reaction mixture containing the ligand and the Cu(II) precursor CuCl 2. 2H 2 O in 50 % yield alongside with the Cu(II) coordination polymer [Cu(O 2 PPh 2) 2 ] n (2). From the reaction of Cu(NO 3) 2 • 3H 2 O with PNP NTPh-Ph in the presence of pyridine the complexes [Cu(O 2 PPh 2) 2 (Py) 2 (H 2 O)] (3), [Cu(O 2 PPh 2)(Py) 2 (NO 3)] 2 (4), and [Cu(Py) 4 (NO 3) 2 ]. Py (5), were obtained, 2, 3, and 4 contain diphenyl-phosphinate ligands. The underlying redox reaction of the ligand and Cu(II) yielding the oxidised ligands observed in the by-products and the Cu(I) product complex was further studied using electrochemistry and UV-vis spectroelectrochemistry. Attempts to synthesise the Cu(II) complex [Cu(PNP NTPh-Ph)(NO 3) 2 ] (6) in a mechanochemical experiment gave evidence for this unprecedented species from ESI-MS(+) and EPR spectroscopy but also revealed its very high sensitivity to air and moisture. The catalytic activity of 1 was investigated in the azide-alkyne cycloaddition yielding various 1-benzyl-4-phenyl-1H-1,2,3-triazoles. The environmentally benign ("green") and cheap EtOH/H 2 O solvent mixture turned out to be very suitable. Melting points, FT-IR, and NMR spectra of the triazole products were analysed.