Pentacoordinated copper-sparteine complexes with chelating nitrite or nitrate ligand: Synthesis and catalytic aspects

► Penta-coordinated monomeric copper(II)-sparteine complexes. ► Chelating mode of nitrite or nitrate in copper(II)-sparteine complexes. ► Square pyramidal geometry of [Cu(sparteine)(Cl)(NO2)] and [Cu(sparteine)(Cl)(NO3)]. ► Selective catalytic epoxidation and oxidation processes.