Complexes of Co(II), Ni(II) and Cu(II) with lapachol

Complexes of naturally occurring hydroxynaphtho-quinone, lapachol (2-hydroxy-3(3-methyl-2-buthenyl)-1,4-naphthoquinone = HL) with Co(II), Ni(II) and Cu(II) have been prepared by reaction of the corresponding acetates with the ligand (HL) in ethanol. The molecular and crystal structures were determined for [CoL2(EtOH)2] (1), [NiL2(EtOH)2] (2), and [CuL2(py)2] (3). In all cases the deprotonated lapachol behaves as chelating bidentate ligand. The complexes were also characterized by elemental analyses, cyclic voltammetry, and FAB-MS.

Graphical abstractThe complexes of naturally occurring hydroxynaphtho-quinone, lapachol (HL) with Co(II), Ni(II) and Cu(II) have been prepared and the crystal structures of [CoL2(EtOH)2], [NiL2(EtOH)2] and [CuL2(py)2] reported. Characterisation by elemental analyses, cyclic voltammetry and FAB-MS was also performed.Figure optionsDownload full-size imageDownload as PowerPoint slide