Polypyridyl multidentate ligands based on ethylenediamine backbones are important metal-binding agents with applications in biomimetics and homogeneous catalysis. The seemingly hexadentate tpena ligand [systematic name:N,N,N′-tris(pyridin-2-ylmethyl)ethylenediamine-N′-acetate] reacts with zinc chloride and zinc bromide to form trichlorido[μ-N,N,N′-tris(pyridin-2-ylmethyl)ethylenediamine-N′-acetato]dizinc(II), [Zn2(C22H24N5O2)Cl3], and tribromido[μ-N,N,N′-tris(pyridin-2-ylmethyl)ethylenediamine-N′-acetato]dizinc(II), [Zn2Br3(C22H24N5O2)]. One ZnIIion shows the anticipated N5O coordination in an irregular six-coordinate site and is linked by ananticarboxylate bridge to a tetrahedral ZnX3(X= Cl or Br) unit. In contrast, the CuIIions in aquatribromido[μ-N,N,N′-tris(pyridin-2-ylmethyl)ethylenediamine-N′-acetato]dicopper(II)–tribromido[μ-N,N,N′-tris(pyridin-2-ylmethyl)ethylenediamine-N′-acetato]dicopper(II)–water (1/1/6.5) [Cu2Br3(C22H24N5O2)][Cu2Br3(C22H24N5O2)(H2O)]·6.5H2O, occupy two tpena-chelated sites, one a trigonal bipyramidal N3Cl2site and the other a square-planar N2OCl site. In all three cases, electrospray ionization mass spectra were dominated by a misleading ion assignable to [M(tpena)]+(M= Zn2+and Cu2+).