The interaction of di(2-picolyl)amine (1) and its secondary N-substituted derivatives, N-(4-pyridylmethyl)-di(2-picolyl)amine (2), N-(4-carboxymethyl-benzyl)-di(2-picolyl)amine (3), N-(4-carboxybenzyl)-di(2-picolyl)amine (4), N-(1-naphthylmethyl)-di(2-picolyl)amine (5), N-(9-anthracenylmethyl)-di(2-picolyl)amine (6), 1,4-bis[di(2-picolyl)aminomethyl]benzene (7), 1,3-bis[di(2-picolyl)aminomethyl]benzene (8) and 2,4,6-tris[di(2-picolyl)amino]triazine (9) with Ni(II) and/or Zn(II) nitrate has resulted in the isolation of [Ni(1)(NO3)2], [Ni(2)(NO3)2], [Ni(3)(NO3)2], [Ni(4)(NO3)2]·CH3CN, [Ni(5)(NO3)2], [Ni(6)(NO3)2], [Ni2(7)(NO3)4], [Ni2(8)(NO3)4], [Ni3(9)(NO3)6]·3H2O, [Zn(3)(NO3)2]·0.5CH3OH, [Zn(5)(NO3)2], [Zn(6)(NO3)2], [Zn(8)(NO3)2] and [Zn2(9)(NO3)4]·0.5H2O. X-ray structures of [Ni(4)(NO3)2]·CH3CN, [Ni(6)(NO3)2] and [Zn(5)(NO3)2] have been obtained. Both nickel complexes exhibit related distorted octahedral coordination geometries in which 4 and 6 are tridentate and bound meridionally via their respective N3-donor sets, with the remaining coordination positions in each complex occupied by a monodentate and a bidentate nitrato ligand. For [Ni(4)(NO3)2]·CH3CN, intramolecular hydrogen bond interactions are present between the carboxylic OH group on one complex and the oxygen of a monodentate nitrate on an adjacent complex such that the complexes are linked in chains which are in turn crosslinked by intermolecular offset π–π stacking between pyridyl rings in adjacent chains. In the case of [Ni(6)(NO3)2], two weak CH⋯O hydrogen bonds are present between the axial methylene hydrogen atoms on one complex and the oxygen of a monodentate nitrate ligand on a second unit such that four hydrogen bonds link pairs of complexes; in addition, an extensive series of π–π stacking interactions link individual complex units throughout the crystal lattice. The X-ray structure of [Zn(5)(NO3)2] shows that the metal centre once again has a distorted six-coordinated geometry, with the N3-donor set of N-(1-naphthylmethyl)-di(2-picolyl)amine (5) coordinating in a meridional fashion and the remaining coordination positions occupied by a monodentate and a bidentate nitrato ligand. The crystal lattice is stabilized by weak intermolecular interactions between oxygens on the bound nitrato ligands and aromatic CH hydrogens on adjacent complexes; intermolecular π–π stacking between aromatic rings is also present.