9 pages ; International audience ; Three new closely-related diimine ligands, H4L1, H4L2 and H4L3, were prepared by the condensation of 1,4-diformyl-2,3-dihydroxybenzene (1) with two equivalents of 2-aminoethanol, 3-aminopropanol or 2-aminophenol, respectively. Three polynuclear complexes, [NiII7(H2L1)4(OAc)6(H2O)2]*5H2O (2*5H2O), [NiII6(H2L2)2(OAc)6(μ-OMe)2(H2O)2]*5H2O (3*5H2O) and [NiII12(L3)6(MeOH)7(H2O)3]*4H2O (4*4H2O), were prepared by reaction of the appropriate ligand with 1.50/1.75, 1.75/3.00 or 2.00 equivalents, respectively, of nickel(II) acetate tetrahydrate, in methanol. The crystal structures of these complexes are very different to one another, despite what initially appear to be relatively minor ligand modifications. While [NiII7(H2L1)4(OAc)6(MeOH)2]*7MeOH*4H2O possesses C2 symmetry and has a 4:7 L:M ratio, [NiII6(H2L2)2(OAc)6(μ-OMe)2(MeOH)2]*0.5MeOH*0.5H2O*Et2O and [NiII12(L3)6(MeOH)6.5(H2O)3.5]*solvent have no internal symmetry and have L:M ratios of 2:6 and 6:12, respectively. Two of the four ligands in [NiII7(H2L2)4(OAc)6(MeOH)2] are in similar planes, whilst the two remaining ligands are near perpendicular to these planes. The six ligands in [NiII12(L3)6(MeOH)6.5(H2O)3.5] adopt an offset grid-like arrangement with eight of the twelve metal ions at the intersections of the perpendicular, offset, ligands. In contrast, [NiII6(H2L2)2(OAc)6(μ-OMe)2(MeOH)2] features an [NiII4(OR)4] cubane core with wing tips of the remaining two nickel(II) ions. All three complexes were subsequently prepared in stoichiometric syntheses, in yields of 50% (2*5H2O), 48% (3*5H2O) and 62% (4*4H2O). The magnetic properties of 2*5H2O, 3*5H2O, 4*4H2O are consistent with intra-complex antiferromagnetic coupling dominating overall, and therefore all three complexes display low spin ground states.