Synthesis, crystal structure and solution behavior of a novel tetranuclear Zn(II) Schiff base complex

The tetranuclear Zn(II) Schiff base complex [Mg(H2O)6][{Zn2L1(CH3CO2)}2(μ3-OH)2]·6H2O (H3L1=Schiff base derived from 2,6-diformyl-4-methylphenol and glycine) (2) has been prepared and structurally characterized. The complex anion consists of two identical dinuclear Zn2/L1 subunits connected through μ3-OH bridges. While 2, with Mg(H2O)6 2+ serving as counterion, crystallized from aqueous solution, solution studies in DMSO indicated substitution of zinc by magnesium and formation of the heteronuclear complex [ZnMgL1]+.