Highly efficient phosphate diester hydrolysis and DNA interaction by a new unsymmetrical FeIIINiII model complex

A new heterodinuclear mixed valence complex [FeIIINiII(BPBPMP)(OAc)2]ClO4 1 with the unsymmetrical N5O2 donor ligand 2-bis[{(2-pyridylmethyl)-aminomethyl}-6-{(2-hydroxybenzyl)(2-pyridylmethyl)}-aminomethyl]-4-methylphenol (H2BPBPMP) has been synthesized and characterized. 1 crystallizes in the monoclinic system, space group P21/n, a=12.497(2), b=18.194(4), c=16.929(3) Å, β=94.11(3)°, V=3839.3(12) Å3 and has an FeIIINiII(μ-phenoxo)-bis(μ-carboxylato) core. Solution studies of 1 indicate that a pH-induced change in the bridging acetate occurs and the formation of an active [(OH)FeIII(μ-OH)NiII(OH2)]+ species as the catalyst for phosphate diester hydrolysis and DNA interaction is proposed. In addition, the results presented here suggest that NiII would be a good candidate as a substitute of MII in purple acid phosphatases.