Iron(III) Tris(pyridinehydroxamate)s and Related Nickel(II) and Zinc(II) Complexes: Potential Platforms for the Design of Novel Heterodimetallic Supramolecular Assemblies

Abstract The reaction of 3‐ and 4‐pyhaH (pyhaH = pyridinehydroxamic acid) with hydrated metal salts (Fe III , Ni II , Zn II ) in aqueous solution affords tris(pyridinehydroxamate)s in the case of Fe III and bis(pyridinehydroxamate)s in the case of Zn II and Ni II in both the solid state and in solution. These metal pyridinehydroxamates that have the hydroxamato moiety coordinated in an O,O′‐bidentate fashion all contain free pyridine nitrogen donor atoms that might allow them to be used as building blocks in the construction of pyridinehydroxamato‐bridged supramolecular assemblies. The crystal and molecular structures of the two novel Fe III tris(pyridinehydroxamate) building blocks [Fe III (3‐pyha) 3 ] · 5.125H 2 O ( 1a ) and [Fe III (4‐pyha) 3 ] · 5.5H 2 O ( 2a ) are found to have different packing systems despite the similar nature of the two complexes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)