SIDEROPHORES .2. TETRAZOLYL ENOLATE AND SEMICORRINATE ANIONS AS CHELATE LIGANDS FOR IRON(II) AND COPPER(II) IONS - FROM MOLECULAR TO COLLECTIVE STRUCTURES

Reaction of tetrazolyl enolate 2 (HL2) with Cu(II) acetate yields the 3D-coordination polymer 4 ([CuL2(2)]n), the structure of which is unequivocally established by single-crystal X-ray diffraction. The formation of 4 is understandable if 2 or its enolate is considered as tridentate chelate ligand and if an intermediate formation of the coordinatively unsaturated copper(II) building block 6 is assumed. The monomers 6 are bidentate coordinating by the two CN groups, which leads to linking o monomers and to coordinative saturation at the copper(II) center of 6 with formation of three-dimensional 4. Semicorrin 8 (HL4) , however, reacts with Fe(II) to give the exceptional mononuclear tetrahedral chelate complex 10 (X-ray). EPR and Mossbauer spectra of 4 and 10 are discussed.