X-Ray diffraction and magnetic studies on a series of isostructural divalent metal chloranilates with zigzag polymeric chain structures and on a dinuclear iron(in) chloranilatef

Abstract

The reaction of iron(m) ion with chloranilic acid (2,5-dichloro-3,6-dihydroxycyclohexa-2,5-diene-l,4-dione) in hot aqueous solution in air generated a product in which the iron, surprisingly, is in the -Hi oxidation state as is indicated by structural, magnetic and Mössbauer spectral studies. Single crystal X-ray studies of the product of composition [Fe(C6Cl2O4)(H2O)2]H 2O reveal a 1-dimensional zigzag polymeric structure with iron(n) ions carrying two cis water ligands linked together by bridging chloranilate anions. Hydrogen bonding between lattice water and the chains, together with close stacking of C6Cl2 units from adjacent chains, leads to a very compact 3-dimensional network. The sam..