H-bond supported coordination polymers of transition metal sulfites with different dimensionalities

Three novel transition metal–sulfite coordination complexes are synthesized using different amines and the role of H-bonding to provide structures with different dimensionalities are discussed.

3d-Metal derivatives of the [Cu(I)(SO3)4]7- ion: structure and magnetism

The Cu(SO(3))(4)(7-) anion, which consists of a tetrahedrally coordinated Cu(I) centre coordinated to four sulfur atoms, is able to act as a multidentate ligand in discrete and infinite supramolecular species. The slow oxidation of an aqueous solution of Na(7)Cu(SO(3))(4) yields a mixed oxidation state, 2D network of composition Na(5){[Cu(II)(H(2)O)][Cu(I)(SO(3))(4)]}·6H(2)O. The addition of Cu(II) and 2,2'-bipyridine to an aqueous Na(7)Cu(SO(3))(4) solution leads to the formation of a pentanuclear complex of composition {[Cu(II)(H(2)O)(bipy)](4)[Cu(I)(SO(3))(4)]}(+); a combination of hydrogen bonding and π-π stacking interactions leads to the generation of infinite parallel channels that are occupied by disordered nitrate anions and water molecules. A pair of Cu(SO(3))(4)(7-) anions each act as a tridentate ligand towards a single Mn(II) centre when Mn(II) ions are combined with an excess of Cu(SO(3))(4)(7-). An anionic pentanuclear complex of composition {[Cu(I)(SO(3))(4)](2)[Fe(III)(H(2)O)](3)(O)} is formed when Fe(II) is added to a Cu(+)/SO(3)(2-) solution. Hydrated ferrous [Fe(H(2)O)(6)(2+)] and sodium ions act as counterions for the complexes and are responsible for the formation of an extensive hydrogen bond network within the crystal. Magnetic susceptibility studies over the temperature range 2-300 K show that weak ferromagnetic coupling occurs within the Cu(II) containing chains of Na(5){[Cu(II)(H(2)O)][Cu(I)(SO(3))(4)]}·6H(2)O, while zero coupling exists in the pentanuclear cluster {[Cu(II)(H(2)O)(bipy)](4)[Cu(I)(SO(3))(4)]}(NO(3))·H(2)O. Weak Mn(II)-O-S-O-Mn(II) antiferromagnetic coupling occurs in Na(H(2)O)(6){[Cu(I)(SO(3))(4)][Mn(II)(H(2)O)(2)](3)}, the latter formed when Mn was in excess during synthesis. The compound, Na(3)(H(2)O)(6)[Fe(II)(H(2)O)(6)](2){[Cu(I)(SO(3))(4)](2)[Fe(III)(H(2)O)](3)(O)}·H(2)O, contained trace magnetic impurities that affected the expected magnetic behaviour.

Dy2(SO3)2(SO4)(H2O)2: the first lanthanide mixed sulfate-sulfite inorganic compound

The first lanthanide mixed sulfate-sulfite inorganic coordination polymer, poly[diaqua-μ(4)-sulfato-di-μ(4)-sulfito-didysprosium(III)], [Dy(2)(SO(3))(2)(SO(4))(H(2)O)(2)](n), has been obtained, in which both sulfate and sulfite groups originate from the disproportionation of S(2)O(3)(2-) under hydrothermal and weakly acidic conditions. The crystal structure of the title compound exhibits a three-dimensional framework. The Dy(III) ion is surrounded by eight O atoms from one water molecule and two sulfate and five sulfite groups. These DyO(8) polyhedra have two shared edges and form an infinite zigzag Dy-O chain. In the bc plane, neighbouring chains are integrated through SO(3) trigonal pyramids, forming a two-dimensional sheet. Along the a-axial direction, the sulfate group, with the central S atom lying on a twofold axis, links adjacent two-dimensional sheets via two S-O-Dy connections, thus generating the three-dimensional framework.