Structures of transition and alkaline earth metal salts of 5-aminonaphthalene-2-sulfonate and 6-aminonaphthalene-1, 3-disulfonate: Some unusual coordination behaviors

Salts of 5-aminonaphthalene-2-sulfonate with divalent Mg, Mn, Co, and Ni cations have been crystallized and their structures determined by single crystal X-ray methods. The Mg, Mn, and Co salts are isostructural. Crystal data for hexaaquamagnesium(II) 5-aminonaphthalene-2-sulfonate hexahydrate, [Mg(H2O)6](H2NC10H6SO3)2·6H2O: monoclinic, P21/c, Z=2, a=14.1329(18) Å, b=8.5789(11) Å, c=12.4880(17) Å, β=93.374(3)°, V=1511.5(3) Å3; hexaaquamanganese(II) 5-aminonaphthalene-2-sulfonate hexahydrate, [Mn(H2O)6](H2NC10H6SO3)2·6H2O: monoclinic, P21/c, Z=2, a=14.249(3) Å, b=8.5940(17) Å, c=12.505(3) Å, β=93.30(3)°, V=1528.8(6) Å3; hexaaquacobalt(II) 5-aminonaphthalene-2-sulfonate hexahydrate, [Co(H2O)6](H2NC10H6SO3)2·6H2O: monoclinic, P21/c, Z=2, a=14.1406(18) Å, b=8.5674(11) Å, c=12.4960(16) Å, β=93.297(2)°, V=1511.4(3) Å3. The structures are composed of alternating layers of octahedral metal–aqua complexes and sulfonate anions linked by hydrogen bonds. The three water molecules of crystallization are associated with the hexaaquametal cations and sulfonate O atoms. The repeat unit along the a-axis is a single layer. The Ni salt [crystal data for tetraaquabis(5-aminonaphthalene-2-sulfonato-N)nickel(II) dihydrate, [Ni(H2O)4(H2NC10H6SO3)2]·2H2O: triclinic, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$P\bar 1$$\end{document}, Z=1, a=6.8524(10) Å, b=8.3094(12) Å, c=11.4832(17) Å, α=69.003(2)°, β=76.570(3)°, γ=83.952(2)°, V=593.56(15) Å3] has a very different structure with direct coordination of the amine N atom to Ni, a modified stacking pattern, and fewer free water molecules. Ag and Ni salts of an amine-substituted naphthalenedisulfonate have also been characterized. Crystal data for diaqua(6-ammonionaphthalene-1,3-disulfonato-O)silver(I) hydrate,