(IUCr) Crystallography Journals Online

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Acta Cryst. (2007). E63, m1732-m1733 [ doi:10.1107/S1600536807024166 ]

Redetermination of trans-diaquatetramethanolcobalt(II) bis(rac-1,1'-binaphthalene-2,2'-diylphosphate) methanol disolvate monohydrate: a two-dimensional supramolecular hydrogen-bonded network

B. Wisser and C. Janiak

Abstract: In the title compound, trans-[Co(CH₃OH)₄(H₂O)₂](C₂₀H₁₂PO₄)₂·2CH₃OH·H₂O, the crystal packing shows a separation of the hydrophobic naphthyl ring systems from the hydrophilic part of the structure, viz. the (RO)₂PO₂^- phosphate anion, the cobalt complex cation and the solvent molecules. The binaphthyl tail-to-tail packing in the hydrophobic layer is governed by weak C-H [pi] interactions. The present study performed at 203 K confirms the previous room-temperature study [McCann, Murphy, Cardin & Convery (1991), Polyhedron, 10, 2771-2777], but with improved precision. The centrosymmetric cobalt complex has very similar Co-O bond lengths and is isostructural with the trans-[Cu(H₂O)₂(CH₃OH)₄]²⁺ cation (which features a tetragonally compressed instead of the typical Jahn-Teller distorted elongated copper octahedron) in the isotypic copper(II) compound. The high degree of similarity in the Co and Cu structures shows the dominating effect of the hydrogen-bonding network on the metal coordination polyhedra. All H atoms of the Co and Cu aqua and methanol ligands are engaged in typical strong hydrogen-bonding interactions.

Online 26 May 2007