Crystal structure of a hydrated complex of sodium iodide with phenacylkojate [2-(hydroxymethyl)-5-phenacyl-4H-pyran-4-one]

Abstract

The structure of the title complex has been determined by three-dimensional X-ray crystal-structure analysis. Crystals are orthorhombic, space group P2₁2₁2₁, with unit-cell dimensions a= 12·215(7), b= 33·424(11), and c= 7·004 Å, Z= 4. The structure was solved by the heavy-atom method and refined by full-matrix least-squares to R 0·067 for 843 independent diffractometer observations. The two independent molecules of phenacylkojate have different environments, one co-ordinating to the sodium ion and the other hydrogen bonding to a water molecule. The environment about the sodium ion is approximately octahedral with Na⁺–O distances in the range 2·30–2·58 Å; three equatorial positions are occupied by oxygen atoms from one molecule, one apex by the hydroxy-group from another, and the two remaining (cis) positions by water molecules. Extensive hydrogen bonding between the hydroxy-groups, water molecules, and the iodide ion as well as the Na⁺–O co-ordination hold the polymeric structure together. Hydrogen-bond distances are in the range 2·76–2·85 for O ⋯ O and 3·48–3·55 Å for O ⋯ I^– contacts.