Metal-ion interactions with carbohydrates. Crystal structure and FT-IR study of the SmCl3-ribose complex.
A single-crystal of SmCl3.C5H10O5.5H2O was obtained from methanol-water solution and its structure determined by X-ray. Two forms of the complex as a pair of anomers and related conformers were found in the single-crystal in a disordered state. One ligand is alpha-D-ribopyranose in the 4C1 conformation and the other one is beta-D-ribopyranose. The anomeric ratio is 1:1. Both ligands provide three hydroxyl groups in ax-eq-ax orientation for coordination. The Sm3+ ion is nine-coordinated with five Sm-O bonds from water molecules, three Sm-O bonds from hydroxyl groups of the D-ribopyranose and one Sm-Cl bond. The hydroxyl groups, water molecules and chloride ions form an extensive hydrogen-bond network. The IR spectral C-C, O-H, C-O, and C-O-H vibrations were observed to be shifted in the complex and the IR results are in accord with those of X-ray diffraction.
Lu
Yan
Y
Department of Chemical Engineering, Shanghai Institute of Technology, Shanghai 200235, China. luuyann@vip.sina.com
Guo
Jianyu
J
D002236:Carbohydrate Conformation; D002241:Carbohydrates / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D007477:Ions / Q000737:chemistry; D008670:Metals / Q000737:chemistry*; D015394:Molecular Structure; D012266:Ribose / Q000737:chemistry*; D012493:Samarium / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
D002241:Carbohydrates; D007477:Ions; D008670:Metals; D012493:Samarium; D012266:Ribose