The Molecular and Crystal Structures of 2-Iodokojic Acid: Experimental and Theoretical Determination

The crystal structure of 2-iodokojic acid, (2-jodo-3-hydroxy-6-hydroxymethyl)-4-H-pyran-4-one) (C6H5IO4, Mr = 268.00) has been determined by single crystal X-ray diffraction analysis. The compound crystallizes in the orthorhombic crystal system with space group Pc2(1)b and unit cell parameters: a = 4.0830(2), b = 15.3510(5), c = 23.517(1) and Z = 8. The final reliability index is 0.0288 for 2,584 observed reflections. The two molecules of iodokojic acid, slightly differing in their molecular structure, are localized in independent part of unit cell. The crystal packing is stabilized by O-H center dot center dot center dot O hydrogen bonds and I center dot center dot center dot O intermolecular interactions. The molecular structure of iodokojic acid determined experimentally little differs from that obtained by the applied theoretical (Hartree-Fock and four versions of DFT) methods, the differences should not be taken as a measure of the reliability of the theoretical methods.