Synthesis, characterisation and crystal structure of 1,2-bis(6-methylpyridin-2-yl)ethene-1,2-diol

From the condensation reaction of (6-methylpyridin-2-yl)methanol and pyridine-2-carbaidehyde at 130 degrees C without catalyst or solvent was isolated an unexpected compound 1,2-bis(6-methylpyridin-2-yl)ethene-1,2-diol, in crystal form. The new compound was characterised by mass spectroscopy, IR, H-1 NMR, UV-Vis and single crystal X-ray diffraction showing that it is a symmetrical molecule with two intramolecular hydrogen bonds. The molecular and crystalline structure of 1,2-bis(6-methylpyridin-2-yl)ethene-1,2-diol indicated that the molecule crystallised in a monoclinic crystal system and belongs to P2(1)/c space group with two molecules per unit cell. Within the accuracy of the analysis the molecule is planar and there are two moderate intramolecular O-(HN)-N-... hydrogen bonds. We think that the presence of two moderate intramolecular hydrogen bonds gives stabilisation to the crystal structure, making isolation of a single crystal form possible.