Dergiler / Turkish Journal of Chemistry / 2004 / Cilt: 28 - Sayı: 6
An Atropisomeric Chiral 2,2'-bipyridyl-3,3'-dicarboxylic Acid and Corresponding Platinum(II) Complex
- Sayfa
- 703–714
- DOI
- —
Özet
2,2'-Bipyridyl-3,3'-dicarboxylic acid (H2BDC) spontaneously resolves on crystallization from water, giving monohydrated crystals of the space group P212121. In any individual crystal, all the atropisomeric-skewed molecules are of one hand; however, on dissolution in water, optical activity is lost. Strong hydrogen bonding leads to a helical structure, via O--H ... N links, and 3 further strong bonds between water and carboxylate groups produce a framework structure. The pKa values measured for H2BDC (3.18 \pm 0.04 and 4.59 \pm 0.02 at 20 \pm 1 °C, in dilute aqueous solution) agree with the zwitterionic form. The reaction of H2BDC with potassium tetrachloroplatinate(II) in water gives Pt(H2BDC)Cl2 . H2O. The complex was characterized by elemental analysis and spectroscopic techniques.
Abstract
2,2'-Bipyridyl-3,3'-dicarboxylic acid (H2BDC) spontaneously resolves on crystallization from water, giving monohydrated crystals of the space group P212121. In any individual crystal, all the atropisomeric-skewed molecules are of one hand; however, on dissolution in water, optical activity is lost. Strong hydrogen bonding leads to a helical structure, via O--H ... N links, and 3 further strong bonds between water and carboxylate groups produce a framework structure. The pKa values measured for H2BDC (3.18 \pm 0.04 and 4.59 \pm 0.02 at 20 \pm 1 °C, in dilute aqueous solution) agree with the zwitterionic form. The reaction of H2BDC with potassium tetrachloroplatinate(II) in water gives Pt(H2BDC)Cl2 . H2O. The complex was characterized by elemental analysis and spectroscopic techniques.