Binding of p-aminobenzoate anion to bis(diethylenetriamine)cobalt(III) cation in solution and solid phases: synthesis, characterization, and X-ray structure determination of s-fac-[Co(dien)(2)]Cl(p-aminobenzoate)(2)center dot 3H(2)O

作者：Bala Ritu^*; Kaur Amrinder; Kashyap Monika; Golobic Amalija

来源：Monatshefte fur Chemie, 2014, 145(6): 937-944.

DOI：10.1007/s00706-014-1170-4

• Anion binding agent
• Cobalt(III)
• Coordination chemistry
• Synthesis
• UV-Vis titrations
• X-ray crystallography

The reaction of an isomeric mixture of [Co(dien)(2)]Cl-3 with sodium salt of p-aminobenzoic acid in aqueous medium leads to the formation of dark orange coloured crystals of composition s-fac-[Co(dien)(2)]Cl(p-aminobenzoate)(2)center dot 3H(2)O. The configuration of the cationic isomer was initially determined with the help of spectroscopic data (NMR, UV-Vis, and IR). The binding properties of s-fac-bis(diethylenetriamine)cobalt(III) cation with p-aminobenzoate anion has been determined (in solution phase) with the help of UV-Vis spectroscopic titrations. Single crystal X-ray structure determination of title complex reveals the presence of one cation, three anions (one Cl and two p-aminobenzoates) along with three lattice water molecules. The crystal lattice is stabilized by electrostatic forces of attraction and H-bond interactions (N-H center dot center dot center dot O, N-H center dot center dot center dot Cl, O-H center dot center dot center dot O, and O-H center dot center dot center dot Cl). The water molecules of crystallization play a major role in stabilizing the complex by forming intermolecular H-bonds with Cl- and O atoms of p-aminobenzoate and water.

• 出版日期2014-6