Reversible binding of carbon monoxide with Ru(III) aminopolycarboxylic acid complexes

Abstract

The reversible binding of carbon monoxide to the complexes [Ru^III(EDTA-H)(H₂O)] <strong>1</strong> and [RU^III(PDTA-H)(H₂O)] <strong>2</strong> have been studied in aqueous solution at <em>p</em>H = 5 by spectrophotometric and electrochemical studies. The equilibrium constant for carbonylation, <em>K</em>_CO was evaluated at 10°, 25° and 40°C. The thermodynamic parameters, D<em>H</em>ᵒ<em>,</em> D<em>G</em>ᵒ and D<em>S</em>ᵒ for the carbonylation of the complexes <strong>1</strong> and <strong>2</strong> have been evaluated. The complex [Ru(PDTA-H)(CO)] <strong>4</strong> is more stable than the complex [Ru(EDTA-H)(CO)] <strong>3</strong> in solution.