Reactivity of co-ordinated amino-acids. Part 1. Oxygen-18 exchange studies on the trans(fac)-bis(N-methyliminodiacetato)chromate(III) anion and N-methyliminodiacetic acid

Abstract

The rate of oxygen exchange of the trans(fac)-bis(N-methyliminodiacetato)chromate(III) anion and of N-methyliminodiacetic acid with solvent water varies with hydrogen-ion concentration. At 100 °C the latter reaction is 39 times faster than the former. A mechanism for ¹⁸O exchange of the co-ordinated ligand through acid-independent and acid-dependent paths is postulated. Both paths appear to involve one-ended dissociated species.