The chemistry of vitamin B12. Part 26. Co-ordination of the malonitrile anion by CoIII corrinoids: first experimental determination of equilibrium constants for the co-ordination of a tetrahedral carbanion by a transition–metal ion
Abstract
Equilibrium constants for the substitution of co-ordinated H2O by the malonitrile anion, CH(CN)2–, in the CoIII corrinoids aquocobalamin and diaquocobinamide have been determined in aqueous solution at 25 °C as log K(dm3 mol–1)= 7.4 and ca. 11.5 respectively.