Oxygen Exchange and Cleavage of the Glycinate Chelate [Co(H2NCH2CH2NH2)2(H2NCH2CO2)]2+ in Strongly Alkaline Solution

Abstract

Cleavage of the carboxylate chelate [Co(en)2(glyO)]2+ has been studied in 0.75 mol dm-3 NaOH . 18O-tracer results are interpreted as 16% C-O and 84% Co-O bond fission, the products ultimately being [Co(en)2(OH)2]+, CoII, and glyO -. The major Co-O cleavage path is interpreted as an SN1 (CB) process leading to both recapture of carboxylate oxygen (50%, kex = 4.8 × 10-6 s-1) and capture of solvent leading to [Co(en)2(OH)( glyO )]+ (50%).