Reactions of complex compounds of cobalt. Part 10. Mixed complexes of cobalt(III) containing 3-azapentane-1,5-diamine and an amino-acid

Abstract

Several new complexes of 3-azapentane-1,5-diamine (apd) are described: [Co(apd)(GlyO)(OH₂)]²⁺, [Co(apd)(Gly)(OH₂)]³⁺(Gly = glycine, GlyO = glycinate) with a protonated co-ordinated carboxyl group, and [Co(apd)(PheO)(OH)]⁺(PheO = phenylalaninate). These are unexpectedly obtained as the major products from the reaction at low temperature of [Co(apd)(OH)₃] with glycylglycylglycine or L-phenylalanylglycylglycine. The ion [Co(apd)(C₂O₄)(OH₂)]⁺ has also been prepared for comparison, and the acidity constants for these and for several other aqua(3-azapentane-1,5-diamine)cobalt(III) complexes are given.