Metal Complexes of Amino Acids. XI. Preparation and 13C NMR Spectra of the Cobalt(III) Complexes Containing β-Alanine and Glycine

Abstract

Abstract A series of complexes or geometrical isomers, [Co(β-ala or gly)(en)2]2+, [Co(β-ala or gly)2(en)]+, [Co(β-ala or gly)(ox)2]2−, and [Co(β-ala or gly)2(ox)]−, were prepared and their 13C NMR spectra were measured. Assignments of their structures and 13C NMR signals were made. The β-alaninate carbons in the complexes resonate at 33.6±0.5, 38.3±0.6, and 183.0±1.5 ppm and the glycinate carbons at 46.3±1.3 and 187.4±1.4 ppm. The 13C chemical shifts of the mixed (β-alaninato)(glycinato) complexes consist of those of the corresponding isomers of bis(β-alaninato) and bis(glycinato) complexes.