Synthesis of new Co(III) hetero-ligand complexes with imidazole and 1-methylimidazole and their H-1, C-13 and Co-59 NMR spectra

cis-[Co(en)(2)(1-MeIm)(2)]Cl-3, fac-[Co(dien)(ImH)(3)]X-3 (X = Cl-, NO3-, C lO4-) and fac-[Co(dien)(1-MeIm)(3)]Cl-3 complexes were prepared and charact erized by absorption, H-1 NMR, C-13 NMR and Co-59 NMR spectra, where en, di en, ImH and 1-MeIm denote ethylenediamine, diethylenetriamine, imidazole an d 1-methylimidazole, respectively. Calculated coordination-induced shifts ( delta(complexed) - delta(free)) ranged from +0.62 to -0.03 ppm for H-1 and +7.11 to -1.19 ppm for C-13 nuclei of imidazole ligands. The influence of i midazole methylation on Co-59 NMR spectra was considered.