Synthesis, characterization and cis-trans influence in cobaloximes with nioxime

A synthetic scheme leading to the (X)(Y)bis(1,2-cyclohexanedionedioximato)c obalt(III) complexes, where X = Cl, N-3, CICH2, CH3, C2H5 and Y = PPh3 and Py is reported. The complexes have been characterized by the usual spectros copic techniques and have been compared with the reported analogous compoun ds having other dioximes as the equatorial ligands. The first crystal struc ture of an inorganic cobaloxime with 1,2-cyclohexanedionedioxime (Nioxime) is reported. For a range of X ligands, a clear trend between P-31, C-13, H- 1 chemical shifts of the equatorial and axial ligands as well as with the C o --> chgH charge transfer band has been observed. (C) 2000 Elsevier Scienc e S.A. All rights reserved.