Tris(β-diketonato)chromium(III) complexes: Effect of the β-diketonate ligand on the redox properties

A combined quantum chemistry and electrochemistry study of a series of tris(beta-diketonato)-Cr(III) complexes showed that the different electron donating properties of the R and R' groups, substituted on the 1 and 3 positions of the beta-diketonate ligand (RCOCHCOR'), largely influence the redox properties of these complexes, due to the good communication between the R and R' groups and the metal via the beta-diketonato-metal conjugated system. Linear relationships were obtained between the reduction potential of the tris(beta-diketonato)-Cr(III) complexes and a variety of electronic parameters used to describe the electron-donating and -withdrawing power of the R and R' groups on the beta-diketonate ligand. (C) 2015 Elsevier Ltd. All rights reserved.