New dioxygen-inert triphenylantimony(v) catecholate complexes based on o-quinones with electron-withdrawing groups

摘要

New triphenylantimony(v) catecholate complexes were synthesized by oxidative addition of sterically hindered o-benzoquinones containing electron-withdrawing substituents in different positions of the carbon ring to triphenylantimony. The complexes were characterized using IR spectroscopy, NMR spectroscopy, and cyclic voltammetry. The oxygen-inertness of the complexes is shown by NMR spectroscopy and electrochemical studies. The introduction of electron-withdrawing substituents to the catecholate ligand shifts the first oxidation potential of the complexes to the electropositive region and thus deactivates the triphenylantimony(v) catecholate complexes in the reaction with molecular oxygen.