The Synthesis of Copper(II) Salicylaldiminato Complexes and their Catalytic Activity in the Hydroxylation of Phenol
Artikel i vetenskaplig tidskrift, 2007
The synthesis of copper(II) salicylaldiminato complexes and their application in the catalytic hydroxylation
of phenol is reported. Tetracoordinated copper complexes (Cu(Ln)2) were obtained by reacting
the N-phenylsalicylaldimine ligands (HL1 –HL7) with copper acetate in a 2 : 1 mole ratio. The
reaction of N-(2,6-diisopropyl)phenyl-3,5-di-tert-butylsalicylaldimine (HL7) with copper acetate in a
1 : 1 mole ratio afforded a dinuclear complex, which was not obtained with the other ligand systems.
All complexes were characterized using FT-IR and elemental analysis. X-Ray crystal structures of
complexes 2, 5 and 8 have also been obtained. The catalytic activity of these complexes was evaluated
in the hydroxylation of phenol using oxygen and hydrogen peroxide as co-oxidants in aqueous
media in the pH range 3 – 6. All complexes studied were found to be active for the hydroxylation
process over the pH range studied with higher selectivity for catechol formation.
Tetracoordinated Copper(II) Complexes