Heterogeneous catalysis in the liquid phase oxidation of alcohols by Cu(II) complexes immobilized between silicate layers of bentonite

Immobilized Cu(II) complexes with ligands of 2,2'-bipyridine (bpy), ethylenediamine (en), N, N'-ethylenebis (salycili-deneamine) (salen) and acetylacetonate (acac), were used for oxidation of alcohols such as cyclohexanol, hexanol, benzyl alcohol and trans-2-hexene-1-ol with tert-butylhydroperoxide (TBHP) as oxidant. The high conversion percentage of cyclohexanol about 98% with 100% selectivity toward the formation of cyclohexanone with [Cu(bpy)(2)](+2)/bentonite is remarkable. (C) 2002 Elsevier Science B.V. All rights reserved.