Alumina-supported vanadyl complexes as catalysts for the Csingle bondH bond activation of cyclohexene with tert-butylhydroperoxide

Abstract

Alumina-supported vanadyl complexes with ligands of ethylenediamine (en); [VO(en)2]SO4-Al2O32-alum; tetramethylethylenediamine (TMED); [VO(TMED)2]SO4-Al2O33-alum; bipyridine (bpy); [VO(bpy)2]SO4-Al2O34-alum; 1,10-phenantroline (phen); [VO(phen)2]SO4- Al2O35-alum; acetylacetonato (acac); [VO(acac)2]-Al2O3; 6-alum; N,N-ethylenebis(salicylideneiminato) (salen); [VO(salen)]-Al2O37- alum; N,N-phenylenebis(salicylideneiminato) (salophen); [VO(salophen)]-Al2O38-alum; catalyzed the oxidation of cyclohexene with tertbutylhydroperoxide (TBHP). The major products of the reaction were 2-cyclohexene-1-one. The influence of solvent and time for the oxidation reaction has been studied. The selectivity of the 2-cyclohexene-1-(tert-butylperoxy) varied with reaction time. Alumina-supported vanadyl catalysts with the nitrogen donor ligands show significantly higher catalytic activity than oxygen donor ligands at the same surface coverage. [VO(bpy)2](SO4)-Al2O3 shows significantly higher catalytic activity than other alumina supported vanandyl complexes. These catalysts can also be reused in the oxidation of cyclohexene for several times.