Oxidation of cyclohexene with tert-butylhydroperoxide and hydrogen peroxide catalysted by Cu(II), Ni(II), Co(II) and Mn(II) complexes of N,N′-bis-(α-methylsalicylidene)-2,2-dimethylpropane-1,3-diamine, supported on alumina

New square-planar manganese(II), copper(II), nickel(II) and cobalt(II) complexes of a tetradentate Schiff-base ligand “N,N′-bis-(α-methylsalicylidene)-2,2-dimethylpropane-1,3-diamine, H2[Me2salpnMe2]” have been prepared and characterized by elemental analyses, IR, UV-vIS, conductometric and magnetic measurements. The results suggest that the symmetrical Schiff-base is a bivalent anion with tetradentate ONNO donors derived from the phenolic oxygen and azomethine nitrogen. The formulae was found to be [M(Me2salpnMe2)] for the 1:1 non-electrolytic complexes. Alumina-supported metal complexes (ASMC); [M(Me2salpnMe2]/Al2O3; catalyze the oxidation of cyclohexene with tert-buthylhydroperoxide (TBHP) and hydrogen peroxide. Manganese(II) complex supported on alumina “[Mn(Me2salpnMe2]/Al2O3” shows significantly higher catalytic activity than other catalysts.