Synthesis, characterization and investigation of homogeneous oxidation activities of peripherally tetra-substituted Co(II) and Fe(II) phthalocyanines: Oxidation of cyclohexene

The synthesis and characterization of novel peripherally tetra-substituted iron(II) 4 and cobalt(II) 5 phthalocyanines are described for the first time in this study. All the new compounds are characterized by a combination of IR, H-1 and C-13 NMR, mass and UV-vis spectroscopy techniques. Complexes 4 and 5 served as catalyst for the oxidation of cyclohexene using different types of oxidants, such as tert-butyl hydroperoxide (TBHP), m-chloroperoxybenzoic acid (m-CPBA), aerobic oxygen and hydrogen peroxide (H2O2). During the oxidation process the products formed are 2-cyclohexene-1-ol, 2-cyclohexene-1-one and cyclohexene oxide. The selectivity for 2-cyclohexene-1-ol is favored when iron(II) and cobalt(II) phthalocyanine catalysts are employed. The higher conversion is obtained as catalyst iron(II) phthalocyanine (96%). TBHP was determined as the successful oxidant with the minimum demolition of the catalyst, superior selectivity and conversion in the oxidation products. (c) 2013 Elsevier B.V. All rights reserved.