Interesting Green Catalysis of Cyclohexane Oxidation over Metal Tetrakis(4-carboxyphenyl)porphyrins Promoted by Zinc Sulfide

To mimic the activity regulated by a cysteinate axial ligand in cytochrome P450 enzymes, metal tetrakis(4-carboxyphenyl)porphyrins (M TCPP) were immobilized on ZnS. They were characterized by a variety of spectroscopic techniques and were used as a catalyst for cyclohexane oxidation. The small amount of metal (Co, Fe, or Mn) TCPP (1.1 mu mol) in the immobilized catalyst could be reused three times for oxidation, providing more than 6.5 X 10(5) turnover number and 20% molar yield of cyclohexanone and cyclohexanol (KA oil) on average. The coordination of ZnS played a key role. These catalysts were applied to green catalytic oxidation of cyclohexane to produce KA oil products.