Microencapsulated methylrhenium trioxide (MTO)/H2O2 systems for the oxidation of cardanol derivatives

Saladino, R.; Mincione, E.; Attanasi, O. A.; Filippone, Paolino

doi:10.1351/pac200375020265

Pure Appl. Chem., 2003, Vol. 75, No. 2-3, pp. 265-272

http://dx.doi.org/10.1351/pac200375020265

Microencapsulated methylrhenium trioxide (MTO)/H2O2 systems for the oxidation of cardanol derivatives

R. Saladino^1,2*, E. Mincione¹, O. A. Attanasi³ and Paolino Filippone³

¹ Dipartimento di Agrobiologia ed Agrochimica, Unità INFM, Università della Tuscia, Via S. Camillo de Lellis, 01100 Viterbo, Italy
² Unità INFM, Università della Tuscia, Via S. Camillo de Lellis, 01100 Viterbo, Italy
³ Centro di Studio delle Sostanze Naturali, Università di Urbino, 61029 Urbino, Italy

Abstract: A convenient and efficient application of microencapsulated/methylrhenium trioxide (MTO) and MTO/pyridine systems for the selective oxidation of cardanol derivatives is reported. Environmentally friendly and low-cost H₂O₂ was used as the oxygen atom donor. The catalysts were stable systems for at least five recycling experiments. In the oxidation of C2 alkyl-substituted cardanol derivatives, high conversion and yields of the corresponding para-benzoquinones were obtained. By contrast, in the absence of the C2 substituent, an unprecedented oxidative degradation to di-γ-lactone derivative was observed.