CW electron paramagnetic resonance (EPR) investigation using the X-band, performed at the reaction temperature (298 K) showed that two phenoxy cobalt radicals ([CoIII(salen)(ROH)(RO˙)] and [CoIII(salen)(RO−)(RO˙)]) are involved in the oxidation mechanism of all the phenol compounds ROH. In a frozen solution the [CoIII(salen)(ROH))(RO˙)] radical prevailed and its axial magnetic anisotropy was determined
Crude peroxidase from onion solid waste as a tool for organic synthesis. Part II: oxidative dimerization–cyclization of methyl p-coumarate, methyl caffeate and methyl ferulate
The ability of a crude onion peroxidase preparation to act as a biocatalyst for the oxidative dimerization–cyclization of methyl p-coumarate, methyl caffeate and methyl ferulate is presented. The products of the reaction have been fully characterized and were found to possess potent antioxidant activity in a ferric reducing antioxidant power (FRAP) assay.