The oxidation of carvacrol 1, thymol 2 and p-cymene 3 with hydrogen peroxid
e catalysed by Mn(III) porphyrins is reported. The oxidation of 1 and 2 sel
ectively originates thymoquinone 6. From the oxidation of p-cymene 3, the i
solated major products 7-10, were formed from the oxidation of positions 7
and 8 of the substrate, although minor amounts of thymoquinone 6 were also
formed. The efficiency and selectivity of the catalytic systems and the str
uctural characterisation of the products obtained will be discussed. (C) 19
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