Synthesis of (−)-hinokinin by oxidation of (−)-cubebin catalyzed by biomimetic metalloporphyrin catalytic systems

A catalytic system consisting of iron tetraphenylporphyrin supported on an alumina matrix for oxidation of (−)-cubebin with iodosylbenzene or hydrogen peroxide is reported. Conversion of (−)-cubebin is very efficient (100%) with 100% selectivity producing only (−)-hinokinin when iodosylbenzene is used as the oxidant and 70% conversion with 100% selectivity when hydrogen peroxide is the oxidant at room temperature under atmospheric pressure.