Journal of Molecular Catalysis A-Chemical, Vol.176, No.1-2, 23-27, 2001
Palladium-catalyzed oxidation of monoterpenes: novel tandem oxidative coupling-oxidation of camphene by dioxygen
The Pd-catalyzed stereoselective oxidative coupling of (-)-camphene gives mainly (E,E)-diene, i.e., bis(3,3-dimethyl-2-norbornylidene)ethane, which can be oxidized into the corresponding alpha,beta -unsaturated ketone, i.e. (3,3-dimethyl-2-norbornyl) (8-camphenyl)ketone, with LiNO3 being used as a reoxidant and dioxygen as a final oxidant; these two reactions are performed in a one port process with up to 90% selectivity for ketone. The applications of the Pd(II)/NO3- catalytic system to the oxidation of limonene and beta -pinene have also been studied.