No abstract

Autoxidations of the pinanes, obtained after hydrogenation of naturally occurring Pinus elliottii oil, were performed with or without solvent, using the catalytic system Co(OAc)2/Mn(OAc)2/NH4Br in a 9:1:5 molar ratio, and dioxygen as the oxidant. The best selectivity for the pinanols was 71% (cis:trans ratio, 3:1) with 17% conversion. Autoxidations were also carried out in the absence of catalyst. The hydroperoxides formed with 17% conversion were decomposed with Na2SO3 and PPh3, resulting in 62% pinanols (cis:trans ratio, 5:1). The pyrolysis of the pinanols at 600 °C and a contact time of 1.15 × 10-2 s/mol yielded 54% of linalool. The side products were mainly due to an “ene” reaction, giving diastereoisomeric 1,2-dimethyl-3-isopropenylcyclopentanols. Keywords: Catalytic oxidation; pinane; pinanol; pyrolysis; linalool