Kinetic peculiarities of α-pinene oxidation by molecular oxygen

Kinetic study of α-pinene allylic oxidation over FePcCl16-NH2-SiO2 catalyst

“…In other study, a proposed mechanism for α-pinene liquid-phase oxidation by O2over Pd/C catalyst (343-393 K and 0.5-6 bar O2 pressure) involves two consecutive steps: (i) α-pinene oxidation by O2 to verbenyl hydroperoxide (VHP) intermediate and α-pinene epoxide and (ii) selective reduction of VHP to verbenol by H2 over the catalyst [27]. The mechanism was proposed as a set of radical chain steps.…”

“…The mechanism was proposed as a set of radical chain steps. The authors suggested for the step (i) a kinetic equation of first order regarding to the O2 pressure and half order respect to VHP concentration [27]. Until now, there are no reports about the kinetic of the α-pinene allylic oxidation to verbenone considering both the radicalary mechanism and the heterogeneous catalytic process.…”

Vanadium-containing nickel phosphate molecular sieves as catalysts for α-pinene oxidation with molecular oxygen: A study of the effect of vanadium content on activity and selectivity

“…Thus, rearrangement of ␣-pinene epoxide into ␣-campholenic aldehyde over Lewis acid sites of Ti-and Co-containing materials was demonstrated [28,29]. In the presence of Brönsted acids ␣-pinene epoxide rearrange into trans-carveol [27,28]. Because of this reason, the relationships between the nature of the surface functional groups, the vanadium state and catalytic activity of V-VSB-5 materials were investigated.…”

“…Therefore, the development of catalytic methods for the selective oxidation of ␣-pinene over heterogeneous catalysts is a challenging goal of fine chemistry. Recently, the oxidation of ␣-pinene with molecular oxygen was demonstrated in the present of various catalytic systems, such as cobalt-containing systems [19][20][21], gold catalysts [22], uranyl-containing MCM-41 [23], manganese-containing systems [24][25][26], Ru-and Pd-containing materials [18,27]. It is well-known that ␣-pinene oxidation with molecular oxygen proceeds via a free radical chain mechanism with formation of verbenol and verbenone (the allylic oxidation products).…”

Evaluation of Fe- and Cr-containing clinoptilolite catalysts for the production of camphene from α-pinene

“…A large number of scientific publications about the transformation of biomass into valuable chemicals have appeared in the last years [1,2]. a-Pinene, a terpene extracted from biomass, is an inexpensive raw materials that is widely used in the synthesis of fine chemicals [3][4][5]. aPinene is the most abundant member of a large class of terpene hydrocarbons and it rearranges readily in the presence of an acid catalyst to yield several isomeric products through two parallel routes.…”