71697-84-2Relevant articles and documents
Chemo-enzymatic pathways toward pinene-based renewable materials
Stamm,Tengdelius,Schmidt,Engstr?m,Syrén,Fogelstr?m,Malmstr?m
, p. 2720 - 2731 (2019)
Sobrerol methacrylate (SobMA) was synthesized and subsequently polymerized using different chemical and enzymatic routes. Sobrerol was enzymatically converted from α-pinene in a small model scale by a Cytochrome P450 mutant from Bacillus megaterium. Conve
Hot water-promoted SN1 solvolysis reactions of allylic and benzylic alcohols
Xu, Zhao-Bing,Qu, Jin
supporting information, p. 314 - 323 (2013/03/13)
During the studies of hydrolysis of epoxides in water, we found that the hydrolysis of (-)-α-pinene oxide at 20 °C gave enantiomerically pure trans-(-)-sobrerol, whereas the same reaction in water heated at reflux unexpectedly gave a racemic mixture of trans- and cis-sobrerol (trans/cis=6:4). We have examined this remarkable difference in detail and found that hot water, whose behavior is quite different compared with room- or high-temperature water, could promote SN1 solvolysis reactions of allylic alcohols and thus caused the racemization of trans-(-)-sobrerol. The effect of reaction temperature, the addition of organic co-solvent, and the concentration of the solute on the rate of the racemization of trans-(-)-sobrerol were further examined to understand the role that hot water played in the reaction. It was proposed that the catalytic effects of hot water are owing to its mild acidic characteristic, thermal activation, high ionizing power, and better solubility of organic reactant. Further investigation showed that the racemization of other chiral allylic/benzylic alcohols could efficiently proceed in hot water.
Isomerization of α-pinene oxide over cerium and tin catalysts: Selective synthesis of trans-carveol and trans-sobrerol
Costa, Vinícius V.,Da Silva Rocha, Kelly A.,De Sousa, Líniker F.,Robles-Dutenhefner, Patricia A.,Gusevskaya, Elena V.
experimental part, p. 69 - 74 (2011/10/05)
A remarkable effect of the solvent nature on the acid catalyzed transformation of α-pinene oxide allowed direction of the reaction to either trans-carveol or trans-sobrerol. Each of these highly valuable compounds was obtained in nearly 70% yield using an appropriate polar solvent, whose basicity affected strongly the product distribution. In acetone, a weakly basic solvent, the reaction over heterogeneous sol-gel Sn/SiO2 or Ce/SiO2 catalysts gave mainly trans-sobrerol. No leaching of active components occurs under the reaction conditions and the catalysts can be recovered and reused. On the other hand, in more basic solvent, i.e., dimethylacetamide, the reaction was essentially directed to trans-carveol. Due to the leaching problems with Sn/SiO2 and Ce/SiO2 materials, the synthesis of trans-carveol was performed under homogeneous conditions using CeCl3 or SnCl2 as catalysts with a catalyst turnover number up to ca. 1200. The method represents one of the few examples of the synthesis of isomers from α-pinene oxide, other than campholenic aldehyde, with a sufficient for practical usage selectivity.
