alpha-Terpineol from hydration of crude sulfate turpentine oil.
ABSTRACT Hydration of alpha-pinene under various conditions was studied and compared with the literature. Optimal reaction conditions have been established for the hydration of alpha-pinene and crude turpentine oil in the absence of catalyst and using a low volume of acetone. A detailed reaction product analysis is reported. The main hydration product, alpha-terpineol, was obtained at a yield of 67 wt % of the initial alpha-pinene by reacting with 15% aqueous sulfuric acid and an excess of acetone in an oil bath heated to 80-85 degrees C over the course of 4 h. A progressive transformation of alpha-terpineol to 4-(2-hydroxypropyl)-1-methylcyclohexanol (1,8-terpine) takes place as the hydration time exceeds 4 h. A crude turpentine oil sample was also hydrated under conditions similar to those of alpha-pinene. The alpha-terpineol yield was 77 wt % of the initial alpha-pinene in the crude turpentine oil. The chemical analysis of the crude turpentine oil before and after hydration was carried out, and the distribution of the products was discussed.
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ABSTRACT: Monoterpenes in exudates, phloem, and sapwood have received considerable attention relative to the active defenses of pine trees. However, little is known about the composition and function of the heartwood monoterpenes. To address this deficiency, monoterpene contents and relative compositions were determined for sapwood and heartwood samples from longleaf pine (Pinus palustris Mill.) stumps monitored in the field for a 1 year period postharvest. Gas chromatography - mass spectrometry analysis of sapwood and heartwood sample extracts showed the total monoterpene contents for both declined at essentially the same rate. For sapwood, α-pinene continued to comprise about 75% of all compounds detected, while the proportion of β-pinene declined with time (15%-7%). For the heartwood, lower proportions of both α- and β-pinenes (64% and 10%, respectively) were offset by higher proportions of other monoterpenes (e.g., limonene, α-terpineol, borneol). The low proportion of β-pinene in very old turpentine and lightwood stump samples further suggested the lower stability of this particular monoterpene. While it has not been specifically demonstrated that the monoterpenes have an active role in the decay resistance of longleaf pine stump heartwood, these compounds do persist for a very long time and thus are available should they serve this function.Canadian Journal of Forest Research 07/2009; 39(7). DOI:10.1139/X09-063 · 1.66 Impact Factor
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ABSTRACT: Differences in the compositions of volatiles from dried omija fruits (Schisandra chinensis Baillon) cultivated in different areas (Mungyeong, Jangsu, Jechon, and Hoengseong) in South Korea were determined by applying principal component analysis to gas chromatography-mass spectrometry data sets. Quantitative assessments revealed that terpene hydrocarbons, such as germacrene D, β-selinene, α-ylangene, β-elemene, α-selinene, and (E)-β-farnesene, were the main volatiles in all omija fruit samples. On the other hand, (E)-β-ocimene, calarene, (E)-β-farnesene, β-selinene, nonanal, 2-methylbutanoic acid, benzoic acid, 2,3-butanediol, and phenethyl alcohol were the major volatile components that contributed to the discrimination between omija fruit samples from the four cultivation areas. In addition, aroma-active compounds in four dried omija fruits were investigated and compared by gas chromatography-olfactometry using aroma extract dilution analysis. (E)-β-Ocimene (floral and herbaceous), α-pinene (pine-like and woody), hexanal (cut grass-like), 5-methylfurfural (burnt sugar-like and sweet), and α-terpinene (minty, green, and fresh) were important aroma-active compounds in all omija samples. Interestingly, the flavor dilution factors of most aroma-active compounds were lower for omija sample cultivated in Hoengseong than for those cultivated in Mungyeong, Jangsu, and Jechon.Journal of Agricultural and Food Chemistry 06/2011; 59(15):8338-46. DOI:10.1021/jf200762h · 3.11 Impact Factor
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ABSTRACT: A study of turpentine direct hydration was carried out, using macropore and strong acidic cation exchange resin Amberlyst 15 wet as catalyst. During the hydration process, the isomerization of α-pinene also took place under the catalytic condition. The effects of different parameters such as agitation speed, catalyst type, catalyst loading, mass ratio of the reactants, temperature and the reusability of catalyst on the conversion of turpentine and the yield of α-terpineol were investigated to obtain the optimal reaction conditions in a stirred-tank reactor. Based on these optimized conditions, the experiment was conducted in a new pilot-scale jet reactor to achieve an excellent performance. Kinetics of the direct hydration reaction was also performed in the temperature range 328.15–348.15 K. A pseudohomogeneous (PH) model was used to explain the reaction rate equation and to determine the reaction rate constants and reaction activation energy.Chemical Engineering Journal 03/2011; 168(1):351-358. DOI:10.1016/j.cej.2011.01.037 · 4.06 Impact Factor