Dysprosium-doped zinc tungstate nanospheres as highly efficient heterogeneous catalysts in green oxidation of terpenic alcohols with hydrogen peroxide

A green route to oxidize terpenic alcohols (nerol and geraniol) with H2O2 over a solid catalyst was developed. The Dy-doped ZnWO4 catalyst was synthesized by coprecipitation and microwave-assisted hydrothermal heating,...

New adducts of turpentine and rosin with citraconic anhydride and itaconic acid

The reaction of pine gum rosin, turpentine and its components (α-pinene, ∆3-carene, α-terpinene) with citraconic anhydride and itaconic acid was investigated. It was shown that α-terpinene, in contrast to α-pinene and ∆3-carene, reacts with citraconic anhydride to give the unknown cycloaddition reaction product. Its structure was studied by the 2D NMR spectroscopy. Turpentine reacts with itaconic acid forming a complex mixture that contains esters of terpenic alcohols and itaconic acid. Reaction of rosin with citraconic anhydride was studied at 140–180 °С within 0.5–8 hrs in presence of catalytic amounts of H2SO4, MgCl2, AlCl3, FeCl3and new citraconopimaric adducts containing up to ~70 % of citraconopimaric acid as a mixture of two С15–CH3and С16–CH3isomers in equimolar ratio. The highest content of С15–CH3isomer of citraconopimaric acid (35.5–36.0 %) in the adducts was reached within 4–8 hrs at 180 °С in presence of 1–2 mass. % H2SO4. The reaction of rosin with citraconic anhydride at 140–160 °С leads to the formation of adduct containing up to 30–50 % of citraconopimaric acid isomers. The synthesized adducts may be used for production of composite materials for different applications (adhesives, polymer composite additives including rubber blends for tire production, components of grease-cooling liquids).

Chemical characterization of commercial and single-variety avocado oils

This work aimed to determine the major and minor compounds of avocado oils. Mono-varietal oils from the Bacon, Fuerte, Hass, and Pinkerton cultivars were obtained by means of an Abencor® system, while commercial oils from Brazil, Chile, Ecuador and New Zealand were purchased locally. The content of triacylglycerols, fatty acids, aliphatic and terpenic alcohols, desmethyl- methyl- and dimethyl-sterols, squalene and tocopherols were determined. The main triacylglycerols were those with ECN48. In addition, the oleic, palmitic and linoleic acids prevailed. Desmethyl-sterols were the principal minor compounds. Low amounts of aliphatic and terpenic alcohols were also found. Squalene concentrations were higher in Bacon, Fuerte and Pinkerton oils than in the other oils. The most abundant tocopherol was α-tocopherol. Partial least squares discriminant analysis made it possible to express the differences among the samples. To summarize, this work brings a different approach to the complete characterization of avocado oil.

Chemical Characterization of Major and Minor Compounds of Nut Oils: Almond, Hazelnut, and Pecan Nut

The aim of this work was to characterize the major and minor compounds of laboratory-extracted and commercial oils from sweet almond, hazelnut, and pecan nut. Oils from sweet almond, hazelnut, and pecan nut were obtained by means of an expeller system, while the corresponding commercial oils were provided from Vital Âtman (BR). The contents of triacylglycerols, fatty acids, aliphatic and terpenic alcohols, desmethyl-, methyl-, and dimethylsterols, squalene, and tocopherols were determined. Oleic, palmitic, and linoleic acids were the main fatty acids. Desmethylsterols were the principal minor compounds withβ-sitosterol being the most abundant component. Low amounts of aliphatic and terpenic alcohols were also found. The major tocopherol in hazelnut and sweet almond oils wasα-tocopherol, whereasγ-tocopherol prevailed in pecan nut oil. Principal component analysis made it possible for us to differentiate among samples, as well as to distinguish between commercial and laboratory-extracted oils. Heatmap highlighted the main variables featuring each sample. Globally, these results have brought a new approach on nut oil characterization.