Location: Bio-oils ResearchTitle: Formation of furan fatty alkyl esters from their bis-epoxide fatty esters Author
Submitted to: Journal of the American Oil Chemists' Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/15/2014
Publication Date: 11/21/2014
Publication URL: http://handle.nal.usda.gov/10113/60473
Citation: Bantchev, G.B., Doll, K.M., Biresaw, G., Vermillion, K. 2014. Formation of furan fatty alkyl esters from their bis-epoxide fatty esters. Journal of the American Oil Chemists' Society. 91:2117-2123.
Interpretive Summary: Reactions of epoxidized vegetable oils with different alcohols are used for synthesis of biobased lubricating oils and polymer precursors. Although there are numerous publications on the topic, the products have still not been investigated in detail. Instead, many authors have assumed structures that have been extrapolated from the reaction of the much simpler epoxidized methyl oleate. A team of ARS scientists in Peoria, IL, have investigated the lubricating oil synthesis in more detail by using a more realistic system – epoxidized alkyl soyate. They have found previously unreported products – furan fatty esters (FFE) - which are not obtained in the overly simple model system, but are an important component of the actual lubricating oil. FFE were observed in yields up to 13%. The finding demonstrates the need for more careful characterization of all reactions involving epoxidized vegetable oils. Better knowledge of the products will lead to correct structure-property relationships, and will help find new applications.
Technical Abstract: Reactions of epoxidized alkyl soyate with four different alcohols: ethanol, isopropyl alcohol, 2-ethylhexanol, benzyl alcohol, in the presence of Bronsted acid catalyst, were investigated. Products that were not reported in prior studies of similar reactions were found. These were furan fatty acid alkyl esters (FFE, mixture of alkyl 8-(5-hexyl-2-furyl) octanoate and alkyl 9-(5-pentyl-2-furyl) nonanoate) which were unambiguously identified by means of GC-MS and two-dimensional NMR. Evidence suggests that the FFE are formed by an acid-catalyzed rearrangement of the epoxidized linoleates. The FFE were formed in the presence of all four alcohols tested and in the presence of either sulfuric acid or Amberlyst 15 catalyst. Yields of up to 13%, as quantified by GC and NMR spectroscopies, were observed.