ARS | Publication request: Synthesis of Branched Methyl Hydroxy Stearates Including an Ester from Bio-Based Levulinic Acid

Submitted to: Industrial and Engineering Chemistry Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 13, 2007
Publication Date: April 6, 2007
Citation: Doll, K.M., Sharma, B.K., Erhan, S.Z. 2007. Synthesis of branched methyl hydroxy stearates including an ester from bio-based levulinic acid. Industrial and Engineering Chemistry Research. 46:3513-3519.

Interpretive Summary: We have synthesized a series of compounds from the vegetable oil derived substance, methyl oleate. The compounds we derived have a structure in which there is a side chain bound to the middle of the long chain fatty ester. This changes the properties of the molecule making it more useful as a starting material for surfactant (surface active material, i.e. soap) use. The material may also be useful as an additive in vegetable oil based lubricants, giving them better surface lubricity and flow properties. In one of the reactions, another bio-based material, levulinic acid, is also used, leading to a product that is completely bio-based. Our reaction used an environmentally friendly peroxide method and the second step can be performed without added catalyst. This research benefits the vegetable oil industry by helping to open markets for vegetable oil derived fatty materials and industries where an environmentally friendly lubricant (such as forestry) would be ideal.

Technical Abstract: We report the synthesis of 5 useful branched methyl alpha-hydroxy oleate esters from commercially available methyl oleate and common organic acids. Of special interest is the synthesis utilizing the natural byproduct, levulinic acid. The other common organic acids used herein were propionic acid, hexanoic acid, octanoic acid, and 2-ethylhexanoic acid. The kinetics of the ring opening reaction were studied under pseudo 1st order conditions in the propionic acid system. An Arrhenius activation energy of 62.5 kJ mol-1 (14.9 kcal mol-1) was found. These products may prove useful in the synthesis of agriculturally based surfactants and lubricants.