Dimethyl 9-Octadecenedioate and 9-Oktadecene from Methyl Oleate Via a Ruthenium-Catalyzed Homo Olefin Metathesis Reaction

Oleic acid, one of the major components of palm oil, has attracted much interest in modern oleochemistry. The internal olefin group in oleic acid is a useful functional group in the transformation of a fatty acid to other functional chemicals and materials. In this paper, we discuss the application of the olefin metathesis reaction by preparing a long-chain dicarboxylic acid and alkene from the ester of oleic acid. The internal olefin metathesis reaction of methyl oleate produced dimethyl 9-oktadecendioate and 9-octadecene in the presence of a ruthenium Grubbs II (second generation) catalyst with a 51% yield. We also found that there was a higher amount of the E isomer products than the Z isomer products.

Dimethyl 9-oktadecenedioate; Methyl oleate; Olefin metathesis; 9-oktadecene

The homo olefin metathesis of methyl oleate was successfully carried out using a Grubbs II catalyst. The products were 9-octadecene and dimethyl 9-octadecendioate. Both products exist as a mixture of geometrical isomers, and the ratio of E/Z isomers is 8:2. The best yield was achieved by using only 1 mL of solvent and 1 mL of methyl oleate, which gave a 51% yield. It was also demonstrated that this homo olefin metathesis does not require much of the catalyst, since the decrease in yield that accompanies the decrease in the amount of catalyst was not very significant. This paper showed a promising start in developing the derivatization of palm-oil products in Indonesia.

The authors would like to thank Badan Pengelola Dana Perkebunan Kelapa Sawit (BPDPKS) for funding this research.