Olefin cross-metathesis reactions

Before the reaction, toluene was purified, dehydrated, and purged with N₂ for 24 h. 5 g of vegetable oil methyl ester and 3 mol% of the first generation Grubbs’ catalyst were added in a well-dried flask containing 30 mL of super-dried toluene. Ethene was subsequently blown into the reaction system, stirred at 40 °C. The catalyst and the products were separated by flash chromatography. The products were characterized by GC–MS.

The conversion was calculated as the weight of methyl oleate in the products divided by the weight of methyl oleate in the feedstock, which means the transformed methyl oleate in the metathesis reaction. The selectivity was calculated as the total weight of methyl dec-9-enoate and 1-decene in liquid products divided by the theoretical total weight of dec-9-enoate and 1-decene from methyl oleate, which indicated the selectivity of the catalyst in the metathesis reaction. The yield was calculated by conversion time selectivity, which represented the catalyst efficiency of transforming methyl oleate and ethylene to desired methyl dec-9-enoate and 1-decene.

The formulas for the conversion and selectivity calculation are as follows: