The cross-metathesis of fatty acid esters derived from plant oils as renewable raw materials with methyl acrylate was studied, revealing high conversions for the synthesis of a,v-dicarboxylic acid esters, depending on the choice of catalyst. A series of unsaturated a,v-diesters (1,8-, 1,11-, 1,12-, 1,15-, and 1,20-), as well as unsaturated a-esters, was thus prepared and fully characterized. The obtained results can significantly contribute to a sustainable supply of monomers for polyester and polyamide synthesis, as well as for detergents.

Olefin metathesis, awarded with the Nobel Prize in Chemistry 2005 for Chauvin, Grubbs and Schrock, has emerged as a powerful tool for organic as well as polymer chemistry. In oleochemistry, this reaction is well known and has been applied for many decades. Examples include the functionalization of the double bonds of different oleochemicals or the (direct) polymerization of plant oils via metathesis. More recent developments, particularly the development of better and more robust catalysts, allow for highly efficient cross-metathesis reactions opening new possibilities for the direct introduction of chemical functionalities. Within this contribution, the development of metathesis in oleochemistry will be discussed, covering selfmetathesis as well as more recent developments in the field of cross-metathesis that lead to desired platform chemicals.

The preparation of a long-chain aliphatic alpha,omega-diene from plant oil derivatives and its subsequent polymerization through acyclic diene metathesis (ADMET) is described. The ADMET bulk polymerization of the thus-obtained monomer, undecyl undecenoate, was investigated and optimized by applying ruthenium-based metathesis catalysts from Grubbs and Hoveyda-Grubbs, leading to high-molecular-weight polyesters. Moreover, by applying different amounts of methyl 10-undecenoate as a chain stopper in this ADMET step growth polymerization, the molecular weight of the resulting polyester could be tuned in a range from approximately 10 to 45 kDa. Finally, the application of a poly(ethylene glycol) methyl ether acrylate as the chain stopper led to the preparation of ABA triblock copolymers in a one-step, one-pot procedure.

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The synthesis of a,w-difunctional monomers from the renewable resource oleyl alcohol via a cross-metathesis reaction with methyl acrylate is described. The reaction conditions were optimized for high conversions in combination with high cross-metathesis selectivity. The introduction of a protecting group for the alcohol functionality of oleyl alcohol was found to be a necessary step in order to significantly reduce the amount of metathesis catalyst required to obtain full conversions and good selectivities. All reaction conditions were compared to each other in a quantitative fashion with the program EATOS (environmental assessment tool for organic syntheses) revealing the environmentally most benign approach for the synthesis of the desired a,w-difunctional monomers. These calculations also clearly revealed that the introduction of the protecting group was a necessary step in order to minimize the amount of the produced waste and to use the raw materials more efficiently.