@article{KreyeTothMeier2011,
  author    = {Kreye, Oliver and Toth, Tommy and Meier, Michael A. R.},
  title     = {Poly-alpha,beta-unsaturated aldehydes derived from castor oil via ADMET polymerization},
  series = {European journal of lipid science and technology},
  volume    = {113},
  journal   = {European journal of lipid science and technology},
  number    = {1},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1438-7697},
  doi       = {10.1002/ejlt.201000108},
  pages     = {31 -- 38},
  year      = {2011},
  abstract  = {10-Undecenal, derived by pyrolysis and reduction from castor oil, was almost quantitatively transformed into the corresponding aldol condensation product under basic conditions. This alpha,omega-diene monomer was polymerized using acyclic diene metathesis (ADMET) polymerization. In a catalyst screening, four of nine different ruthenium-based metathesis catalysts showed good reactivity under neat conditions at 80 degrees C in the presence of 1,4-benzoquinone and polymers with molecular weights up to 11 kDa were formed. Furthermore, the (1)H NMR spectra showed that the metathesis catalysts tolerate the alpha,beta-unsaturated aldehyde function and due to the addition of benzoquinone, the degree of double bond isomerization was low. Further experiments investigating reduced catalyst amounts (down to 0.2 mol\%) and the temperature dependence of these ADMET polymerizations gave also satisfying results for the formation of poly-alpha,beta-unsaturated aldehydes. Moreover, ADMET polymerizations with different amounts of methyl 10-undecenoate as chain-stopper were performed and the integrals of the corresponding (1)H NMR spectra allowed the determination of an absolute degree of polymerization. Finally, a reduction of a poly-alpha,beta-unsaturated aldehyde with sodium borohydride was accomplished. The resulting poly-(allyl alcohol) could be a useful compound in the generation of polymer networks like polyesters, polyurethanes, and polycarbonates and thus be of high interest in materials research.},
  language  = {en}
}
@article{BiermannMeierButteetal.2011,
  author    = {Biermann, Ursula and Meier, Michael A. R. and Butte, Werner and Metzger, J{\"u}rgen O.},
  title     = {Cross-metathesis of unsaturated triglycerides with methyl acrylate synthesis of a dimeric metathesis product},
  series = {European journal of lipid science and technology},
  volume    = {113},
  journal   = {European journal of lipid science and technology},
  number    = {1},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1438-7697},
  doi       = {10.1002/ejlt.201000109},
  pages     = {39 -- 45},
  year      = {2011},
  abstract  = {Highly functionalized dimeric triglycerides, such as compound 2, are obtained as minor products besides branched macromolecules from the acyclic triene metathesis (ATMET) polymerization of unsaturated triglycerides such as glyceryl triundec-10-enoate 1 and methyl acrylate (MA) in the presence of the second generation Hoveyda-Grubbs catalyst. The formed amount of interesting products of lower molecular weight during the ATMET reaction depends on the ratio of MA and triglyceride, reaction time, and temperature. We isolated the dimeric metathesis product 2 and synthesized the respective partially hydrogenated dimer 3 regioselectivly in a seven step reaction sequence starting from 10-undecenoic acid 7 and glycerol. Product 3 was unambiguously characterized by (13)C and (1)H NMR and MS as well as the further intermediate products of the seven step reaction including 10,11 bromo-undecanoic acid 8, the respective brominated 1,3-diglyceride 9, the brominated 1,3-triglyceride 6, and the self-metathesis products 4 and 5 which were isolated and purified.},
  language  = {en}
}
@article{deEspinosaMeier2011,
  author    = {de Espinosa, Lucas Montero and Meier, Michael A. R.},
  title     = {Synthesis of star- and block-copolymers using ADMET head-to-tail selectivity during step-growth polymerization},
  series = {Chemical communications},
  volume    = {47},
  journal   = {Chemical communications},
  number    = {6},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1359-7345},
  doi       = {10.1039/c0cc04161k},
  pages     = {1908 -- 1910},
  year      = {2011},
  abstract  = {Control over molecular architectures obtained via ADMET polymerization is limited by the step-growth nature of this technique. A new approach to this polycondensation method is described allowing for the synthesis of diblock and star-shaped polymers with molecular weight control by using the selectivity of olefin cross-metathesis between acrylates and terminal olefins.},
  language  = {en}
}
@article{vonCzapiewskiKreyeMutluetal.2013,
  author    = {von Czapiewski, Marc and Kreye, Oliver and Mutlu, Hatice and Meier, Michael A. R.},
  title     = {Cross-metathesis versus palladium-catalyzed C-H activation acetoxy ester functionalization of unsaturated fatty acid methyl esters},
  series = {European journal of lipid science and technology},
  volume    = {115},
  journal   = {European journal of lipid science and technology},
  number    = {1},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {1438-7697},
  doi       = {10.1002/ejlt.201200196},
  pages     = {76 -- 85},
  year      = {2013},
  abstract  = {Two synthetic approaches to functionalize plant oil derived platform chemicals were investigated. For this purpose, methyl 10-undecenoate, which can be obtained by pyrolysis of castor oil, was used in olefin cross-metathesis under neat conditions forming an unsaturated a,?-acetoxy ester. A catalyst screening with 11 different ruthenium-based metathesis catalysts was performed, revealing that well-suited catalysts allow for full conversion and very good cross-metathesis selectivity at a loading of only 0.5?mol\%. An alternative possibility to the aforementioned synthetic method is a palladium-catalyzed reaction of methyl 10-undecenoate with acetic acid in the presence of dimethyl sulfoxide. Here, the formation of linear and branched unsaturated acetoxy esters as well as a ketone was observed. The conversion as well as the selectivity of this procedure was studied under different reaction conditions and compared to the cross-metathesis results. Based on the successful functionalization of methyl 10-undecenoate, methyl oleate was investigated in this palladium-catalyzed C?H activation reaction. Due to the lower reactivity of the internal double bond the desired acetoxy ester was only obtained in moderate conversion in this case. In summary, this study clearly shows that palladium-catalyzed functionalization of unsaturated fatty compounds via C?H activation is an attractive alternative to the well-established olefin cross-metathesis procedure.},
  language  = {en}
}