10-Undecenoate

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Laureano Oliveros - One of the best experts on this subject based on the ideXlab platform.

Cristina Minguillón - One of the best experts on this subject based on the ideXlab platform.

Michael A. R. Meier - One of the best experts on this subject based on the ideXlab platform.

  • Catalytic transesterification of cellulose in ionic liquids: Sustainable access to cellulose esters
    2020
    Co-Authors: Alexander M. Schenzel, Andrea Hufendiek, Christopher Barner-kowollik, Michael A. R. Meier
    Abstract:

    Catalytic transesterifications of cellulose were studied under homogeneous conditions using the ionic liquid 1-butyl-3-methylimidazolium chloride (BMIMCl) as a solvent. Cellulose was thus efficiently converted into cellulose esters employing various methyl esters and 10 mol% of 1,5,7-triazabicyclo[4.4.0]dec-5- ene (TBD) as catalyst. 1H NMR analysis of the products revealed up to 2.3 turnovers of the methyl esters per catalyst molecule, leading to degrees of substitution (DS) of up to 0.69. Although a comparatively low turnover number (TON) is observed, the developed methodology represents the first successful homogeneous catalytic reaction on cellulose. Furthermore, the new method is an important step forward in terms of sustainability, since the BMIMCl-DMSO mixture can be recycled and reused for the reaction, and toxic and corrosive chemicals commonly employed for cellulose esterification (such as anhydrides, acid chlorides and bromides, organic bases, all in overstoichiometric amounts) are avoided. To demonstrate the versatility of this transesterification, an aromatic (cellulose benzoate), an aliphatic (cellulose butyrate), and a fatty acid containing cellulose ester (cellulose 10-Undecenoate) were prepared. Additionally, cellulose 10-Undecenoate was successfully used for thiol-ene grafting onto reactions employing two thiols for efficient thiol-ene addition reactions. This journal is © the Partner Organisations 2014.

  • Catalytic Oxyfunctionalization of Methyl 10‐undecenoate for the Synthesis of Step‐Growth Polymers
    Macromolecular Chemistry and Physics, 2017
    Co-Authors: Marc Von Czapiewski, Michael A. R. Meier
    Abstract:

    An efficient synthesis strategy for the preparation of two renewable polyesters and one renewable polyamide via catalytic oxyfunctionalization of methyl 10-Undecenoate, a castor oil derived platform chemical, is described. The keto-fatty acid methyl ester (keto-FAME) is synthesized applying a cocatalyst-free Wacker oxidation process using a high-pressure reactor system. For this purpose, catalytic amounts of palladium chloride are used in the presence of a dimethylacetamide/water mixture and molecular oxygen as sole reoxidant. The thus derived AB monomers (hydroxy-esters, amine-ester) are synthesized from the obtained keto-FAME through Baeyer–Villiger oxidation and subsequent transesterification, reduction, or reductive amination, respectively. The resulting AB step-growth monomers are then studied in homopolymerizations using 1,5,7-triazabicyclo[4.4.0]dec-5-ene, DBU, and titanium(IV) isopropoxide as transesterification catalyst, yielding polymers with molecular weights (Mn) up to 15 kDa. The polyesters and the polyamide are carefully characterized by FTIR, SEC, 1H-NMR spectroscopy, and differential scanning calorimetry analysis.

  • Catalytic transesterification of cellulose in ionic liquids: sustainable access to cellulose esters
    Green Chemistry, 2014
    Co-Authors: Alexander M. Schenzel, Andrea Hufendiek, Christopher Barner-kowollik, Michael A. R. Meier
    Abstract:

    Catalytic transesterifications of cellulose were studied under homogeneous conditions using the ionic liquid 1-butyl-3-methylimidazolium chloride (BMIMCl) as a solvent. Cellulose was thus efficiently converted into cellulose esters employing various methyl esters and 10 mol% of 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) as catalyst. 1H NMR analysis of the products revealed up to 2.3 turnovers of the methyl esters per catalyst molecule, leading to degrees of substitution (DS) of up to 0.69. Although a comparatively low turnover number (TON) is observed, the developed methodology represents the first successful homogeneous catalytic reaction on cellulose. Furthermore, the new method is an important step forward in terms of sustainability, since the BMIMCl–DMSO mixture can be recycled and reused for the reaction, and toxic and corrosive chemicals commonly employed for cellulose esterification (such as anhydrides, acid chlorides and bromides, organic bases, all in overstoichiometric amounts) are avoided. To demonstrate the versatility of this transesterification, an aromatic (cellulose benzoate), an aliphatic (cellulose butyrate), and a fatty acid containing cellulose ester (cellulose 10-Undecenoate) were prepared. Additionally, cellulose 10-Undecenoate was successfully used for thiol–ene grafting onto reactions employing two thiols for efficient thiol–ene addition reactions.

  • Cross‐metathesis versus palladium‐catalyzed CH activation: Acetoxy ester functionalization of unsaturated fatty acid methyl esters
    European Journal of Lipid Science and Technology, 2012
    Co-Authors: Marc Von Czapiewski, Oliver Kreye, Hatice Mutlu, Michael A. R. Meier
    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.

Jürgen O. Metzger - One of the best experts on this subject based on the ideXlab platform.

Pilar Franco - One of the best experts on this subject based on the ideXlab platform.