Highly efficient synthesis processes for the selective catalytic oxidation of unsaturated fatty acid methyl esters (FAMEs) are described, leading to valuable renewable platform chemicals. Here keto-FAMEs derived from methyl oleate and methyl erucate were synthesized via a cocatalyst-free Wacker oxidation process using a high pressure reactor system. The catalytic system of palladium­(II) chloride in dimethylacetamide/water enabled the oxidation of monounsaturated FAMEs in the presence of molecular oxygen as sole reoxidant with reduced amounts of solvent in shorter reaction time compared to previous reports. The high product selectivity is confirmed by two different synthesis approaches and the characterization of thereof derived products using mass spectrometry measurements (GC-MS, ESI-MS-MS). The obtained keto-FAMEs are used in a subsequent Baeyer–Villiger oxidations with m-CPBA, enabling the synthesis of diesters, thus allowing access to various platform chemicals (e.g., hydroxy-esters, fatty alcohols). Moreover, an enone derivative, which can be obtained through selective photo peroxidation of methyl oleate, is studied in the cocatalyst-free Wacker oxidation process leading to a 1,3-diketone. Additionally, the same enone is used in the Baeyer–Villiger oxidation with Oxone and m-CPBA as oxidant, allowing the highly selective synthesis of a vinyl acetate and an epoxy diester derivative, respectively.

Aromatic polyester polyols are often used in polyurethane rigid foam (PUR) and polyisocyanurate (PIR) synthesis, since they offer higher rigidity than polyether polyols. Herein, a route toward fully biobased aromatic polyester polyols was investigated using sugar-based 2,5-furandicarboxylic acid (FDCA) and diethylene glycol (DEG), enabling a direct one-step synthesis of a fully biobased aromatic polyester polyol, poly­(diethylene furanoate) (PDEF), for applications in PIR rigid foam. Therefore, reaction conditions were optimized to obtain PDEF as a processable polyol with OH values and remaining unreacted DEG similar to a commercial, petroleum-based polyol. The processability was improved by either copolymerizing 10–20 mol % of a biobased aliphatic dicarboxylic acid, like succinic acid (SA) or adipic acid (AA), maintaining the fully biobased character of the polyol, or copolymerization with phthalic acid. The fully biobased polyester polyols were successfully prepared on a 100 g scale of dicarboxylic acids. Subsequent application in PIR rigid foam showed similar density, thermal conductivity, flame behavior, and compressive strength if compared to the rigid foam obtained from a commercial polyol. Thus, fully biobased PDEF can substitute petroleum-based aromatic polyester polyols in PIR applications.

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The synthesis of medium-and short-chain aliphatic polyethers is industrially limited to the ring-opening polymerization of cyclic ethers with a high ring strain, such as oxiranes, oxetanes, or tetrahydrofuran. This structural limitation can be overcome by the gallium bromide catalyzed reduction of different polyesters into their corresponding polyethers. Herein, the scope of applicable polyesters is broadened, while the influence of the polyester structure on the reduction system is examined. The reactivity as well as side reactions, i.e., overreduction leading to chain cleavage, are shown to depend on the distance of the ester groups in the repeating unit of the polyester. Two different reducing agents, namely triethylsilane and 1,1,3,3-tetramethyldisiloxane, are studied and compared in terms of reactivity and work-up procedures, showing advantages and disadvantages depending on the reduced polyester properties. The reaction conditions are optimized and the reduction can be scaled-up to 60 g polyester. All products are thoroughly characterized.