The oxidative cleavage of alkenes leads to the formation of carboxylic acids. One of the few technical processes using this reaction is the production of azelaic acid via the ozonolysis of oleic acid. Because of the need for stoichiometric amounts of the expensive oxidant ozone, together with safety hazards, there is still a requirement for a catalytic process using a cheap and environmentally friendly oxidant. In the present work, the oxidative cleavage of methyl oleate by hydrogen peroxide was catalysed by an easily available ruthenium precursor with dipicolinic acid as ligand. The systematic optimisation of the reaction led to the formation of azelaic acid monomethyl ester in high yields amounting to 86%. The investigation of the reaction pathway showed that the reaction proceeds via a tandem reaction of epoxidation and hydrolysis of the epoxide and oxidative cleavage of the vic-diol.

The transition metal catalysed epoxidation of methyl oleate 1 by hydrogen peroxide was investigated using Ru(acac)3/dipicolinic acid as catalyst. Under optimised reaction conditions, the epoxidised methyl oleate 2 was obtained with a quantitative yield in short reaction time and under mild reaction conditions.Practical applications: Epoxidised fatty acids and their derivatives are produced by the Prilezhaev reaction and used in various applications in the chemical industry. Due to the known drawbacks of epoxidation with peroxy acids, such as hazardous handling of peracids in large quantities or the decrease of epoxide selectivity due to the formation of undesired by‐products in the acidic medium, the epoxidation of fatty acid derivatives using more convenient oxidants is still a subject of research interest. Herein, we present a simple procedure for the transition metal catalysed epoxidation of methyl oleate 1 by hydrogen peroxide in quantitative yields, and under mild reaction conditions, as a potential alternative for the production of epoxidised fatty acid derivatives.

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With the hydroaminomethylation of the natural compound limonene with ammonia an atom-economic method for the synthesis of primary amines is described. This tandem reaction allows the direct conversion of the unfunctionalized monoterpene to a valuable amine product. For the first time, ammonia served as substrate to result in a maximum primary amine yield of 25 %. To overcome unwanted side reactions, a biphasic solvent system was used, consisting of an aqueous catalyst phase and an organic product phase. As catalyst the water-soluble transition metal complex [Rh(cod)Cl] 2 /triphenylphosphine trisulfonate was chosen. In combination with the surfactant hexadecyltrimethylammonium chloride it provided a good phase interaction and the possibility for easy phase separation after the reaction.

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