Hydroamination is an elegant and atom economical reaction to convert alkenes into amines. One of the few technical realisations of this reaction is the hydroamination of myrcene to diethylgeranyl-A C H T U N G T R E N N U N G amine, an important precursor of (À)-menthol. However, this so-called "Takasago process" is catalysed by high amounts of alkali metals, especially lithium, which makes it a relatively expensive approach. In the present work, the hydroamination of myrcene with morpholine is catalysed by palladium complexes with bidentate ligands such as bis(diphenylphosphino)butane (DPPB) or bis(2-diphenylphosphinophenyl) ether (DPEphos). The systematic optimisation of the reaction parameters under single-phase conditions led to yields of the 1,4-adducts of higher than 90%. The only side products proved to be the telomers of myrcene, whose formation could be decreased by using appropriate reaction conditions. The method of temperature-dependent solvent systems was successfully applied to separate the palladium catalyst from the amines with a palladium leaching lower than 1.0%.

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The unique linear linkage of isobutene to generate highly valuable C8 precursors for plasticizers is feasible by using special nickel catalysts. (4-Cyclooctene-1-yl)(1,1,1,5,5,5-hexafluoro-2,4-acetylacetonato)nickel and aluminum-alkyl-activated nickel acetylacetonates produce isobutene dimers with high selectivities of up to 95%. Moreover, selectivity for the head-to-head products (2,5-dimethylhexenes) is remarkably high at up to 99%. Additionally, novel C12 isobutene trimers are also formed with a very high selectivity of up to 99% for the linear linkage. The trimer structure (2,5,8-trimethylnonenes) reflects the stepwise characteristic of the reaction mechanism. Pathways of insertion and activation and the deactivation processes of the catalyst are discussed in detail.

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