The homogeneously catalyzed reductive amination of the long-chain aldehyde undecanal with diethylamine was performed in an aqueous microemulsion system using the non-ionic surfactant Marlophen NP8. The experiments showed that the used water-soluble rhodium/SulfoXantphos catalyst system is suitable for this reaction. The Rh-catalyzed formation of the alcohol by-product can be completely suppressed by the use of carbon monoxide with its stabilizing effect of the catalyst system. In addition to pressure and temperature, the most important parameters for the reaction performance of the reductive amination are the concentrations of reactants. Especially, the initial concentration of the aldehyde has a strong impact on the chemoselectivity, and the formation of aldol by-product due to the fact that both, the enamine condensation and the aldol condensation are equilibrium reactions.

The hydroaminomethylation of the long-chain olefin 1-decene and diethylamine with a homogeneous Rh(acac)(cod)/SulfoXantphos catalyst complex as a one-pot synthesis was investigated. The influence of reaction conditions such as temperature and synthesis gas pressure was determined, as well as the effects of the initial concentrations of catalyst precursor, ligand, and reactants on the yield of fatty amine. Hydroaminomethylation was successfully carried out in an aqueous microemulsion system using a non-ionic surfactant with a reaction time of 2 h. A maximum yield of 34%, high regioselectivities >97%, and chemoselectivities >85% were achieved.