Abstract: The present invention relates to a process for preparing triethylenediamine (TEDA) derivatives, comprising the following steps: a) reacting a dihydropyrazine with an olefin, b) if appropriate hydrogenating after step a). The present invention further also relates to novel TEDA derivatives as such and to their use as incorporable polyurethane catalysts.

Abstract: The present invention relates to a process for resolving racemates of alkoxy-substituted primary amines by reacting with an ester in the presence of a lipase and subsequently separating the optically active amide which is formed from the unreacted optically active amine. This is followed where appropriate by hydrolysis of the optically active amide, separation of the optically active amine produced thereby from the acid from which the ester is derived, racemization and recycling of the unwanted enantiomer of the amine, and esterification and recycling of the acid.

Abstract: The process for purifying an .alpha.-, .beta.- or .gamma.-substituted carboxylic acid or a salt or an ester thereof or a mixture of two or more thereof from an aqueous solution which contains an .alpha.-, .beta.- or .gamma.-substituted carboxylic acid or a salt or an ester thereof or a mixture of two or more thereof and at least one polyol or at least one amino alcohol, wherein the solution is treated by electrodialysis.