THE NON-CATALYTIC AND CATALYTIC INTERACTION OF ETHANOLAMINE AND 2-ETHYLHEXANOIC ACІD

Alkanolamides and aminoesters are obtained by interacting carboxylic acids, their esters, or carboxylic acids chloranhydrides with ethanolamines. Non-catalytical conditions and catalysis by homogeneous and heterogeneous catalysts and enzymes are used. The regularities of non-catalytic and catalyzed by homogeneous and heterogeneous acids and bases interaction between ethanolamine and 2-ethylhexanoic acid have been studied. p-Toluenesulfonic acid, potassium hydroxide, H-cation exchange resin KU-2-8, and OH-anion exchange resin AV-17-8 were used for the catalysis of reactions in non-stationary conditions. Control of the reaction was carried out by the amount of water formed, determined by chromatographic analysis, and the amine number of the reaction products, determined by potentiometric titration, respectively. It was established that the mixing of monoethanolamine and 2-ethylhexanoic acid is accompanied by the release of a significant amount of heat, apparently due to the reaction of an ethanol ammonium salt formation. Homogeneous catalysts, unlike ion-exchange resins, significantly accelerate its disintegration. Particularly, by an almost equivalent ratio of reagents and a temperature of 150–155 oC in 80 min the conversion of 2-ethylhexanoic acid in the non-catalytic reaction is 15 %, and in reaction catalyzed by p-toluenesulfonic acid, potassium hydroxide, H-cation exchange resin, and OH-anion exchange resin is 30, 22, 14, and 18 %, respectively. It was established that the main product of the interaction between ethanolamine and 2-ethylhexanoic acid is 2-(N-hydroxyethyl)-2-ethylhexanamide. A comparison of the amount of water released and the change in the amine number also indicates the esterification of 2-ethylhexanoic acid with methanolamine catalyzed by p-toluenesulfonic acid, potassium hydroxide, and OH-anion exchange resin.