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Aminokwasowe ciecze jonowe

Samaszko-Fiertek Justyna, Sowińska Kamila, Dmochowska Barbara, Ślusarz Rafał, Madaj Janusz

Wiadomości Chemiczne

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2019

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[Z] 73, 11-12

737--751

EN

Ionic liquids (IL) are defined as compounds consisting only of ions with a melting point below 100°C. [1,2,4]. The first obtained ionic liquid was ethylammonium nitrate synthesized in 1914 by Paul Walden as a result of the protonation of ethylamine with nitric acid [4]. New group of IL are amino acid ionic liquids. They are non-toxic and bio- renewable ionic liquids of natural origin. The amino acids contain at least two functional groups, an amino group and a carboxyl group, which makes them both cationic and anionic in the amino acid ionic liquid. Amino acid ionic liquids attract more and more attention in the field of catalysis, as solvents in chemical transformations and cellulose solvents due to low production costs and their biodegradable. Compounds based on imidazolium, phosphonium, ammonium and choline ionic liquids found a wide application in biological sciences, modern chemistry and materials science [10]. One of their biggest advantages is the ability to absorb CO2 (especially their amino acid derivatives), which increases the chance of eliminating carbon dioxide from the environment. Amino acid ionic liquids have also found application in the field of catalysis.

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Efficient method for Knoevenagel condensation in aqueous solution of amino acid ionic liquids (AAILs)

Ossowicz P., Rozwadowski Z., Gano M., Janus E.

Polish Journal of Chemical Technology

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2016

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Vol. 18, nr 4

90--95

EN

This work reports on the use of the amino acid ionic liquids (AAILs) which have been used as catalysts in Knoevenagel condensation of various aldehydes with malononitrile. For research we use tetrabutylammonium ionic liquids based on eight natural amino acids. The reaction was carried out in an aqueous medium. Using water as solvent provided efficient and simple method of isolation of pure product with high yield. Moreover, amino acid ionic liquid dissolved in water could be reused many times without any loss of its catalytic activity. The influence of the anion was studied. Moreover the effect of technological parameters such as: the temperature, the catalyst content, and the reaction time on yield of reaction were investigated.

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Badania stabilności termicznej aminokwasowych cieczy jonowych

Ossowicz P., Janus E.

Chemik

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2016

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Vol. 70, nr 9

481--484

PL

Porównano stabilność termiczną soli zbudowanych z aminokwasowego anionu i różnych organicznych kationów. Badania obejmowały ciecze jonowe z kationem: tetrabutyloamoniowym (TBA), tributylometyloamoniowym (tBMA), didecylodimetyloamoniowym (DDA), benzalkoniowym (BA), 2-hydroksyetylotrimetyloamoniowym (Chol) i 1-etylo-3-metyloimidazoliowym (EMIM). Zbadano wpływ kationu na stabilność termiczną dla cieczy z anionem L-leucynianowym, natomiast wpływ budowy aminokwasowego anionu określono dla soli z kationem benzalkoniowym. Dla analizowanych związków, na podstawie analizy termograwimetrycznej (krzywych TG i DTG), wyznaczono temperatury początku rozkładu, temperatury 50% ubytku masy oraz temperatury najszybszego rozkładu związku. Wykazano, że badane aminokwasowe ciecze jonowe mogą być bezpiecznie stosowane do temperatury ok. 140°C. Najwyższą stabilność termiczną wykazywał L-leucynian 1-etylo-3-metyloimidazoliowy. Badania pokazały, że zdecydowanie większy wpływ na stabilność termiczną ma rodzaj kationu. Wykazano ponadto, że pochodne aminokwasów, zawierających w łańcuchu bocznym ugrupowania aromatyczne – indolu (Trp) lub fenolu (Tyr), są termicznie najtrwalsze.

EN

We compared the thermal stability of the salt composed of amino acid anions and various organic cations. Studies included cations such as: tetrabutylammonium (TBA), tributylmethylammonium (tBMA), didecylodimethylammonium (DDA), benzalkonium (BA), (2-hydroxyethyl)trimethylammonium (choline) (Chol) and 1-ethyl-3-methylimidazolium (EMIM). We investigated the influence of the cation on the thermal stability of the ionic liquid with L-leucine anion, and the impact of the anion in amino acids ionic liquids with benzalkonium cation. Based on thermogravimetric analysis (TG curves and DTG curves) we determined initial decomposition temperatures, 50% weight loss temperatures and the fastest decomposition temperatures. It has been shown that the amino acid ionic liquids can be safely applied to a temperature of approximately 140°C. The compound with the highest decomposition temperature is 1-ethyl-3-methylimidazolium L-leucinate. Studies showed that type of cation affects on the thermal stability. It was also demonstrated that amino acid derivatives containing the aromatic moieties – indole (in Trp) or phenol (in Tyr), reveal the highest thermally stability.