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3 Polish Journal of Chemical Technology

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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

2016

Vol. 18, nr 4

90--95

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.

LiOO.H2O as a catalyst for Knoevenagel and Gewald reactions

Gouda M. A.

Polish Journal of Chemical Technology

2010

Vol. 12, nr 4

31-35

Commercial available lithium hydroxide monohydrate LiOH.H 2O was found to be a novel 'dual activation' catalyst for tandem cross Knoevenagel condensation between malononitrile or ethylcyanoacetate and aromatic aldehydes leading to an efficient and easy synthesis of the corresponding arylidenes at room temperature in a short reaction time. In the case of salicyaldehyde the reaction lead to the formation of 3-substituted coumarins. The high efficacy, cheapness and easy availability of LiOH.H2O prompted us to investigate its validity as a basic catalyst for Gewald reaction.

Through Knoevenagel synthesis of coumarines to methcrylate monomers containing optical active groups

Bogdał D., Stępień I., Pajda M.

Polish Journal of Chemical Technology

2003

Vol. 5, nr 3

90-92

Coumarines are compounds originating from the nature, used in many areas such as cosmetics, seasonings, pharmaceutics, and photochemistry. There are many developed methods of coumarines synthesis, e.g. Pechman reaction, Perkin reaction, Knoevenagel condensation and many others. Since coumarine derivatives have been studied in our laboratory, we have investigated their synthesis through Knoevenagel condensation. 3-carboxycoumarines were synthesized from appropriate hydroxybenzealdehydes and then their methacrylate monomers were synthetised using 2-hydroxyethyl methacrylate. All compounds were identified by GC-MS and IR and gave satisfactory results in comparison with authentic samples. Described in this paper series of monomers were copolymerised with other monomers to give photo- and electroluminescent copolymers.