Dendrimer-based catalyst containing lanthanum and organic amine for aldol condensation

Abstract

This paper reported on the synthesized and characterization of dendrimer-based basic catalyst and their application in catalysis. The PAMAM dendrimers (G0.5, G1.0, G1.5 and G2.0) were synthesis via divergent method by using reagent excess method starting from ethylenediamaine (EDA) followed by consecutive Michael addition and ester amidation reaction with methanol as solvent. The synthesized PAMAM dendrimer were coupled with lanthanum(III) nitrate hexahydrate and tertiary amine by using sodium borohydrate (NaBH4) as reducing agent to yield the corresponding catalysts with higher catalyst reactivity. The synthesized catalyst been characterized by using Fourier Transform Infrared (FTIR) Spectroscopy, Ultraviolet-visible Diffuse Reflectance (UV-Vis DR) and Field Emission Scanning Electron Mic roscopy (FESEM). The prepared catalyzed were tested in the asymmetric aldol condensation comprising the hydroxyacetone-based aldol reaction to provide 3,4-dihydroxy-4-phenylbutan-2-one which is significance in medicine. Keywords:PAMAM dendrimer, lanthanum, organic amine, aldol condensation.