Estudo das propriedades fotoluminescentes de complexos de íons lantanídeos contendo nlauroil-2-aminopiridinas.

Abstract

Currently, the research involving lanthanide ions has grown considerably, as well as its applications, since its use as in molecular devices light converters and biomarkers. In this perspective, the present work involves the synthesis, characterization and photophysical investigation of lanthanide ions complexes containing N-lauroyl-2-aminopyridines. The study was conducted through an exploratory and descriptive research. The N-lauroyl-2-aminopyridine (NL2AP) and N-lauroyl-2-aminopyrimidine (NL2APM) linkers were characterized. The complexes containing Eu3+ and Gd3+ tris-β-diketonates (4,4,4-trifluoro-1-phenyl-1,3butanedione - BTF and 1- (2-thenoyl), 3,3,3-trifluoroacetone - TTA) and amides (NL2AP and NL2APM) were characterized by thermogravimetric analysis and infrared vibrational and luminescence spectroscopies. The complexes [Eu (BTF)3(NL2APM)] and [Eu (TTA)3(NL2AP)] presented high quantum efficiency, η = 91.4 and 88.3%, respectively. All the complexes presented high values for the parameters of intensity Ω2 and Ω4, and high lifetimes, relative to the analogous series involving NA2AP (N-acetyl-2-aminopyridine) and NA2APM (N-acetyl-2aminopyrimidine). However, this is an unexpected result, since the predominance of non-radiative decay of luminescence in the compounds that present long chain. Therefore, the synthesized complexes present applicability as membrane biomarkers due to the lipophilic character and high luminescence.