Síntese e Caracterização de Derivados Fluorados de Chalcona

Resumo

Chalcones are natural compounds formed by an α, β-unsaturated carbonyl system that joins two aromatic
rings forming the central core of many biologically important compounds. They are the biogenetic
precursors of flavonoids and isoflavonoids found abundantly in plants. The chalcone class is of great
interest not only from a biosynthetic perspective, but also because due to its broad biological activities. In
this sense, the present investigation focuses on the synthesis and characterization of pyrazole compounds
derived from chalcones, namely the 1-(5-(2,6-difluorophenyl)-4,5-dihydro-3-p-tolylpyrazol-1-yl)ethenone
and 1-(5-(2,6-difluorophenyl)-3-(furan-2-yl)-4,5-dihydropyrazol-1-yl)ethanone. The chalcone precursors
were obtained through an aldol condensation reaction with aromatic aldehydes and aromatic ketones by
the Claisen-Schmidt condensation. For the pyrazole derivatives synthesis, an easy, safe and effective
method was achieved by heating assisted by microwave irradiation reactor, through the reaction of
chalcone and hydrazine in acetic acid. The use of microwaves allowed a high yield of the product in a
short reaction time. All products, chalcones and pyrazole derivatives, were then characterized by Infrared
(IR) spectrometry, Gas chromatography–Mass Spectrometry (GC-MS) and 1H and 13C Nuclear Magnetic
Resonance (NMR) spectrometry.