Synthesis and evaluation of the thermal behavior of flavonoids

Abstract

Flavonoids in the broad sense of the term are virtually universal plant pigments. Synthesis of flavanone and 6-hydroxyflavanone was carried out and identified by H and C NMR. Details concerning the thermal behavior were evaluated by thermogravimetry under oxygen and nitrogen purge gases. Additionally, the kinetic studies were evaluated from several heating rates (5, 10 and 20 °C min−1) and sample mass of 2 mg in open crucibles. The obtained data were evaluated with the isoconversional method, where the values of activation energy (E a/kJ mol−1) were plotted in function of the conversion degree (α). The results of thermal behavior of the flavanone under a nitrogen purge gas showed that this compound has a homogeneous degradation process while the hydroxyl group in the aromatic ring of 6-hydroxyflavanone there are two mass losses.