Anais do Simpósio Latino Americano de Ciências de Alimentos
Proceedings of 14 SLACA - Latin American Symposium on Food Science

Combinatorial Chemistry (CC) is a strategic discovery for the synthesis of drugs, flavors and fine molecules of interest to several areas of industry and has been widely used for the construction of chemo-libraries. From this method, several molecules can be synthesized simultaneously and further characterized using different techniques, as well as their chemical, sensory and biological properties.1 The objective of this work was to synthesize chiral acetate esters of interest for the aroma house via combinatorial chemistry and further characterize the sensory properties by olfactory gas chromatography (GC-O). CC was used to synthesize them in a short time from racemic mixtures of 2-butanol, 2-pentanol, 3-hexanol, 2-heptanol and 2-octanol alcohols. The reaction occurred via Fisher esterification, catalyzed by H2SO4, from the mixture of reagents under stoichiometric conditions, with a total of 10 mmol of the alcohol mixture and 26 mmol of acetic acid, under reflux conditions for 20 minutes at 90 ºC. Aliquots were collected after T0, T60 and T120. The conversion and characterization of the acetate esters were carried out using the chromatographic techniques of GC-FID and GC-MS, using a chiral column β-DEX120. The results showed that ten acetate esters were synthesized by CC, that is, by the "single vessel synthesis" procedure. It was possible to obtain racemic mixtures of the (R) and (S) esters of 2-butyl, 2-pentyl, 3-hexyl, 2-heptyl and 2-octyl, with conversions ranging from 0%, 12.9%, 30.3%, 38.3% and 33.3% still in T0 and after 120 minutes, the conversions obtained were 90.0%, 87.6%, 85.7%, 87.1% and 87.3% respectively. Using combinatorial chemistry, Vermeulen and Collin2 were able to synthesize and olfactory characterize 21 mercapto esters characteristic of meat aroma. However, the olfactory characterization of these esters is still ongoing. Therefore, it appears that this CC method proved to be effective for the simultaneous obtainment of acetate esters.