Cinnamyl alcohol and cinnamic acid are natural compounds used in the perfume, cosmetics and pharmaceutical industries. They are best known to be found in cinnamon tree, which belongs to the family of laurels (Lauraceae). Cinnamyl alcohol and cinnamic acid are components of cinnamon essential oil, which is extracted from the leaves, bark and roots of cinnamon. Under standard conditions, cinnamyl alcohol is a white to yellowish crystalline solid, with a pleasant, floral and sweet aroma and cinnamon taste. Cinnamic acid is a white crystalline organic compound with an odour reminiscent of honey. Cinnamic acid and its derivatives are widespread in nature, but are mostly found in very low concentrations. Synthetically produced cinnamic acid is produced by the Perkin reaction.
The aim of the thesis was to synthesize derivatives of cinnamyl alcohol and cinnamic acid derivatives and and evaluate these products in an olfactory analysis. Ten of their derivatives were successfully synthesised, according to the structure of esters and ethers. One reaction did not proceed. All the products were cleaned by column adsorption chromatography, where chromatograms were developed using a mobile phase consisting of a mixture of ethyl acetate and hexane in volume ratios of 1 : 4 and 1 : 6. The success of the reactions and the identity of the products were verified by instrumental analytical methods, nuclear magnetic resonance and infrared spectroscopy. The final products were then evaluated olfactorially by an odour test, which was used to check the pleasantness and strength of aromas and their associations with other odours.
Most derivatives of cinnamyl alcohol and cinnamic acid have a pleasant smell. The average odour strength rating of the tasted samples has a weak to moderately strong odour. The odours were not constant and varied during the odour analysis. When evaluating the samples, respondents indicated cinnamyl butyrate, cinnamyl phenylacetate and cinnamyl hexyl ether as the most pleasant odours. No differences were found between respondents who use perfumes and those who do not.
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