Throughout history, and even today, there has been an ongoing interest in the perfume industry to develop new substances that enhance, alter, or improve olfactory notes to enable the production of new perfume oils. Such substances are used either to replace costly natural substances that are in limited supply and costly to produce, or to create new fragrance notes of perfume types that were previously unavailable. Since woody-smelling compounds are indispensable ingredients in perfumery, we decided to work with fragrant camphor, whose products have been sought since ancient times. It has been found that some derivatives of campholenic acid, such as esters, ketones, and alcohols with extended side chain, are extremely stable compounds with a very individual scent property and are fragrances that are versatile, especially woody, sandalwood, fruity and floral scents. In contrast, fragrances derived from (+)-isocampholenic acid have not yet been described in the literature and in this master thesis, the synthesis of various (+)-isocampholenic acid derivatives with potential olfactory properties, was carried out. The preparation of the (+)-isocampholenic acid derivatives started from commercially available (1S)-(+)-10-camphorsulfonic acid, which gave, in two synthestic steps, the starting (+)-isocampholenic acid. In the first part, the esterification of (+)-isocampholenic acid with various organohalides in the presence of K2CO3 was carried out, and the isolated esters had a pleasant woody odor, but the most surprising odor we detected was that of an ester with a marine odor. In this part, we also performed Steglich esterification of (+)-isocampholenic acid with different alcohols, EDC as coupling reagent and DMAP as catalyst. The odor of the esters was mildly fruity, woody and floral. The next step was the reduction of (+)-isocampholenic acid to primary alcohol with LiAlH4. Various acid anhydrides reacted with the prepared primary alcohol to form esters with a fruity odor. A small library of woody ethers was synthesized with Williamson synthesis using depronated primary alcohol and various organohalides. A cyclic ether was synthesized from primary alcohol and TFA, which exhibited a very pleasant peppermint odor. In this master's thesis, we also performed olfactory evaluation of the synthesized ketones, prepared from Weinreb amide and various Grignard reagents. The odor of the ketones was woody with a pleasant sweet smell. From some of the isolated ketones we prepared tertiary alcohols using methylmagnesium bromide, where we perceived the smell of forest. By epoxidation of the methylene group, we demonstrated the possibility of further functionalization of (+)-isocampholic acid derivatives. In the last part, we tested the cytotoxic activity of the synthesized fragrances.
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