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Ethyl (E,Z)-2,4-decadienoate (FEMA# 3148, CAS# 3025-30-7), or pear ester, is a colorless liquid with a highly intense green odor, which occurs naturally in apple, Bartlett pear, Concord grape, beer, pear brandy and quince. It has a green, fruity, apple odor, with tropical nuances and a juicy, ripe pear, sweet, very fruity flavor. The ester's uses in flavors include fruity red, fruity yellow, fruity tropical and other fruity applications. In fragrances, it uses encompass fruity compounds for alcoholic and cosmetic perfumes.
Ethyl (E,Z)-2,4-decadienoate is prepared from cis- 1-heptenyl bromide, which is converted to 1-heptenyl lithum cuprate complex with lithium and copper iodide.1 Further reaction of the lithium cuprate complex with ethyl propiolate yields a mixture of isomeric esters. The product is not pure and contains min. 92% of the 2E,4Z-isomer.
Ethyl (E,Z)-2,4-decadienoate is also prepared by enzymatic esterification of other (2E,4Z)-deca-2,4-dienoate esters with lipase obtained from Candida antarctica in the presence of ethanol.2 Ethyl (E,Z)-2,4-decadienoate is also used in blackcurrant odorants, which are powerful materials. For example, a blackcurrant note joins the pear-musk theme in Courreges 2020 (Andre Couregges, 1997). In this perfume, the pear note is mainly a consequence of about 5% of ethyl (2E,4E)-deca-2,4-dienoate. Pear ester is another version of the simple ester hexyl acetate (FEMA# 2565, CAS# 142-92-7), having a sweet, fruity, estery odor similar to pear.