Ethyl-2,4-decadienoate

CIC (Z)-3-hexenol and (E)-2-hexenal contribute to the unripe, green character hep-tyl acetate and ethyl 2,4-decadienoate impart the fruity pear note and 2,6-nonadien-l-ol adds the melon-like topnote. 

Synonyms 2,4-Decadienoic acid, ethyl ester, (E,Z)- Ethyl 2,4-decadienoate Ethyl (2E,4Z) decadienoate Ethyl (2E,4Z)-2,4-decadienoate Ethyl 2-trans-4-cis-decadienoate E,Z-Ethyl 2,4-decadienoate Ethyl trans-2-cis-4-decadienoate Ethyl trans-2-cis-4-decadienoate, mixt. of isomers Pear ester Definition One of the principle components of pear Empirical C12H20O2... 

Unsaturated esters may also be derived from the products of B-oxidation of unsaturated fatty acids. Methyl-and ethyl decadienoates are known as character impact compounds of Bartlett pears and all presumptive intermediates of the pathway were identified by Jennings et al. (JLZ UL) binoleyl-CoA is transformed into (E,Z)-2,4-decadienoyl-CoA by B-oxidation. The further degradation... 

Decadienoic acid, ethyl ester, (E,Z)-. See Ethyl decadienoate... 

Hazardous Decomp. Prods. Heated to decomp., emits acrid smoke and fumes NFPA Health 1, Flammability 3, Reactivity 0 Storage Store in cool, dry, well-ventilated area out of direct sunlight, away from heat, sparks, open flame, other ignition sources keep tightly closed Uses Extraction solvent for essential oils org. synthesis component in gasoline Manuf./Distrib. Aldrich http //www.sigma-aldrich.com, ICN Biomed. Research Prods. http //www.icnbiomed.com, TCI Am. http //www.tciamerica. com 3-Ethylcyclopentane-1,2-dione CAS 13494-08-1 EINECS/ELINCS 236-812-9 Uses Fragrance in cosmetics Ethyl decadienoate... 

Pea Pro-Tein BK Pea protein hydrolysate. See Hydrolyzed pea protein Pear ester. See Ethyl decadienoate Pearex L See Pectinase Pearl AP. See Corn (Zea mays) starch Pearl / Pearl II, Pearl III. See Bismuth oxychloride... 

Ethyl decadienoate flavoring agent, natural pear prods. 

Ethylcyclopentane-1,2-dione Ethyl decadienoate Ethyl decanoate 4-Ethyl-a,a-dimethyl benzenepropanal Ethyl ethyl hexanoate... 

Ammonium citrate dibasic 221-178-8 Ethyl decadienoate 221-188-2 Avirol SA4113 Colonial STDS Rhodapon TDS Sodium tridecyl sulfate 221-201-1 Jeffcat PMDETA... 

Ethyl 3,4-Decadienoate 3,4-Decadienoic acid, ethyl ester (9) (36186-28-4)... 

Ethyl (E,Z)-2,4-decadienoate has been prepared in several ways (a) the addition of lithium d1-( Z)-1-heptenylcuprate to ethyl proplolate (90% yield, 95% purity 27-32% overall yield based on (Z)-l-bromoheptene) (b) the reaction of 1-heptenylmagnesium bromide with ethyl (E)-P-(N,N-diethylamino)acrylate (32% yield, 89% purity), (c) the Wittig reaction of hexyltriphenylphosphonium bromide with ethyl (E)-4-oxo-2-butenoate (58% yield, 85% purity). These known methods Involving the use of organometallic reagents need anhydrous conditions at low temperatures (-8° to -40°C). The separation of triphenylphosphine oxide from the reaction mixture in a Wittig reaction is occasionally not easy. 

The present procedure offers an experimentally simple and less expensive preparation of ethyl (E,Z)-2,4-decadienoate under essentially neutral conditions. It allows large scale preparation since the starting iraterlals are not sensitive to air or moisture. In addition, the reaction proceeds stereoselactively, and the yields of product are generally high. Several examples are listed in Table 1 to show the scope of the method. 

CH3(CH2)4CH = CHCH = CHC00CH2CH3, C12H20O2, Mr 196.29, bp6i> 70-72 °C, has been identified in pears and has the typical aroma of Williams pears. Synthesis of ethyl 2-trans-4-cw-decadienoate starts from cis-l-heptenyl bromide, which is converted into a 1-heptenyllithium cuprate complex with lithium and copper iodide. Reaction with ethyl propiolate yields a mixture of 95% ethyl 2-trans-A-cis- and 5% ethyl 2-tranx-4-tranx-decadienoate. Pure ethyl 2-trans-A-cis-decadienoate is obtained by fractional distillation [25]. A biotechnological process for its preparation has been developed [26]. 

Butyl acetate Pentyl acetate Hexyl acetate 2-Methylbutyl acetate Hexyl propane ate Ethyl butanoate Butyl butanoate Hexyl butanoate Methyl 2-methylbutanoate Ethyl 2-methylbutanoate Propyl 2-methylbutanoate Butyl 2-methylbutanoate Hexyl 2-methylbutanoate Ethyl hexanoate Ethyl octanoate Ethyl ( )-2-octenoate Methyl ( ,Z)-2,4-decadienoate Ethyl ( ,Z)-2,4-decadienoate... 

Ethyl (2E,4Z) decadienoate Pear 300 Bartlett, Williams pear... 

The flavour of distillates from apple and pear is characterised by typical aroma compounds from these fruits formed by enzymatic degradation of fatty acids to C6-fragments like hexanol, trans-2-hexenol, as well as ethyl esters and acetates of hexanoic acid. In distillates of pears, especially of the variety Bartlett pear, the characteristic pear flavour is mainly dominated by the ethyl and methyl esters of frans-2-czs-4-decadienoic acid and trans-2-trans-A-decadienoic acid [27-29], The biogenesis of these monounsaturated, diunsaturated, and triunsaturated esters may be explained by -oxidation of unsaturated linoleic and linolenic acid in the fruits. The sesquiterpene compound a-farnesene, which is formed during postharvest ripening and storage of Bartlett pears [28], shows that quality and intensity of distilled pear spirits is mainly influenced by the quality and degree of ripeness of the fruits. 

Gatfield et al. [44] reported in 2001 a method to produce natural ethyl E,Z)-2,4-decadienoate, the impact compound of pear. Immobilised lipase from Candida antarctica is capable of transesterifying Stillingia oil in the presence of ethanol. By this process, a complex mixture of ethyl esters is generated. By fractional distillation, the ethyl ester of ( ,Z)-2,4-decadienoate can be isolated from the mixture in a total yield of about 5% and with a high degree of purity. As only... 

In 2004, Ley et al. [45] showed a stereoselective enzymatic synthesis of cis-pellitorine [N-isobutyldeca-(2 ,4Z)-dienamide], a taste-active alkamide naturally occurring in tarragon. The reactants were ethyl ( ,Z)-2,4-decadienoate— the pear ester described before—and isobutyl amine. The reaction is catalysed by lipase type B from Candida antarctica (commercially available), which shows a remarkable selectivity towards the 2 ,4Z ester. The yield was about 80%. 

Jennings et al (228) fractionated an extract from Bartlett pears into 32 volatile components of which five were found to contribute significantly to the characteristic pear aroma. Later studies indicated that esters of trans-2 cis-4 decadienoic acid and hexyl acetate were significant components of the Bartlett pear aroma (229, 230). More recently, numerous volatiles of Bartlett pears were separated and identified including esters of methyl, ethyl, propyl, butyl, and hexyl alcohols, and Cio to Ci8 fatty acids (231, 232). 

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