Strawberry aldehydes

Suggest a synthesis for the perfumery compound strawberry aldehyde (21) - not of course an aldehyde at all. 

Ethyl 3-methyl-3-phenylglycidate [77-83-8], so-called aldehyde Cie , strawberry aldehyde... 

Synonyms cas 77-83-8 C-ie aldehyde EMPG a-p-EPOXY-p-METHYLHYDROCINNAMIC acid, ethyl ester ETHYLa,p-EPOXY-p-METHYLHYDROCINNAMATE ETHYL 2,3-EP0XY-3-METHYL-3-PHENYLPR0PI0NATE ETHYL ESTEROf 2,3-EPOXY-3-PHENYLBUTANOIC ACID FRAESEOL 3-METHYL-3-PHENYLGLYCIDIC ACID ETHYL ESTER STRAWBERRY ALDEHYDE... 

Ethyl 2,3-epoxy-3-methyl-3-phenylpropionate Ethyl 3-methyl-3-phenylglycidate Ethyl 3-methyl-3-phenyloxiranecarboxylate 3-Methyl-3-phenyl glycidic acid ethyl ester 3-Methyl-3-phenyloxiranecarboxylic acid, ethyl ester Oxiranecarboxylic acid, 3-methyl-3-phenyl-, ethyl ester Strawberry aldehyde Ciassification Organic compd. 

Stractan. See Arabinogalactan Straight-run kerosene Straight-run kerosine. See Kerosene Strained honey. See Honey Stratos . See Cycloxydim Strawberry aldehyde. See Ethyl methylphenylglycidate Strawberry furanone. See 4-Hydroxy-2,5-dimethyl-3(2H) furanone Strawberry tree extract. See Arbutus unedo extract... 

By long tradition certain compounds are commonly known by names such as aldehyde Cjs or strawberry aldehyde, aldehyde C14, or peach aldehyde. While the sensory description is accurate, the chemical designation is not. Aldehyde C,g is in fact ethyl 2,3-epoxy-3-phenyl-butanoate whereas aldehyde ,4 is 4-hydroxy unde-canoic acid, a y-lactone. 

The berry or the small fruits consist of strawberry, raspberry, blackberry, black currant, blueberry, cranberry and elderberry. The volatiles responsible for the flavour of small fruits are esters, alcohols, ketones, aldehydes, terpenoids, furanones and sulfur compounds (Table 7.3, Figs. 7.1-7.7). As fruit ripen, the concentration of aroma volatiles rapidly increases, closely following pigment formation [43]. 

Sugars, acids and aroma compounds contribute to the characteristic strawberry flavour [85]. Over 360 different volatile compounds have been identified in strawberry fruit [35]. Strawberry aroma is composed predominately of esters (25-90% of the total volatile mass in ripe strawberry fruit) with alcohols, ketones, lactones and aldehydes being present in smaller quantities [85]. Esters provide a fruity and floral characteristic to the aroma [35,86], but aldehydes and furanones also contribute to the strawberry aroma [85, 87]. Terpenoids and sulfur compounds may also have a significant impact on the characteristic strawberry fruit aroma although they normally only make up a small portion of the strawberry volatile compounds [88, 89]. Sulfur compounds, e.g. methanethiol. 

A comprehensive study of the volatiles from strawberries was conducted by McFadden et al. (236). Over 150 components were detected, and the major volatiles were identified from strawberries. The major components included alcohols, esters, acetals, aldehydes, furfural, methyl furfural, aromatic aldehydes, and ketones. 

Lipoxygenase Bean, potato, tomato, maize, strawberry, canola, fish, meat Oxidation of polyunsaturated fatty acids to hydroperoxides and further into aldehydes, acids, ketones, etc. 

Biologically generated aromas are frequently quite complex and include a wide range of polarities. For example, strawberries have been shown to possess more than 350 volatile compounds ( 1). In addition, the classes of compounds frequently encountered in biological materials includes alcohols, aldehydes, ketones, esters, ethers, sulfides, mercaptans, amines, aromatic and heterocyclic compounds and hydrocarbons. Representative classes of compounds identified in strawberries are indicated in Table I. 

Hatanaka shows in detail the reaction scheme in plants whereby linolenic acid is converted via lipoxygenase and lyase enzymes to cis-3-hexenal. This is subsequently converted by other enzyme systems to leaf aldehyde and leaf alcohol. These three aroma chemicals are important "green" aroma notes in strawberries and other berries. If these enzymes were commercially available, then the production of natural cis-3-hexenal from inexpensive vegetable oil is theoretically feasible. 

Experiments, such as qualitative analysis of ions via precipitation with a cation or anion [3], the isolation of banana (or strawberry) DNA [4], creating a DNA alias [5], coagulation of milk [6], examining reactions for exothermic or endothermic properties [7], follens test for aldehydes [8] and the conversion of copper pennies to silver [9] have been completed by the participating students. 

The aroma of strawberries is due in part to methyl hexanoate. Ethyl butanoate contributes to the aroma of pineapple. Most natural aromas and flavors are mixtures of esters, aldehydes, and alcohols. 

Application of AA vapour has been shown to lead to major changes in fruitripening processes in non-climacteric and climacteric fruit (Fidler 1968). Yamashita et al. (1975,1976) showed that intact strawberries were able to synthesize carboxylic esters on addition of alcohols and acids or aldehydes and acids. In... 

Rhizopus stolonifer on strawberries and grapes and of Penicillium expansum on apples has been achieved by AA treatment (Prasad and Stadelbacher 1974 Stadelbacher and Prasad 1974 Morris et al. 1979 Avissar and Pesis 1991). Fumigation with other aldehydes, such as propanal and butanal has also proved effective in controlling decay in sweet cherry (Mattheis and Roberts 1993). 

Yamashita I, Nemoto Y, Yoshikawa S (1976) Formation of volatile alcohols and esters from aldehydes in strawberries. Phytochemistry 15 1633-1637... 

Yamashita I, Naito S, Lino K, Yoshikawa S (1978) Formation of aldehydes and alcohols from a-keto acids in strawberries. Nippon Shokuhin Kogyo Gakkaishi 25 378-382... 

But the smell is special it is said that Beaux believed that he had created something that reminded him of snow-covered Russian landscapes. Others have compared its effect on the perfume to lemon juice on strawberries . And that is down to the aldehydes, especially 2-methylundecanal. 

Nowadays, more than 400 compounds forming the large-fruited strawberry Fragaria ananassa and other hybrids, Rosaceae) flavour are known, yet the importance of many of them is not yet fuhy understood. Besides a number of esters (mainly butanoates) and aldehydes, such as (Z)-hex-3-enal, which generally have green and fruity flavours, 4-hydroxy-2,5-dimethyl-2 f-furan-3-one (furaneol, also known as strawberry or pineapple furanone) and its methyl ether 4-methoxy-2,5-dimethyl-2 f-furan-3-one... 

Pineapple Ananas comosus, Bromeliaceae) aroma consists of about 200 alcohols, esters, lactones, aldehydes, ketones, monoterpenes, sesquiterpenes and other volatiles. About 80% of the total volatile substances are esters. The main components in the green fruit are ethyl acetate, ethyl 3-(methylthio)propionate (8-189) with a distinctive pineapple aroma and ethyl 3-(acetoxy)hexanoate (8-190). The ripe fruit contains, as the main esters, ethyl acetate, (2J ,3i )-butane-2,3-diol diacetate (8-191) and ketone 3-hydroxy-butan-2-one. An important compound for the typical character of pineapple aroma, as in strawberry aroma, is 2,5-dimethyl-4-hydroxy-2//-furan-3-one (furaneol), present as a glycoside, and 2,5-dimethyl-4-methoxy-2H-furan-3-one. 

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