2-Methylbutyl-3-methylbutanoate

Methylbutyl Isovalerate FEMA No. 3506 2-Methylbutyl-3-methylbutanoate 172.27/C10H20O2/ ch3 1 CH3CH2CHCH2OOCCH2CH(CH3)2 colorless liq/ herbaceous, fruity s—ale, most fixed oils ins—water/ 191°-195° ... 

Methyl Butanal, 82 2-Methylbutyl Acetate, 82 2-Methylbutyl Isovalerate, 82 2-Methylbutyl-3-methylbutanoate, 82 Methyl Butyrate, 82 2-Methylbutyric Acid, 82 Methyl Ionones, 82... 

Vespa mandarinia W-VG Alarm Pentan-2-ol 143,3-methylbutan-l-ol 144, 1-methylbutyl 3-methylbutanoate 145 [189]... 

Representatives of the subfamilies Omaliinae and Proteininae (omaliine group) possess an abdominal defensive gland reservoir that opens out between sternite 7 and 8 [ 120]. The multi-component mixtures contained in these glands are used for defence. In Omaliinae and Proteininae the secretion is characterized by mixtures of acids (e.g. 2-methylpropanoic acid, hexanoic acid, 2-octenoic acid, 2-methylbutanoic acid, 3-methylbutanoic acid, butyric acid, and tiglic acid), aldehydes (( )-2-hexenal, heptanal, octanal, nonanal), ketoaldehydes such as 4-oxo-2-hexenal 41 (Scheme 5), 6-methyl-5-hepten-2-one, alcohols (octanol, ( )-2-hexen-l-ol, 2-methylbutan-l-ol), alkanes (nonadecane), esters (2-methylbutyl tiglate 42, various propanoates, 2-hexenyl 3-methylbutanoate, 2-methylbutyl 2-methylbutanoate, octanoates,butanoates), and aromatic compounds (e.g. 2-phenethyl 3-methylbutanoate 43). Unusual compounds are 2-... 

Ethyl 2-methylbutanoate, 2-methylbutyl acetate and hexyl acetate contribute most to the characteristic aroma of Fuji apples [49]. In Red Delicious apples, ethyl butanoate, ethyl 2-methylbutanoate, propyl 2-methylbutanoate and hexyl acetate contribute to the characteristic aroma as determined by Charm-Analysis and/or AEDA [50, 51]. In a comparative study of 40 apple cultivars, the highest odour potency or Charm value was found for -damascenone [52]. This compound usually occurs in a glycosidically bound form and is present primarily in processed products owing to hydrolysis of the glycoside bond after crushing fruit cells [53]. -Damascenone has a very low odour threshold with a sweet, fruity, perfumery odour and is not typical of apple aroma in gen-... 

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... 

Methylbutanoates and methylbutyl esters are essential flavour compounds in fruit flavours they can be produced biotechnologically as mentioned before. Chowdary et al. [33] have described the production of a fruit-like flavour isoamyl isovalerate by direct esterification of isoamyl alcohol and isovaleric acid in hexane with the help of Mucor miehei lipase immobilised on a weak anion-exchange resin. 

Figure 9. Comparison of ester formation by Golden Delicious apples one day after treatment with pentanal and hexanal. 1 butyl acetate, 2 = 3-methylbutyl acetate, 3 = pentyl acetate, 4 = hexyl acetate, 5 = butyl propionate, 6 = pentyl propionate, 7 = hexyl propionate, 8 = butyl butanoate, 9 = butyl 2-methylbutanoate, 10 hexyl 2-methylbutanoate, 11 = hexyl pentanoate, 12 = hexyl hexanoate.

Alkylcarbonic acids have been separated into their enantiomers without any deriva-tization and their sequence of elution was assigned by co-injection with enantio pure references [17]. Latest results on stereoselective flavour evaluation revealed characteristic sensory properties for all the enantiomers of 2-alkylbranched acids, esters and corresponding alcohols. Tremendous differences between the mirror images of 2-methylbutanoic acid have been found. While the R-enantiomer exhibits a penetrating, cheesy-sweaty odour, the S-enantiomer emits a pleasant sweet and fine fruity note [87, 88]. All commercially available homologues of 2-methylbutanoic acid esters and 2-methylbutyl acetate are simultaneously stereoanalyzed, using heptakis (2,3-di-O-methyl-6-0-tert-butyldimethylsilyl)-P-cyclodextrin (DIME-P-CD) in PS 268 as the chiral stationary phase [88] (Eig. 6.33, Table 6.19). 

Fig, 6,33 FID chromatogram of the enantioselctive analysis of methyl 2-methylbutanoate (1), ethyl 2-methylbutanoate (2), 2-methylbutyl acetate (3), propyl 2-methylbutanoate (4), isobutyl 2-methylbutanoate (5), isopentyl 2-methylbutanoate (6), pentyl 2-methylbutanoate (7) and hexyl 2-methylbutanoate (8), simultaneously analysed by sniffing GC-see Table 6.19 (from ref [88])... 

Banana flavor Of the 350 flavor compounds identified to date in B. f. 3-methylbutyl acetate as well as 3-methylbutyl butanoate and 3-methylbutyl 3-methyl-butanoate (see fruit esters) are of particular sensory relevance. Fatty-fruity and exotic-fruity notes result mainly from aroma substances with the (Z)-4-config-uration, e.g., Z)-4-hepten-2-one (C7H12O, Mr 112.17, CAS [90605-45-1 ]) and (Z)-4-hepten-2-ol (C7H14O, Mr 114.19, CAS [34146-55-9]), as well as their acetates and butanoates. Eugenol, elemicin (see safrole), and 0-methyleugenol are responsible for the spicy aroma. Bilberry flavor The aroma of the European bilberry (Vaccinium myrtillus) is mainly due to ( )-2- hexenal, ethyl 2- and 3-methylbutanoates (see fruit esters) as well as ethyl 3-hydroxy-3-methylbutanoate (C7H,403, Mr 146.19, CAS [18267-36-2]). 

Butyl 2-methylbutanoate. See N-Butyl-2-methylbutyrate 2-Methylbutyl butyrate Butyl 3-methylbutanoate. See n-Butyl isovalerate... 

Synonyms Isoamyl 2-methylbutanoate Isopentyl 2-methylbutanoate lsopentyl-2-methylbutyrate 3-Methylbutyl 2-methylbutanoate... 

CAS 51115-64-1 EINECS/ELINCS 256-973-9 Synonyms Butyl 2-methylbutanoate n-Butyl 2-methylbutyrate 2-Methylbutyl butanoate... 

Synonyms 2-Methylbutyl 2-methylbutanoate 2-Methyl butyl 2-methyl butyrate DL-2-Methylbutyric acid 2-methylbutyl ester... 

At increased concentrations of the extract the olfactory impact of the esters notably, ethyl 2-methylbutanoate, methyl 2-methylbutanoate and 2-methylbutyl acetate become significant and presumably enhance the fruity characters that are not so dominant in the most dilute extract. The aromagram of the SDE extract itself contains forty discemable aromas and most intriguingly none of the descriptors are melon-like. 

Isoleucine 2-methylbutanol 2-methylbutyl esters 2-methylbutanoate esters 2-methylbut-2-enyl esters Banana, Apple, Strawberry Apple [202, 114-116]... 

The odors of esters are distinctly different from those of the corresponding acids. Acids have unpleasant smells, but esters have fruity smells. In fact, esters are responsible for the odors of many fruits. For example, ethyl ethanoate occurs in pineapples, 3-methylbutyl ethanoate in apples and bananas, 3-methylbutyl-3-methylbutanoate in apples, and octyl ethanoate in oranges. 

Ethyl 2-methylbutanoate Ethyl 3-methylbutanoate 3-methylbutyl acetate (isoamyl acetate) 2-propanone (acetone)... 

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