3-methyl-l-butanol acetate

Methylbutan-l-ol, see Isoamyl alcohol 3-Methyl-l-butanol acetate, see Isoamyl acetate... 

METHYL-l-BUTANOL ACETATE (626-38-0) Forms explosive mixture with air (flash point 89°F/32°C). High heat may lead to instability. Reacts with strong oxidizers. Incompatible with strong acids, nitrates, strong alkalis. Attacks many plastics. 

Esters Ethyl acetate (a) 3-Methyl-l-butanol- acetate (b) ... 

Methyl-l-butanol, see Isoamyl acetate Methyl ferf-butyl ether, see Methanol A-Methylcarbamic acid, see Carbofuran... 

Immobilisation of an Acetobacter aceti strain in calcium alginate resulted in improvement of the operational stability, substrate tolerance and specific activity of the cells and 23 g phenylacetic acid was produced within 9 days of fed-batch cultivation in an airlift bioreactor [133]. Lyophilised mycelia of Aspergillus oryzae and Rhizopus oryzae have been shown to efficiently catalyse ester formation with phenylacetic acid and phenylpropanoic acid and different short-chain alkanols in organic solvent media owing to their carboxylesterase activities [134, 135] (Scheme 23.8). For instance, in n-heptane with 35 mM acid and 70 mM alcohol, the formation of ethyl acetate and propylphenyl acetate was less effective (60 and 65% conversion yield) than if alcohols with increased chain lengths were used (1-butanol 85%, 3-methyl-l-butanol 86%, 1-pentanol 91%, 1-hexanol 100%). This effect was explained by a higher chemical affinity of the longer-chain alcohols, which are more hydrophobic, to the solvent. 

Although there are strain specific variations, the principle higher alcohols involved in wine aroma ares 1-propanol, 2-methyl-l-propanol, 1-butanol, 2-phenylethanol, 2-methyl-l-butanol, 3-methyl-l-butanol, 1-hexanol, l-octanol(23). These are likely to be derived in part, from amino acids via the Erhlich pathway. Organic Acids present ares acetic, isobutyric, isovaleric, hexanoic, and decanoic(24). Aldehydes present ares acetaldehyde, isobutyraldehyde,... 

Some wine volatile compounds could be analysed, however, without previous extraction. Indeed, acetaldehyde, ethyl acetate, methanol and higher alcohols (l-prop)anol, 2-methyl-l-propanol, 2-methyl-l-butanol, 3-methyl-l-butanol and 2-phenylethanol) could be directly analysed by injecting a filtered wine spiked with a suitable internal standard e.g. 4-nonanol), in the split mode in that case, the column stationary phase should tolerate the reception of vaporized aqueous samples, e.g. GP-Wax 57 CB (100 % chemically-bonded polyethylene glycol). 

Wines produced from other minority Vitis vinifera red cultivars Castanal and Serradelo from Galicia (NW Spain) also were studied (Vilanova Martinez 2007 Vilanova et al., 2009). From the 36 compounds identified in Castanal wine, 10 were determined as the most powerful odorants P-ionone, 3-methyl-l-butanol, benzyl alcohol, 2-phenylethanol, ethyl acetate, isoamyl acetate, ethyl lactate, ethyl butyrate, ethyl hexanoate and ethyl octanoate. These data suggested Castanal wines as a fruity (blackberry) and floral (rose) product (Vilanova Martinez, 2007). In another hand, ethyl octanoate and (i-damascenone (fruity and floral aroma, respectively) were the most odorant for the red wine Serradelo form Betanzos (Vilanova et al., 2009). Ethyl octanoate and (l-damascenone were the most odorant for the Serradelo red wine. 

As the chemical equation shows, 3-methyl-l-butanol (also called isoamyl alcohol or isopentyl alcohol) was mixed with an excess of acetic acid (ethanoic acid by its systematic name) and a trace of sulfuric acid (which serves as a catalyst). This reaction is an equilibrium reaction, so it is expected that not all of the starting materials will be consumed. The equilibrium should lie quite far to the right due to the excess of acetic acid used, but not completely. 

Examples of sample handbook entries for isopentyl alcohol (3-methyl-l-butanol) and isopentyl acetate are shown in Table 4.4. 

Table 4.4 Properties of 3-Methyl-l-Butanol and Isopentyl Acetate as Listed in Lange s Handbook...

One of the problems with looking up a compound in this handbook is trying to decide the name under which the compound will be listed. For example, isopentyl alcohol can also be named as 3-methyl-l-butanol or isoamyl alcohol. In the 12th edition of the handbook, it is listed under the name isopentyl alcohol ( 5212) on page 886. Finding isopentyl acetate is an even more challenging task. It is located in the handbook under the name isoamyl acetate ( 5125) on page 876. Often, it is easier to look up the name in the name index or to find it in the formula index. 

The Aldrich Handbook is actually a catalog of chemicals sold by the Aldrich Chemical Company. The company includes in its catalog a large body of useful data on each compound that it sells. Because the catalog is reissued each year at no cost to the user, you should be able to find an old copy when the new one is issued. As you are mainly interested in the data on a particular compound and not the price, an old volume is perfectly fine. Isopentyl alcohol is listed as 3-methyl-l-butanol, and isopentyl acetate is listed as isoamyl acetate in the Aldrich Handbook. The following includes some of the properties and information listed for individual compounds. 

FIGURE 5.25 High-speed isothermal separation of a 13-component mixture without stop-flow operation (a), with a 2-s-wide stop-flow pulse to separate components (1 and 2), (b) and (c) with three stop-flow pulses to separate component pairs (1,2), (10,11), and (12,13). Vacuum outlet GC was used with an outlet pressure of 0.5 atm., and atmospheric-pressure air was used as carrier gas. Components are 1, ethyl acetate 2,2-butanone 3, benzene 4, 1-butanol 5, trichloroethylene 6, n-heptane 7, 2,5-dimethylfuran 8, 2,4-dimethylhexane 9, 3-methyl-l-butanol 10, toluene 11, 2-methylheptane 12, butyl-acetate 13, chlorobenzene. 

Banana (Musa sapientum L.) is one of the most common tropical fruits, and one of Central America s most important crops. It is grown in all tropical regions and is one of the oldest known fruits [45]. From a consumer perspective, bananas are nutritious with a pleasant flavour and are widely consumed throughout the world [57]. Esters predominate in the volatile fraction of banana (Fig. 8.2). Acetates are present in high concentrations in the fruit and generally possess a low threshold. Isopentyl acetate and isobutyl acetate are known as the two most important impact compounds of banana aroma. Alcohols are the second most important group of volatiles in banana extracts. 3-Methyl-1-butanol, 2-pentanol, 2-methyl-1-propanol, hexanol, and linalool are the alcohols present in higher concentrations in the fresh fruit [45]. 

Figure 9.9 Gas chromatogram of standard mixture of whisky congeners, conditions and column as detailed in text. Peaks (1) ethyl acetate (2) n-propanol (3) 2-methyl-1-propanol (4) n-butanol (5) 2-methyl-l-butanol. 

Acetic acid S-Methyl-l-butanol 3-Methylbutyl acetate ... 

More recently Webb et al. (1952) reported no isopropyl alcohol in a wine fusel oil sample. They did find 4.1% n-propyl, 1.9% n-butyl, 4.9% ( — )-sec-butyl, 18.3% isobutyl, 9.6% ( —)-2-methyl-l-butanol, 54% isoamyl, trace of n-amyl, 1.5% n-hexyl, 5.6% esters, and traces of acetic and butyric acids and acetal. The esters included 0.19% ethyl caproate, 0.60% ethyl caprylate, 0.52% isoamyl caprylate, 1.32% ethyl caprate, 0.38% isobutyl caprate, 0.58% ethyl laurate, 0.25% ethyl palmitate, a trace of butyrate ester, 0.06% myristate ester. Probably present were methyl salicylate, isoamyl caprate, active amyl caproate, isoamyl caproate, active amyl caprylate, isobutyl caprylate, active amyl caprate, active amyl laurate, and isoamyl laurate. 

The saturation concentration of carbon dioxide in the paint film is 0.063 mmole.cm" . In the literature values of the same order of magnitude are given for methyl acetate and 3-methyl-butanol-l 0.3 and 0.08 mmol.cm" , respectively (12). 

C17H24O, Mr 244.38, mp 35 °C, is a synthetic musk fragrance. It is prepared by Friedel-Crafts acetylation of 1,1,2,3,3,5-hexamethylindane, which can be obtained as a 70 30 mixture with l,l,3,5-tetramethyl-3-ethylindane by reacting a,p-dimethyl-styrene with amylenes or 2-methyl-2-butanol in a mixture of acetic acid and concentrated sulfuric acid [155] ... 

Fig. 14. Taft correlation with polar substituent constants (a ) of the vapour phase esterification of acetic acid with alcohols ( ) and of the olefin formation from alcohols (O) over Na-poisoned silica—alumina at 250°C [126]. 1, Methanol 2, ethanol 3, 1-propanol 4, 1-butanol 5, 2-methyl-l-propanol 6, 2-propanol 7, 2-butanol 8, 2-methyl-2-propanol.

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