Thiol 3-methylbutane

Authentic skunk spray has become valuable for use in scent-masking products. Show how you would synthesize the two major components of skunk spray (3-methylbutane- 1-thiol and but-2-ene- 1-thiol) from any of the readily available butenes or from buta-1,3-diene. 

Figure 13.2.1 2-Butene-1-thiol, an odiferous component of a skunk s secretion. methylbutane-1-thiol (Fig 13.2.2.)J21...

Individually indexed compounds are f Butanethiol, 1712 f 2-Butanethiol, 1713 Dodecanethiol, 3567 f Ethanethiol, 0933 f Methanethiol, 0489 f 2-Methylbutane-2-thiol, 2023 f 3-Methylbutanethiol, 2024 f 2-Methylpropanethiol, 1715 f 2-Methyl-2-propanethiol, 1716... 

Striped skunk defensive secretion contains a number of compounds but two are largely responsible for the odor tra 5 -2-buten-l-thiol and 3-methylbutane-l-thiol ... 

Draw as a Newman projection ( )-2-methylbutane-l-thiol with an antiperi-planar conformation along the C1-C2 bond. 

The odor of thiols is their strongest characteristic. Skunk scent is composed mainly of 3-methylbutane-l-thiol and but-2-ene-l-thiol, with small amounts of other thiols. Ethanethiol is added to natural gas (odorless methane) to give it the characteristic gassy odor for detecting leaks. 

Human beings can detect and distinguish thousands of different compounds by smell, often with considerable sensitivity and specificity. Most odorants are relatively small organic compounds with sufficient volatility that they can be carried as vapors into the nose. For example, a major component responsible for the smell of almonds is the simple aromatic compound benzaldehyde, whereas the sulfhydryl compound 3-methylbutane-l-thiol is a major component of the smell of skunks. 

C5H10I2 1,1 -diiodo-2-methylbutane 66688-50-4 499.20 43.345 2 5484 C5H10OS 2-methyltetrahydrofuran-3-thiol, mixed isome 57124-87-5 443.15 38.450 1.2... 

In the first redox process (Equation 1), instead of focusing on the iodine itself, the formation of the by-product, that is, HI, is scrutinized because an efficient thiol oxidation depends on HI removal by a base, or its dissolution in a biphasic reaction mixture. Thus, in a reaction monitored by H NMR, 1,3-propanethiol (1 mmol) was quantitatively oxidized to dithiolane 2 with iodine (0.5 mmol) in the presence of 2-methy 1-2-butene (1 mmol), which was completely converted into 2-iodo-2-methylbutane by HI formed in situ. In this case, as well as with thioacetic acid, the same alkene was completely converted by HI to 2-iodo-2-methylbutane, while in an absence of the butene derivative the corresponding disulfides were not detected. 

Sulfonic acids may also be obtained by oxidation of the appropriate thiols (see Chapter 4, p. 43). The oxidants may be halogens, hydrogen peroxide, nitric acid, potassium permanganate or chromic anhydride (Scheme 27). An illustrative example is provided by the oxidation of 4-chloro-2-methylbutane-2-thiol (47) to the corresponding sulfonic acid (48) (Scheme 27). 

Q.6) 1-Butanethiol, 3-methyl-, 3-methylbutane-l-thiol, isopentyl mercaptan [541-31-1] FEMA 3858... 

Second, almost all of the low-molecular-weight sulfur compounds have objectionable (to humans) odors. Thus, in defense, the skunk sprays offenders with a mixture of thiols (and other compounds) containing the disulfide, (E)-2-buten-l-yl methyl disulfide, and the thiols 1-butane thiol, 3-methylbutane-l-thiol, and ( )-2-butene-l-thiol. Additionally, although the mixture of low-molecular-weight hydrocarbons used as natural gas is essentially odorless (to humans), contamination of that material with only a few parts per billion (ppb) of a mixture of low-molecular-weight (mostly Cs-isomers) thiols is sufficient to allow humans to smell a gas leak. ... 

Many applications of Kilpatrick and Pitzer s procedure for calculating thermodynamic properties of molecules with compound rotation have been reported. In all cases possible potential energy cross-terms between rotating tops have been neglected. Contributions from internal rotation of symmetric tops have been calculated using the appropriate tables." These tables have also been used in calculations for the internal rotation of asymmetric tops hindered by a simple -fold cosine potential. 3-Fold potential barriers have been assumed in calculations for the —OH rotations in propanol and 1-methylpropanol, the —SH rotations in propane-1-thiol, butane-2-thiol, 2-methylpropane-l-thiol, and 2-methylbutane-2-thiol, the C—S skeletal rotations in ethyl methyl sulphide, diethyl sulphide, isopropyl methyl sulphide, and t-butyl methyl sulphide, and the C—C skeletal rotations in 2,3-dimethylbutane, and 2-methylpropane-l-thiol. 2-Fold cosine potential barriers have been assumed in calculations in the S—S skeletal rotations in dimethyl disulphide and diethyl disulphide. ... 

The classical approximation described on p. 294 by equations (26), (27), and (28) has been used for calculating thermodynamic contributions for the C—C skeletal rotation in 2-methylbutane, and for the C—S skeletal rotation in diethyl disulphide, by using assumed restricting potentials. Contributions from the skeletal torsion in 2-methylbutane-2-thiol and... 

A similar treatment of the torsion of other groups (e.g. of one methyl group in butane-2-thiol, both methyl groups in 2-methylpropane-l-thiol, and of the ethyl group in 2-methylbutane-2-thiol) as anharmonic oscillators has been adopted in recent work. ... 

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