L-butanethiol

The secretion of the anal glands of skunks epitomizes mammalian defense secretions. Sulfur compovmds in the scent of striped skunk Mephitis mephitis) include rra 5-2-butene-l-thiol, 3-methyl-l-butanethiol (Andersen and Bernstein, 1975), rra 5-2-butenyl thioacetate, 3-methylbutanyl thioacetate, and 2-quinolinemethane thiol (Wood, 1990 Fig. 10.9). The thiols, once called mercaptans (because they captured mercury atoms), are like alcohols with a sulfur atom in place of the oxygen. In the striped skvmk, the thioacetates break down in water. They yield thiols, which have the more potent, characteristic skunk odor and linger for up to 2 weeks. In the spotted skunk, by contrast, the... 

A physical characteristic is their odor 2-butene-1-thiol, CH,CH=CHCH2SH, and 3-methyl-l-butanethiol, CH3CH(CH,)CH2CH2SH, contribute to skunk smell. 

Self-Test C.1B Draw the structural formulas of (a) 2-methyl-l-butanethiol, CH3CH2CH(CH3)CH2SH, which is used to synthesize organic compounds and (b) diethyl ether (13), which has been used as a surgical anesthetic. 

Methyl-l-butanethiol (Isopentyl mercaptan) ch3ch(ch3)ch2ch2sh... 

As shown in the case of l-octen-3-one in the beginning of this chapter, aroma-active compounds show an interesting indication as media in human-environment interactions the role of this often disliked compound has some similarity to alarm pheromones. Flavor or smell of food can be categorized into food attractant molecules from this point of view. Infants are able to recognize the body odor of their mother and are attracted to it.189 An opposite example is represented by the notorious ability of skunks to spray, in which thiol compounds such as (E)-2-butene-1 -thiol and 3-methyl-l-butanethiol are used as potent repellents190(see Chapter 4.09). 

Pyrrole 843 (R = Me) was formed in moderate yield (30%) by treatment of 3,4-dibromo pyrrole 842 with Bu"Li and then with dimethyl disulfide. Pyrrole 843 (R = Bu") was prepared according to Klingsberg s method, by treatment of dibromide 842 with copper(l) -butanethiolate in a mixture of quinoline and pyridine to give the desired product in 33% yield. In both cases, the monosubstituted derivatives 844 were obtained as intermediates in 45% and 10.5% yields, respectively. 

The most obvious characteristic of thiols is their appalling odor. Skunk scen for example, is caused primarily by the simple thiols, 3-methyl--l butanethiol and 2-butene-I thiol. Volatile thiols are also added to natural gas to serve] as an easily detectable warning in case of leaks. 

This consideration is invalid in two circumstances. The first results from the use of optically active thiols in forming the dithioacetals, which introduces the intrinsic, asymmetric elements of the thiolyl residues. This exception was contrived by Czech workers415 as a scheme to resolve racemic sugar mixtures after converting them into diastereoisomers416 by condensation with (+)-2-methyl-l-butanethiol ... 

MSDS, Safety (MSDS) data for 1-butanethiol, dated 2 March, 2005a. http //ptcl.chem.ox.ac.uk/MSDS/BU/l-butanethiol.html. 

Because a substance combines with oxygen, and because we see carbon in that substance going to CO2, hydrogen going to H2O, and sulfur going to SO2, we classify this reaction as a combustion reaction. The compound C5H11SH is 3-methyl-l-butanethiol, a component of the spray produced by skunks. 

Two major components of a skunk s scent fluid are 3-methyl-l-butanethiol and trans-2-butene-l-thiol. Write structural formulas for each of these compounds. 

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