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.

Compounds containing an –SH group attached to a carbon atom are called thiols.

These compounds are more acidic than alcohol because of the larger size of the sulfur atom. They are named by adding a suffix thiol to the parent alkane.

The –SH group in thiols is called the sulfhydryl group and is similar to the hydroxyl group as oxygen and sulfur belong to the same group in the periodic table.

Thiols can be synthesized using base sodium hydrosulfide, a strong base. It is formed from the half neutralization of hydrogen sulfide.

The alkene first undergoes bromination in the presence of an acid or base. The bromide group is substituted with the sulfohydryl group by the action of sodium hydrosulfide, forming a thiol and sodium bromide.

Synthesis of 3-methylbutane-1-thiol-

3-methylbutane-1-thiol is prepared from 3-methyl butane. The bromination of 3-methyl butane is carried out using hydrogen bromide in the presence of peroxide to form 1-bromo-3-methylbutane.

The reaction of 1-bromo-3-methyl butane with sodium hydrosulfide produces 3-methylbutane-1-thiol.

The reaction mechanism can be given as follows:

Synthesis of but-2-ene-1-thiol

But-2-ene-1-thiol s synthesized from but-2-ene or 1,3-butadiene. But-2-ene is reacted with NBS in the presence of light to form 1-bromobut-2-ene, while 1,3-butadiene can be converted to 1-bromobut-2-ene using hydrogen bromide.

1-bromobut-2-ene reacts with sodium hydrosulfide to form but-2-ene-1-thiol.

The reaction can be represented as: