Final answer:
5,5-dimethyl-2-heptyne is the alkyne that will produce a single product upon hydration because it is symmetrical around the triple bond, leading to only one possible ketone. This is in contrast to unsymmetrical alkynes, which could lead to a mixture of ketones. The correct option is option (b).
Step-by-step explanation:
The question pertains to the hydration of alkynes using H₂SO₄ and HgSO₄, which results in the formation of ketones through a process known as oxymercuration-demercuration. The presence of internal or symmetrically substituted alkynes can lead to the formation of a single product. However, with unsymmetrical alkynes, a mixture of ketones could be produced owing to the formation of two possible enol intermediates that can yield different ketones upon tautomerization.
Among the given options, 5,5-dimethyl-2-heptyne is the alkyne that will produce a single product upon hydration. This is because the substituted alkyne is symmetrical around the triple bond, which leads to the formation of only one possible ketone regardless of the side of the alkyne the water adds to.
Examples of other alkynes include:
- 3-methylhexane
- trans-3-heptene
- 4-methyl-1-hexene
- 2-heptyne
- 3,4-dimethyl-1-pentyne
Particularly in the case of hydration of alkene, a water molecule adds across the double bond of an alkene, resulting in an alcohol. However, in the case of the hydration of alkynes, the end product is a ketone rather than an alcohol.