What is the final product of the following reaction sequence?
`(CH_(3))_(3) C-C-=C-H overset((i)dil.H_(2)SO_(4)//HgSO_(4))underset({:(,(ii) NaBH_(4)//"ethanol"),(,"(iii) dil . acid"):})to`

Options

A. `(CH_(3))_(3)C-overset(OH)overset(|)(CHCH_3)`
B. `(CH_(3))_(3)-CH=CH_2`
C. `(CH_(3))_(2)C=C(CH_3)_(2)`
D. `(CH_(3))_(3)C-CH_(2)-CH_(2)OH`

Explanation

To determine the final product of the reaction sequence given in the question, we will break down the steps involved in the reaction process.

### Step 1: Identify the Starting Material
The starting material is `(CH₃)₃C-C≡CH`, which is 3,3-dimethyl-1-butyne.

### Step 2: Reaction with Dilute H₂SO₄ and HgSO₄
When 3,3-dimethyl-1-butyne reacts with dilute sulfuric acid (H₂SO₄) and mercuric sulfate (HgSO₄), it undergoes hydration. The reaction involves the formation of a carbocation.

1. The triple bond (C≡C) is converted into a double bond (C=C) by the addition of H₂O.
2. The more stable secondary carbocation is formed when the double bond is created:
- The reaction proceeds through the formation of a secondary carbocation at the 2-position.
- The product at this stage is 3,3-dimethyl-2-buten-1-ol (with an OH group attached to the more substituted carbon).

### Step 3: Tautomerization
The product undergoes tautomerization, which involves the rearrangement of the structure to form a ketone:
- The alcohol (OH) group can shift to form a carbonyl (C=O) group.
- The resulting product after tautomerization is 3,3-dimethyl-2-butanone.

### Step 4: Reduction with NaBH₄ in Ethanol
Next, the ketone (3,3-dimethyl-2-butanone) is reduced by sodium borohydride (NaBH₄) in ethanol:
- NaBH₄ is a mild reducing agent that selectively reduces ketones to alcohols.
- The final product of this reduction is 3,3-dimethyl-2-butanol.

### Final Product
The final product of the reaction sequence is **3,3-dimethyl-2-butanol**.

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