The correct reagent sequence for the following conversion
`CH_(3)-underset(CH_(3))underset(|)overset(CH_(3))overset(|)C-Br to CH_(3)-underset(CH_(3))underset(|)overset(CH_(3))overset(|)C-COOH`, is

Options

A. `overset(KCN)to underset(Delta)overset(H_(3)O^(o+))to`
B. `overset(Mg//"ether")to overset(CO_(2))to overset(H^(o+))to`
C. `overset(Mg//"ether")to overset(Cl-COOH)to`
D. `overset(Mg//"ether")to underset(1.eq.)overset(HCOCl)tounderset(1.eq.)overset(KMnO_(4)//OH^("Θ"))to`

Answer

To convert the compound CH3-C(CH3)2-Br to CH3-C(CH3)2-COOH, we need to follow a series of steps involving specific reagents. Here’s a step-by-step breakdown of the process:

### Step 1: Nucleophilic Substitution
1. **Reagent:** KCN (Potassium cyanide)
- The bromine (Br) atom in the starting compound is a good leaving group. When KCN is added, the Br leaves, forming a tertiary carbocation.
- The cyanide ion (CN-) then attacks the carbocation, resulting in the formation of CH3-C(CH3)2-CN.

### Step 2: Hydrolysis of Nitrile
2. **Reagent:** H2O (Water) in acidic medium
- The nitrile (CN) undergoes hydrolysis in the presence of water and an acid (like HCl) to convert it into a carboxylic acid.
- The CN group is converted into a carboxylic acid (COOH) through the formation of an intermediate amide, which is then hydrolyzed to yield CH3-C(CH3)2-COOH.

### Summary of Reagents
- The correct sequence of reagents for the conversion is:
1. KCN (to form the nitrile)
2. H2O (in acidic medium for hydrolysis)

### Final Product
- The final product is CH3-C(CH3)2-COOH, which is a carboxylic acid.