What is the final product of the reaction ?
`(CH-)(3) HC = C (CH_(3)) CH_(2)CH_(3)underset((ii)H_(2)O_(2)//bar(O)H)overset((i)BH_(3)//THF) to underset(CH_(2)Cl_(2))overset(P"CC")tounderset((ii)H_(3)O^(+))overset((i)CH_(3)MgBr) to`

Options

A. 2,3 - dimethyl - 3-- pentanol
B. 2,4 - dimethyl - 3 - pentanol
C. 2,3 - dimethyl - 2- pentanol
D. 2,2 - dimethyl - 3- pentanol

Explanation

To determine the final product of the given reaction, we will follow the steps outlined in the video transcript. Let's break down the reaction step by step:

### Step 1: Hydroboration with BH3/THF
The initial compound is an alkene:
\[ \text{(CH}_3\text{)}_2\text{C}=\text{C(CH}_3)\text{CH}_2\text{CH}_3 \]

When this alkene reacts with BH3 in THF, it undergoes hydroboration. According to the anti-Markovnikov's rule, the hydrogen from BH3 will attach to the more substituted carbon atom, and the hydroxyl group (OH) will be added to the less substituted carbon after subsequent oxidation.

**Product after hydroboration:**
\[ \text{(CH}_3\text{)}_2\text{C(OH)}\text{CH}_2\text{CH}_3 \]
This can be represented as:
\[ \text{CH}_3\text{C(OH)}\text{CH}_2\text{C(CH}_3)\text{CH}_3 \]

### Step 2: Oxidation with PCC
Next, the product from the hydroboration step is treated with PCC (Pyridinium chlorochromate), which is an oxidizing agent. This will convert the alcohol (OH) group into a carbonyl group (C=O), resulting in a ketone.

**Product after oxidation:**
\[ \text{(CH}_3\text{)}_2\text{C=O}\text{CH}_2\text{CH}_3 \]
This can be represented as:
\[ \text{CH}_3\text{C(=O)}\text{C(CH}_3)\text{CH}_2\text{CH}_3 \]

### Step 3: Reaction with Grignard Reagent (CH3MgBr)
The ketone formed will then react with the Grignard reagent, CH3MgBr. The nucleophilic carbon from the Grignard reagent will attack the carbonyl carbon, leading to the formation of a tertiary alcohol after hydrolysis.

**Product after Grignard reaction:**
The structure after the Grignard reaction and subsequent hydrolysis will be:
\[ \text{(CH}_3\text{)}_2\text{C(OH)}\text{CH}_2\text{CH}_3 \]
This can be represented as:
\[ \text{CH}_3\text{C(OH)}\text{C(CH}_3)\text{CH}_2\text{CH}_3 \]

### Final Product
The final product of the reaction is:
\[ \text{2,3-dimethyl-3-pentanol} \]

### Summary
The final product of the reaction is **2,3-dimethyl-3-pentanol**.

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