In the given reaction
`CH_3-CH_2-C-=C-Hunderset((ii)H_2O_2//Ooverset(Theta)H)overset((i)BH_3)rarr(X)`, (X)will be

Options

A. Butanal
B. Butanone
C. 2 - butanol
D. 1 - butanol

Answer

To solve the given reaction step by step, we will analyze the hydroboration-oxidation process involving the alkyne \( CH_3-CH_2-C \equiv C-H \).

### Step 1: Identify the starting material
The starting material is 1-butyne, which has the structure:
\[ CH_3-CH_2-C \equiv C-H \]

### Step 2: Addition of BH3
In the hydroboration step, we add borane (BH3) to the alkyne. The addition occurs according to the anti-Markovnikov rule, where the hydrogen atom from BH3 will add to the carbon with fewer hydrogen atoms (the terminal carbon), and the boron will add to the carbon with more hydrogen atoms.

After the first addition of BH3, we get:
\[ CH_3-CH_2-CH=CH-BH_2 \]

### Step 3: Further addition of BH3
Since we have a terminal alkyne, we will need to add two more moles of BH3 to fully react with the alkyne. The reaction will continue until all three moles of BH3 have reacted with the three moles of the alkyne. After the complete addition, we will have:
\[ CH_3-CH_2-CH=CH-BH_2 \text{ (from the first addition)} \]
\[ + \text{(two more moles of BH3)} \]
\[ = CH_3-CH_2-CH(BH_2)-CH(BH_2) \]

### Step 4: Oxidation with H2O2 and OH-
Next, we perform the oxidation step by adding hydrogen peroxide (H2O2) and hydroxide ions (OH-). This will convert the boron groups into hydroxyl groups (-OH) through a series of reactions.

The product after the oxidation will be:
\[ CH_3-CH_2-CH=CH-OH \]
This is the enol form.

### Step 5: Tautomerization to form the final product
The enol can undergo tautomerization to form a ketone. The double bond shifts, and the hydroxyl group moves to the adjacent carbon, resulting in:
\[ CH_3-CH_2-CH_2-CO \]
This compound is butan-2-one (or butan-2-ol in its alcohol form).

### Final Answer
Thus, the final product \( (X) \) formed from the reaction is:
\[ \text{Butan-2-ol} \]

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