`CH_3CH_2CH=CH_2 overset(B_2H_6)underset(H_2O_,H_2O_2,OH^-)rarr Z`
What is Z?

Options

A. `CH_3CH_2CH_2CH_2OH`
B. `CH_3CH_2CH(OH)CH_3`
C. `CH_3CH_2CH_2CHO`
D. `CH_3CH_2CH_2CH_3`

Answer

To solve the given problem, we will go through the hydroboration-oxidation reaction step by step.

### Step 1: Identify the Reactants
The reactant provided is 1-butene, which is represented as CH₃CH₂CH=CH₂. The reagents used are B₂H₆ (diborane), followed by H₂O₂ (hydrogen peroxide) and OH⁻ (hydroxide ion).

### Step 2: Hydroboration
In the hydroboration step, diborane (B₂H₆) reacts with the double bond in 1-butene. The boron atom from B₂H₆ acts as an electrophile and attaches to the less substituted carbon of the double bond (following Markovnikov's rule).

- The double bond (C=C) in 1-butene attacks the boron atom, leading to the formation of a trialkylborane intermediate. In this case, the boron will attach to the terminal carbon (the less substituted carbon), and a carbocation will form on the more substituted carbon.

### Step 3: Formation of the Trialkylborane
The structure after hydroboration can be represented as:
- CH₃-CH₂-CH(BH₂)-CH₃
Here, the boron atom is attached to the terminal carbon, and a positive charge is on the more substituted carbon.

### Step 4: Oxidation
In the oxidation step, we use H₂O₂ and OH⁻. The hydroxide ion (OH⁻) will attack the boron atom, leading to the replacement of the boron with a hydroxyl group (OH).

- The reaction proceeds with the formation of an alkyl alcohol. The boron atom is replaced by a hydroxyl group, and we will have the final product as an alcohol.

### Step 5: Final Product
After the oxidation step, the final product Z will be:
- CH₃-CH₂-CH(OH)-CH₃, which is 2-butanol.

### Conclusion
Thus, the final product Z is **2-butanol**.

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