Question:medium

Hydroboration-oxidation of but-1-ene forms

Show Hint

Hydroboration-oxidation gives anti-Markovnikov alcohol. For terminal alkene, the product is usually a primary alcohol.
Updated On: May 14, 2026
  • Butanal
  • Butanone
  • Butan-1-ol
  • Butan-2-ol
Show Solution

The Correct Option is C

Solution and Explanation

Step 1: Understanding the Concept:
Hydroboration-oxidation is a two-step reaction that converts alkenes into alcohols. It results in the anti-Markovnikov addition of water across the double bond.
Step 2: Key Formula or Approach:
The net result is the addition of \(-\text{H}\) to the more substituted carbon and \(-\text{OH}\) to the less substituted carbon of the double bond.
Step 3: Detailed Explanation:
Reactant: but-1-ene (\(\text{CH}_3\text{-CH}_2\text{-CH=CH}_2\)).
1. Hydroboration: Reaction with \(\text{B}_2\text{H}_6\) / \(\text{THF}\) gives tri-n-butylborane.
2. Oxidation: Reaction with \(\text{H}_2\text{O}_2 / \text{OH}^-\) replaces the Boron with an \(\text{-OH}\) group on the terminal (primary) carbon.
The terminal carbon is less substituted, so \(\text{-OH}\) attaches there:
\[ \text{CH}_3\text{CH}_2\text{CH=CH}_2 \xrightarrow{(i) \text{ B}_2\text{H}_6 / \text{THF}, (ii) \text{ H}_2\text{O}_2 / \text{OH}^-} \text{CH}_3\text{CH}_2\text{CH}_2\text{CH}_2\text{OH} \text{ (Butan-1-ol)} \] Step 4: Final Answer:
The product is Butan-1-ol.
Was this answer helpful?
0