Question

Consider compounds A, B and C with following structural formulae
\(A = CH_3 - CH_2 - CH_2 - CH_2 - CH_2 - OH\)
\(B = CH_2 = CH - CH_2 - CH_2 - CH_3\)
\(C = HO - CH_2 - CH_2 - CH(OH) - CH_3\)
For the conversion of B from A, reagent (D) required is ____ and structural formula of product (E) obtained when C undergoes same reaction using excess reagent (D) is ____.

• A. A
• B. B
• C. C
• D. D

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
We need to identify the reagent \(D\) that converts an alcohol (A) to an alkene (B) and then determine the product (E) when diol (C) is treated with excess of that same reagent.
Step 2: Key Formula or Approach:
Conversion of an alcohol to an alkene is a dehydration reaction, typically carried out using concentrated mineral acids like \(H_2SO_4\) or \(H_3PO_4\) with heat.
Step 3: Detailed Explanation:
1. Reaction \(A \to B\): \(CH_3CH_2CH_2CH_2CH_2OH \xrightarrow{D} CH_3CH_2CH_2CH=CH_2\). This is an elimination reaction. Reagent \(D\) is Conc. \(H_2SO_4\).
2. Reaction \(C \to E\): Compound C is Butane-1,3-diol. Treating it with excess Conc. \(H_2SO_4\) leads to double dehydration.
\[ HO-CH_2-CH_2-CH(OH)-CH_3 \xrightarrow{\text{conc. } H_2SO_4, \Delta} CH_2=CH-CH=CH_2 \]
The resulting product E is Buta-1,3-diene.
Step 4: Final Answer:
Reagent \(D\) is Conc. \(H_2SO_4\) and product \(E\) is \(CH_2=CH-CH=CH_2\).