Question

Match the columns: 

Column - I		Column - II
(A)	\[ \mathrm{CH_2=CH-CH_2Cl} \]	(p)	gem-Dichloride
(B)	\[ \mathrm{CH_2=CHX} \]	(q)	Vinylic halide
(C)	\[ \mathrm{CH_3CHCl_2} \]	(r)	vic-Dichloride
(D)	\[ \mathrm{CH_2ClCH_2Cl} \]	(s)	Allylic halide

• A. \(A \to (r),\ B \to (q),\ C \to (p),\ D \to (s)\)
• B. \(A \to (q),\ B \to (p),\ C \to (s),\ D \to (r)\)
• C. \(A \to (s),\ B \to (q),\ C \to (p),\ D \to (r)\)
• D. \(A \to (r),\ B \to (p),\ C \to (s),\ D \to (q)\)

Hint:

gem-dihalide: \[ \text{Both halogens on same carbon} \] vic-dihalide: \[ \text{Halogens on adjacent carbons} \]

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Organic halogen compounds are classified based on the position of the halogen atom relative to the carbon skeleton and double bonds.
1. Allylic Halides: These are compounds where the halogen atom is bonded to an \( sp^3 \) hybridized carbon atom next to a carbon-carbon double bond (\( C=C \)).
2. Vinylic Halides: These are compounds where the halogen atom is bonded directly to one of the carbon atoms of a carbon-carbon double bond.
3. Geminal (gem-) Dihalides: These contain two halogen atoms attached to the same carbon atom.
4. Vicinal (vic-) Dihalides: These contain two halogen atoms attached to two adjacent carbon atoms.
Step 2: Detailed Explanation:
Let's analyze each entry in Column-I and match it with the descriptions in Column-II:
- (A) \( CH_2 = CH - CH_2Cl \):
In this molecule, the chlorine (\( Cl \)) is attached to a carbon that is adjacent to the double bond. This position is termed the "allylic" position.
Matching: A \( \rightarrow \) (s) Allylic halide.
- (B) \( CH_2 = CHX \):
Here, the halogen \( X \) is directly bonded to a carbon atom that is part of the double bond. This is known as a vinylic attachment.
Matching: B \( \rightarrow \) (q) Vinylic halide.
- (C) \( CH_3CHCl_2 \):
This molecule has two chlorine atoms bonded to the second carbon atom in the chain. Since both halogens are on the {same} carbon, it is a geminal dihalide.
Matching: C \( \rightarrow \) (p) gem-Dichloride.
- (D) \( CH_2ClCH_2Cl \):
In this structure, the two chlorine atoms are on different but {adjacent} carbon atoms. This neighboring arrangement is called vicinal.
Matching: D \( \rightarrow \) (r) vic-Dichloride.
Step 3: Final Answer:
The full set of matches is A-(s), B-(q), C-(p), and D-(r).
Looking at the options:
Option (C) provides this exact combination.
Thus, the correct option is (C).