Question
Which one of the following gives only one monochloro derivative?
A.
$$neo$$ - Pentane
B.
$$n$$ - Hexane
C.
2 - Methylpentane
D.
3 - Methylpentane
Answer :
$$neo$$ - Pentane
Solution :
In $$neo$$ - pentane all the hydrogen are of same type so it can only give one mono-chloro derivative.
\[\underset{neo\text{-Pentane}}{\mathop{C{{H}_{3}}\underset{\begin{smallmatrix}
| \\
\,\,\,\,C{{H}_{3}}
\end{smallmatrix}}{\overset{\begin{smallmatrix}
\,\,\,\,\,C{{H}_{3}} \\
|
\end{smallmatrix}}{\mathop{-C-}}}\,C{{H}_{3}}}}\,\xrightarrow{C{{l}_{2}}}C{{H}_{3}}\underset{\begin{smallmatrix}
| \\
\,\,\,\,C{{H}_{3}}
\end{smallmatrix}}{\overset{\begin{smallmatrix}
\,\,\,\,\,C{{H}_{3}} \\
|
\end{smallmatrix}}{\mathop{-C-}}}\,C{{H}_{3}}Cl\]