Question

Which of the following does not show geometrical isomerism?

• A. $1,1\text{-dichloro-}1\text{-pentene}$
• B. $1,3\text{-dichloro-}2\text{-pentene}$
• C. $1,2\text{-dichloro-}1\text{-pentene}$
• D. $1,4\text{-dichloro-}2\text{-pentene}$

Answer 1

The correct option is A $1,1\text{-dichloro-}1\text{-pentene}$

$1,1\text{-dichloro-}1\text{-pentene}$ does not show geometrical isomerism as the one of the double bonded carbons have the same substitutents attached to it.

Hence option (c) is the answer.