Question

Which of the following isomeric dienes is chiral?
A) 2,3-pentadiene
B) 3-methyl-1,2-butadiene
C) 2-methyl-1,3-butadiene
D) none, all are achiral
Please answer fast and clearly with explanations !
Irrelevant answers will be reported !

Answer 1

Answer:

a) 2 , 3-pentadiene✔

because of double carbon - carbon bond .

Answer 2

OPTION (A) IS CORRECT.

A) 2, 3 - PENTADIENE

Explanation:

• A chiral carbon molecule contains 4 different substituents attached to it.
• A molecule which do not have 4 different groups but still it is chiral, such species are known as Allenes.
• Allenes are cumulative dienes, which contain consecutive double bonds, they are chiral as one end of the chain is in the plane and other is outside the plane.
• In it a carbon atom contains two double bonds.
• 2,3 -pentadiene is a cumulative diene so it will be chiral.
• It has non-superimposable mirror images.
• Therefore, option (A) 2,3-pentadiene is correct.