Question

Arrange the following alkenes in the decreasing order of stability:
 
Choose the correct answer from the options given below: 
 

• A. III $>$ II $>$ I $>$ IV
• B. I $>$ III $>$ II $>$ IV
• C. III $>$ I $>$ II $>$ IV
• D. I $>$ III $>$ IV $>$ II

Hint:

Alkene stability order: tetra $>$ tri $>$ trans-disubstituted $>$ cis-disubstituted.

Answer 1

The Correct Option is B

The stability of alkenes is influenced by several factors, including the degree of substitution and hyperconjugation. Alkenes with more substituted carbon atoms tend to be more stable due to hyperconjugation and the inductive effect.

Let's analyze each alkene:

1. Structure I: This is a tetrasubstituted alkene. It has four alkyl groups attached to the double-bonded carbons, which provides high stability.
2. Structure II: This is a disubstituted alkene (cis). It has two hydrogen atoms and two alkyl groups attached, offering moderate stability.
3. Structure III: This is a trisubstituted alkene. It has three alkyl groups attached, making it more stable than a disubstituted alkene.
4. Structure IV: This is a disubstituted alkene (trans). Although trans alkenes are generally more stable than cis, the presence of fewer substituents than structure III makes it less stable overall.

Based on the degree of substitution and stability factors, the order of stability is:

\(I > III > II > IV\)

Therefore, the correct answer is: I > III > II > IV