Question

How many compounds among the following compounds show inductive, mesomeric as well as hyperconjugation effects?

Answer 1

Correct Answer: 4

Step 1: Analyze each compound - Compound 1 (−OCH₃ group attached): The −OCH₃ group exhibits both inductive (−I) and mesomeric (+M) effects. However, hyperconjugation is not applicable here. Not included.

• Compound 2 (Alkene with −CH₃): The −CH₃ group shows inductive (+I) and hyperconjugation effects due to the presence of alpha hydrogens. Mesomeric effect is not present. Not included.
• Compound 3 (−NO₂ group): The −NO₂ group exhibits both −I (inductive) and −M (mesomeric) effects but does not participate in hyperconjugation. Not included.
• Compound 4 (−Cl group): The −Cl group shows −I (inductive) and +M (mesomeric) effects, but no hyperconjugation. Not included.
• Compound 5 (−NO₂ group): Similar to Compound 3, exhibits inductive and mesomeric effects but not hyperconjugation. Not included.
• Compound 6 (−CH₃ groups attached to a benzene ring): The −CH₃ groups exhibit inductive (+I) effects and hyperconjugation due to alpha hydrogens. Mesomeric effect is also observed with the aromatic ring. Included.
• Compound 7 (−COCH₃ group): The −COCH₃ group exhibits inductive (−I) and mesomeric (−M) effects. However, no hyperconjugation is observed. Not included.

Step 2: Final Count From the analysis, only 4 compounds exhibit all three effects: inductive, mesomeric, and hyperconjugation.

Final Answer: 4.