Question

Which of the following group(s) shows $+M$ effect ?

• A. $-N{H}_2$
• B. $-OR$
• C. $-COR$
• D. $-COOH$

Answer 1

Answer: (A), (B)

$-OR$

$+M$ groups increase the electron density on the benzene ring and are called activating groups.
$-N{H}_2$ and $-OR$ both show $+M$ effect whereas $-COR$ and $-COOH$ show $-M$ effect.
$+M$ group increases electron density at ortho/para positions.