Which of the following series contains atoms/groups having only -M (mesomeric) effect?

Question

Which of the following series contains atoms/groups having only -M (mesomeric) effect? (A) CO R, O R, COO R (B) Cl , CHO , NH 2 (C) NO 2, CN , SO 3 H (D) OH , N R, S R

Tardigrade Admin · Accepted Answer

C O R,-C O O R ⇒ -M ; -O R ⇒ +M - Cl ,- NH 2 ⇒ +M ; - CHO ⇒ -M - NO 2,- CN ,- SO 3 H ⇒ -M - OH ,- N R2,- S R ⇒ +M

Q. Which of the following series contains atoms/groups having only $- M$ (mesomeric) effect?

$COR, OR, COOR$

$Cl, C H O, N H_{2}$

$N O_{2}, CN, S O_{3} H$

$O H, NR, SR$

$COR, - COOR \Rightarrow - M; - OR \Rightarrow + M$

$- Cl, - N H_{2} \Rightarrow + M; - C H O \Rightarrow - M$

$- N O_{2}, - CN, - S O_{3} H \Rightarrow - M$

$- O H, - N R_{2}, - SR \Rightarrow + M$

Q. Which of the following series contains atoms/groups having only −M (mesomeric) effect?

COR,OR,COOR

Cl,CHO,NH2​

NO2​,CN,SO3​H

OH,NR,SR