The correct order of +m(mesomeric)  effect of N containing functional group on benzene ring with reasoning:-
1. Ph-Nh2
2. Ph-N(ch3)2
3. Ph- Nh-COCH3
4. Ph-N-(COCH3)2

Asked by rohit | 22nd Jul, 2015, 02:19: AM

Expert Answer:

Ph-N(CH3)2 >Ph-NH2 >Ph- NH-COCH3 >Ph-N-(COCH3)2
-N(CH3)2 and -NH2 are electron donating groups and exhibit +R effect or +m effect since they release electrons towards benzene ring through delocalisation.
Ph- NH-COCH3  and Ph-N-(COCH3)2 are electron withdrawing groups.

Answered by Vaibhav Chavan | 22nd Jul, 2015, 11:19: AM

Queries asked on Sunday & after 7pm from Monday to Saturday will be answered after 12pm the next working day.