dipole moment........

no reply?????????

@gaurav

hmm i seem to have figured out a relation

in fig 1 there is resonance
so the
NO2 is planar in the plane of benzene ring so the dipole moment is high (it cant cancel the dipole moment of CH3 grops attached to other nitrogen as it is in other plane , in other words it hasnt got a cancelling component of dipole moment in the other plane )

in fig 2
however the bulky CH3 groups force NO2 out of the plane of benzene
ring making it in trans like position so the resultant dipole moment decreases

@tnamorp....(u seems to be a fan of Hari Shankar sir....)

it is clear that in 1st compound resonance will be there...whereas it will be absent in 2nd compound.............but i didn't get ur explanation.....