2, 4, 6 – Trinitroiodobenzene has three C – N bonds labeled as a, b and c. The correct bond length of the three bonds is -
2, 4, 6 – Trinitroiodobenzene has three C – N bonds labeled as a, b and c. The correct bond length of the three bonds is -
The correct option is C a = b > c
In resonance, only the group which is coplanar with the skeleton can participate in resonance, in case the group is out of plane of the ring (skeleton), it can’t participate in resonance.
The two nitro groups at the ortho positions are forced out of plane (as shown in the image) because of the steric bulk of the large iodine atom.
This makes it mighty inconvenient for the N atoms at the two ortho positions to withdraw electrons (by conjugation) effectively. The planar nitro group does a much better job and as a result, the N at the para position has a decent double bond character. Hence, that C−N bond is shorter than the N atoms involving the nitro groups at the two ortho positions.
Thus a = b > c.
a = b > c
In resonance, only the group which is coplanar with the skeleton can participate in resonance, in case the group is out of plane of the ring (skeleton), it can’t participate in resonance.
The two nitro groups at the ortho positions are forced out of plane (as shown in the image) because of the steric bulk of the large iodine atom.
This makes it mighty inconvenient for the N atoms at the two ortho positions to withdraw electrons (by conjugation) effectively. The planar nitro group does a much better job and as a result, the N at the para position has a decent double bond character. Hence, that C−N bond is shorter than the N atoms involving the nitro groups at the two ortho positions.
Thus a = b > c.
