Question

difference between ortho and sir effect

Answer 1

Steric Inhibition in resonance is the effect in which a bulky group prevents the resonance of another group attached on a benzene ring.

Now,the bulky group can be present at ortho position with respect to the other group or at the meta position with respect the other group.

Largely, bulky groups at the ortho position show more steric inhibition in resonance .So, we have separately named it as ortho effect.

Large groups like -Si(Me)3 can show meta effect also(steric inhibition in resonance from the meta position).