The nitroso group is a deactivating group for electrophilic aromatic substitution. ... As the nitrogen is more electronegative than carbon, the nitroso group is electron withdrawing due to induction effect.

Why is nitroso deactivating?

This resonance directs the donated electrons to the ortho/para positions, making the nitroso group ortho/para directing even as the electronegativity of nitrogen and oxygen make it deactivating.

Is nitroso group ortho para directing?

As a result, the nitroso group is a deactivator. However, it has available to donate electron density to the benzene ring during the Wheland intermediate, making it still being an ortho / para director.