# Consequences of ortho effect on resonance

Consider any carboxylic acid with any group at ortho position. According to ortho effect, the resonance of the $$\ce{C=O}$$ with the ring is inhibited.

Is this resonance entirely lost? Or some little amount still exists?

Can resonance be present when the participating orbitals are not in the same plane?

• Well, the "extent of overlap" of the orbitals will decrease but it won't completely vanish, so yes, there will be some resonance stabilisation. – user79161 May 20 '19 at 7:59

If they are off the plane due to steric effect, then resonance wouldn't occur, hence the (-)R effect of - COOH group vanishes and hence "generally" acidity of the respective acid increases.

• Wouldn't occur at all? – user226375 May 20 '19 at 14:13
• Also it took me a minute to realize OFF is not oxygen difluoride. Please don't use CAPS for emphasis (italics or bold is much better). – andselisk May 20 '19 at 14:15