Thread: Meta-Deactivator ?

In an organic Chemistry book on the part of aromatic compounds, it's said"Meta-directing groups are all deactivating..."

What does the"activating and deactivating" mean here....? we know there's some reactions result in meta-product as the the majority, then how come to be deactivating? What a mess! who can help?

If some substituent is activating, it means that aroamtic ring with this substituent reacts faster (and more easily) than benzene itself.

And if some substituent is deactivating it means that aromatic ring with this substituent reacts more slowly than benzene itself.

then how come to say "Meta-directing groups are all deactivating..." "

Metadeactivator - enzyme.

I don't get it,,,,,,,,,

How come that meta-directing %%&*^*&^ are all deactivator?

There are three prefixes used to distinguish the positions of substituents relative to each other on, for example, a benzene ring; they are ortho-, meta-, and para-. If your book says that "meta-directing groups are all deactivating," it may be trying to say that compared to rings with substituents in the ortho- or para- positions, rings with substituents in the meta- position are not active. I've read about this, but I can't remember the exact details, i.e. if a meta- form is indeed less reactive. However, I'm guessing this is what the book is trying to say. As for why specifically the meta- form is deactivating...I've read that, but it's beyond me to explain here...