Which is a strong ortho director?

-The hydroxyl group is the strongest ortho para directing group as hydroxyl group is electron releasing group and it increases the electron density in the benzene ring through resonance and activates the ring towards electrophilic substitution.

How do you choose ortho meta para?

If the relative yield of the ortho product and that of the para product are higher than that of the meta product, the substituent on the benzene ring in the monosubstituted benzene is called an ortho, para directing group. If the opposite is observed, the substituent is called a meta directing group.

What are ortho and para directors?

Ortho/para director: In electrophilic aromatic substitution, a substituent that favors electrophilic attack ortho or para to the substituent. Most ortho/para directors are also activators, except for the halogens, which are deactivators.

Why are alkyl groups ortho-para directors?

Groups with an oxygen or nitrogen attached to the aromatic ring are ortho and para directors since the O or N can push electrons into the ring, making the ortho and para positions more reactive and stabilizing the arenium ion that forms.

Why is ortho and para more stable than meta?

Note how the carbocations for the “ortho” and “para” cases are the most stable (since every atom has a full octet). This means they’ll be faster to form than the “meta” carbocation, which is less stable. That’s why the major products are ortho and para .

What does ortho mean in inorganic chemistry?

In inorganic chemistry, the prefixes meta- and ortho- are used to designate types of acids that differ in the number of hydroxyl groups (ortho- means the greatest number, and meta-, the smallest)—for example, orthophosphoric acid, H3PO4 and meta-phosphoric acid, HPO3.

Why are halogens ortho para directors?

Halogens are very electronegative. This means that inductively they are electron withdrawing. However, because of their ability to donate a lone pair of electrons in resonance forms, they are activators and ortho/para directing. Because they are electron withdrawing, halogens are very weak activators.