Why the halogens are deactivating but still ortho para directing?

Halogens are deactivating yet ortho para directing this is because of the fact they withdraw electrons by -I effect(i.e. they deactivate all the positions) but the deactivation at ortho n para positions is opposed by the +R effect of the halide atom.

Is deactivating groups ortho and para directing?

Deactivating groups Halides are ortho, para directing groups but unlike most ortho, para directors, halides mildly deactivate the arene.

Why chlorine is deactivating but ortho para directing?

Chlorine has a lone pair of electrons and hence, shows +R effect. But its electronegativity is comparatively high (around 3.16). So, it has a higher tendency to pull electrons towards itself. This results in ortho-para directing the nature of chlorine in electrophilic aromatic substitution reaction.

How are halogens deactivating?

The halogens deactivate the ring by inductive effect not by the resonance even though they have an unpaired pair of electrons. The unpaired pair of electrons gets donated to the ring, but the inductive effect pulls away the s electrons from the ring by the electronegativity of the halogens.

Which of the following is an ortho para directing but deactivating?

Name an ortho-and para-directing deactivating group. Halogen atom present in benzene ring is ortho, para directing, but deactivating.

Which of the following is deactivating and ortho para director?

Chlorine donate its lone pair to the aromatic ring and hence increase the electron density at ortho and para position. Therefore, chlorine is a deactivating group.

Why are halogens groups deactivating?

Halogens bonded to benzene ring has three lone pairs. These three electron pairs can cause resonance in benzene ring. But, halogens are also highly electronegative and thus they have strong -I effect. So, they are deactivating groups.

Why para product is major and not ortho?

Usually, when an ortho-para directing substituent is present for an electrophilic aromatic replacement reaction on the benzene ring, the para product is the main product except when the COOH group’s hydrogen bonding or ortho effect renders the ortho product a significant one.

Is CL activating or deactivating?

7. Halogens (F, Cl, Br, I) Are Deactivating. Not all groups capable of pi donation are activating groups. For example, halogens (F, Cl, Br, I) tend to be deactivating.

Is NH2 ortho para directing?

– NH2 group of aniline is ortho, para directing in electrophilic substitutions.

Why activators are ortho and para directors?

Why is this? Well, electron-donating groups are activators and ortho-para directors because they stabilize the intermediate cations. The intermediate cations are what is formed between the removal and addition stages.

Which of the following substituents is an ortho and para director and ring deactivating options?

Halogen atom present in benzene ring is ortho, para directing, but deactivating. Why? The substituents which are deactivating but ortho para directing in aromatic substitutions are -NO,-CHO,-F,-Cl,-Br,-CH=CHCHO,-C6H5,-COCl,-NH3 .

Why are halogens deactivating but ortho-para directing?

Ask New Question. Halogens are deactivating yet ortho para directing this is because of the fact they withdraw electrons by -I effect(i.e. they deactivate all the positions) but the deactivation at ortho n para positions is opposed by the +R effect of the halide atom.

Are halogens deactivating or activating groups?

3 Answers 3. Halogens are considered deactivating groups due to the inductive effects of their overwhelming electronegativity withdrawing electrons away from the ring, thus slowing the overall reaction. However, halogens are also able to donate one of their lone pars to the ring through resonance which is characteristic of activating groups.

What is the difference between activating and deactivating groups?

Activating groups (the ones that stabilize the transition state and make the reaction faster) turn out to direct the electrophile to the ortho, para positions, while the deactivating groups put them in the meta position, except for the halogens! Halogens deactivate the aromatic ring, yet they direct the electrophile to the ortho and para positions.

What is the difference between ortho para and ortho N para halogens?

Halogens are deactivating yet ortho para directing this is because of the fact they withdraw electrons by -I effect (i.e. they deactivate all the positions) but the deactivation at ortho n para positions is opposed by the +R effect of the halide atom.