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There are 3 possible places for the nitro group to attach: An ortho, meta, or para position. To understand the stability of the carbocation, we need to look at the resonance structures for a given attack and see what the results are.
The first resonance structure of the ortho attack results in a positive charge on the carbon with the hydroxyl group. This happens to be the most stable of the 3 resonance structures for an ortho attack because the two negative electron pairs in the oxygen act to stabilize the positive charge on the carbon. The other two resonance forms leave a carbon with a hydrogen attached, to hold the positive charge. Hydrogen can do nothing to stabilize the charge and thus, these are less stable forms.
In the para attack situation, notice that the second resonance form also puts a positive charge on the carbon with the hydroxyl group. This provides for stability just as it does in the case of an ortho attack and thus, the middle resonance form is very stable.
Finally, in the meta attack situation, all of the resonance forms result in a positive charge on a carbon with only a hydrogen attached. None of these is stable, and thus, meta attack with a hydroxyl group attached, is a very small percentage of the product.
So the electron pairs in the oxygen act to stabilize the ortho and para attacks.
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Activating and deactivating group of Ortho para and meta director groups Explain?
You can either deactivate or activate the group of Ortho para and Meta director groups depending with your preference.
Ortho - hydroxyacetophenone vs para - hydroxyacetophenone polarity?
para is more polar than the ortho
What is ortho meta and para in benzene?
ortho-para in benzene is meaningless these positions are for monosubstituted benzene. Meta is positions 3 and 5. Ortho is position 2 and 6 with relation to already attached group, para is 4 (opposite) to attached group.
Why halogens that is deactivate group attack to ortho and para position?
Because of mesomeric effect, the electron density on the ortho and para positions for the aromatic ring is more.
Why nitroso in nitrosobenzene deactivating yet ortho para directing?
NO-group acts exactly as halogens because of long pair on nitrogen. This pair stabilizes ortho-para intermediates.
Activating and deactivating group of Ortho para and meta director groups Explain?
You can either deactivate or activate the group of Ortho para and Meta director groups depending with your preference.
Why do not aliphatic amines give coupling reaction?
because aliphatic amine is a weak electrophile. second because the coupling reaction occur at ortho and para position only,while in aliphatic,there is no ortho or para position
Ortho - hydroxyacetophenone vs para - hydroxyacetophenone polarity?
para is more polar than the ortho
What is para and ortho hydrogen?
A molecule of diatomic hydrogen (hydrogen gas) contains two hydrogen atoms. The nucleus of each aton (a protron) is spinning. Depending upon the direction of the spin of the two nuclei, the hydrogens are of two types: ortho or para. Ortho-hydrogen molecules are those in which the spins of both the nuclei are in the same direction. Para-hydrogen is when the spins of both the nuclei are in the opposite directions. Ordinary hydrogen gas is an equilibrium mixture of ortho and para hydrogen. The amount of ortho- and para-hydrogen varies with temperature. At 0°K, hydrogen contains mainly para-hydrogen which is more stable. At the temperature of liquid of air, the ratio of ortho- and para-hydrogen is 1 : 1. At the room temperature, the ratio of ortho- to para-hydrogen is at its maximum of 3 : 1. Even at very high temperatures, the ratio of ortho- to para-hydrogen can never be more than 3 : 1. So, it is possible to get pure para hydrogen by cooling ordinary hydrogen gas to a very low temperature (close to 20 K) but it is never possible to get a sample of hydrogen containing more than 75% of ortho hydrogen.
Why methyl attached to benzene is ortho-para director group?
This group attached to benzene ring acts as the ortho-para directing group due to Hyperconjugation.
What is ortho meta and para in benzene?
ortho-para in benzene is meaningless these positions are for monosubstituted benzene. Meta is positions 3 and 5. Ortho is position 2 and 6 with relation to already attached group, para is 4 (opposite) to attached group.
Why halogens that is deactivate group attack to ortho and para position?
Because of mesomeric effect, the electron density on the ortho and para positions for the aromatic ring is more.
What are the examples of Ortho and para directing group and mata directing group?
Electrophilic Aromatic Substitution is an example of Ortho and para directing group and meta directing group.
What is the ortho-peradirective nature?
I think you're asking about ortho-para directors. o,p directors are groups bonded to a benzene ring that direct additional groups in electrophilic aromatic substitution reactions to attach to the ortho and para positions of the benzene ring. Ortho is the position next to the group and para is the position across from the group on the benzene ring. o,p directors are electron donating groups such as methoxy groups. These groups stabilize the positive charge created in the intermediate when the electrophile adds to the ortho and para positions. o,p directors do not, however, stabilize the positive charge when the electrophile adds to the meta position and therefore only allow addition to the ortho and para positions (thus the name ortho-para director).
Why nitroso in nitrosobenzene deactivating yet ortho para directing?
NO-group acts exactly as halogens because of long pair on nitrogen. This pair stabilizes ortho-para intermediates.
What are the differences between ortho hydrogen and para hydrogen?
Positioning around a benzene ring relative to the major functional group. Para is opposite, ortho is next to, meta is in between.
Why nitro group is formed on ortho and para position?
orientation of incoming Nitro group is destined by already present group on benzene ring . if already present group is electron donating group, it will promote electron density at ortho and para position and , therefore, nitro group is formed on ortho and para position.
