What are ortho para and meta positions?
What are ortho para and meta positions?
The terms ortho, meta, and para are prefixes used in organic chemistry to indicate the position of non-hydrogen substituents on a hydrocarbon ring (benzene derivative). The prefixes derive from Greek words meaning correct/straight, following/after, and similar, respectively.
Is COOH ortho para directing?
For example, a carboxylic acid is a meta director because it experiences resonance, a delocalization of electrons. All of the answer choices in this problem have a lone pair of electrons on the point of contact with the benzene ring and they all are ortho/para directors.
Which is meta directing group?
−CCl3 is a meta directing group. Because chlorine is more electronegative than carbon. So, it pulls the electron density towards itself and acts as a deactivating group on Benzene ring which gives generally meta substituents.
What is an ortho para director?
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.
What is ortho position?
Ortho position in organic chemistry is the one in which there are two same functional groups, tied to a ring of benzene in the positions 1 and 2. The abbreviation o- is used, for example, o-Hydroquinone is 1,2-dihydroxybenzene.
Why methyl group is ortho and para directing?
Answer. Methyl group shows +I effect i.e it is electron donating group soo it increases the electron density at o – p position.So it is o and p directing for electrophilic addition reaction.
Which group is meta directing?
And we know activating groups are ortho and para directing and deactivating groups are meta directing.
Is NH2 meta directing group?
Answer. In NH2 the nitrogen attached to the benzene ring has excess of electron hence it is + R directing group. While in NO2 the nitrogen attached to the benzene ring do not have extra lone pair of electrons hence it is -R effecting group which is meta directing.
Which is the strongest ortho para directing group?
-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.
Why is ch3 ortho para directing?
IN CASE OF TOLUENE the methyl group attached to the ring, increases the electron density at ortho and para positions by resonance without changing anything at the meta position. Thus the attacking reagent directly attacks at the electron rich site , thus the methyl group is ortho directing.