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10/04/2019

What are activators and deactivators?

What are activators and deactivators?

What are activators and deactivators? In short, the groups that donate electron density to the ring and make it electron-rich are activators. The ones that withdraw the electron density are deactivators.

What are activators and deactivators in organic chemistry?

Generally speaking, electron donators / activators have a lone pair of electrons or an electron density that “pushes” into the benzene. Electron withdrawers / deactivators have a positive charge on the substituent or a very electronegative atom attached to it, which “pulls” electrons out of the benzene.

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.

What are activating and deactivating groups with examples?

As we just saw, CH3 is a perfect example of an activating group; when we substitute a hydrogen on benzene for CH3, the rate of nitration is increased. A deactivating group, on the other hand, decreases the rate of an electrophilic aromatic substitution reaction, relative to hydrogen.

What is meant by deactivating groups?

In organic chemistry, a deactivating group is a functional group attached to a benzene molecule that removes electron density from the benzene ring, making electrophilic aromatic substitution reactions slower and more complex relative to benzene.

What is ortho meta and para in chemistry?

Updated October 02, 2019. 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.

What is activation organic chemistry?

Activation, in chemistry and biology, is the process whereby something is prepared or excited for a subsequent reaction.

What makes an activating group?

If electrophilic aromatic substitution of a monosubstituted benzene is faster than that of benzene under identical conditions, the substituent in the monosubstituted benzene is called an activating group. Thus, the methyl group is an activating group. All activating groups are electron-donating groups.

How are activators related to electrophilic aromatic substitution?

Activators increase the rate of electrophilic aromatic substitution and deactivators decrease it: There are two factors that determine if the group is electron donating or withdrawing. These factors are the inductive and the resonance effects.

Which is an activator and which is a deactivator?

In short, the groups that donate electron density to the ring and make it electron-rich are activators. The ones that withdraw the electron density are deactivators. Activators increase the rate of electrophilic aromatic substitution and deactivators decrease it: There are two factors that determine if the group is electron donating or withdrawing.

Do you think – Oh would be activating or deactivating?

Do you think –OH would be activating (increase the rate) or deactivating (decrease the rate) for electrophilic aromatic substitution (such as nitration)? Guessing is OK! Based on what we just said, it’s fully understandable if you said, “deactivating”.

Which is an example of a deactivating group?

Examples are NO 2, carbonyl groups (C=O), sulfonyl, cyano (CN) among others. These groups are universally deactivating, slowing the rate of electrophilic aromatic substitution.