Does phenol need a catalyst to react with bromine?

Does phenol need a catalyst to react with bromine?

For example, as you will find below, phenol will react with a solution of bromine in water (bromine water) in the cold and in the absence of any catalyst. It also reacts with dilute nitric acid, whereas benzene itself needs a nitrating mixture of concentrated nitric acid and concentrated sulphuric acid.

Why is bromination of phenol not required catalyst?

In phenols, the lone pair from the oxygen delocalises into the π electrons, increasing the electron density in the ring and making it more nucleophilic. This means that it is more able to polarise a molecule and produce an electrophile meaning that a catalyst isn’t required.

Which reagent is used in bromination of phenol?

So the reaction of the bromination of phenol by bromine water is the following: So the formation of $ 2,4,6 $ tribromophenol takes place with the help of the reagent called bromine water.

Which chemicals can react with Phenol?

Phenol is a good nucleophile, meaning it likes to donate electrons, and therefore can form a chemical bond in reactions. Phenol can react with acetyl chloride and acetic anhydride to form esters. Esters are when one or more OH (hydroxyl) groups are replaced by an O-alkyl (alkoxy) group.

What happens when Phenol reacts with Naoh?

Phenol reacts with sodium hydroxide solution to give a colourless solution containing sodium phenoxide. In this reaction, the hydrogen ion has been removed by the strongly basic hydroxide ion in the sodium hydroxide solution.

How does FeBr3 act as a catalyst?

When benzene reacts with bromine under harsh conditions—liquid bromine, no solvent, and the Lewis acid FeBr3 as a catalyst—a reaction occurs in which one bromine is substituted for a ring hydrogen. Alkenes react spontaneously with bromine and chlorine, even in dilute solution, to give addition products.

How is aspirin converted to phenol?

Therefore, we can convert phenol to aspirin by treating phenol with sodium hydroxide and carbon dioxide in an acidic medium. Then treated the product salicylic acid with acetic anhydride. Note:The molecular formula of aspirin is C9H8O4 C 9 H 8 O 4 .

What is bromination of phenol?

We know that the reaction of phenol and water with bromine is known as bromination of phenol. It is so because in aqueous medium phenol ionizes to form peroxide ion. Due to the presence of negative ions the ring gets highly activated and tri substitution occurs and the formation of 2,4,6 – tribromophenol takes place.

What happens when phenol reacts with Naoh?

What happens when phenol is mixed with bromine?

The reaction of phenol with bromine is known as bromination of phenol. Solvent has great influence on the reaction.In different solvents, different products are obtained.The action of bromine on phenol can be explained as. Phenol reacts with bromine water to give 2,4,6-tribromophenol.

How does bromine react with benzene in halogenation?

The presence of Br + compared to Br 2 alone is a much better electrophille that can then react with benzene. As the bromine has now become more electrophillic after activation of a catalyst, an electrophillic attack by the benzene occurs at the terminal bromine of Br-Br-AlBr 3. This allows the other bromine atom to leave with

Why do you need a catalyst for bromination?

Bromination is acheived with the help of AlBr 3 (Lewis acid catalysts) as it polarizes the Br-Br bond. The polarization causes polarization causes the bromine atoms within the Br-Br bond to become more electrophillic.

How is the activating power of phenol reduced?

For example, the bromination of phenol leads to 2,4,6-tribromophenol even in the absence of a Lewis acid (Fig. 4). The activating power of the phenolic group can be decreased by converting the phenol to an ester which can be removed by hydrolysis once the electrophilic sub-stitution reaction has been carried out (Fig. 5).

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