Why Sulphonation of naphthalene yields different products at low and high temperatures?

Naphthalene undergoes sulphonation at beta position at higher temperature. Beta derivative requires higher activation energy as compared to alpha derivative but once beta derivative formed , is thermodynamically more stable than alpha derivative.

What happens when naphthalene is heated with Sulphuric acid at different temperatures?

In industry naphthalene-monosulfonic acids are produced in a discontinuous process by reacting naphthalene batchwise with sulfuric acid, for the production of the α-acid at a temperature of up to about 50° C., for the preparation of the β-acid at a 160° to 165° C.

What product is obtained by sulphonation of naphthalene?

(2) Naphthalene sulfonation is a reversible reaction, its products are related to external conditions. The main product is α-naphthalene sulfonic acid at low temperature (35-90℃ ), and the same reaction mixture mainly produces β-naphthalene sulfonic acid at high temperature (160-165℃ ).

What is the product when Sulphonation of naphthalene in 165c?

Ans. 1-Naphthalene sulfonic acid. 2-Naphthalene sulfonic acid.

Why Sulphonation is a reversible reaction?

Sulfonation of benzene is a reversible reaction. Sulfur trioxide readily reacts with water to produce sulfuric acid and heat. Therefore, by adding heat to benzenesulfonic acid in diluted aqueous sulfuric acid the reaction is reversed.

Is anthracene a cyclic compound?

Anthracene is a solid polycyclic aromatic hydrocarbon (PAH) of formula C14H10, consisting of three fused benzene rings. Anthracene is used in the production of the red dye alizarin and other dyes.

What happens when naphthalene is treated with Sulphuric acid at 165 Celsius?

Naphthalene reacts with concentrated sulfuric acid to yield naphthalenesulfonic acids.

Is Sulphonation electrophilic substitution?

Nitration and sulfonation of benzene are two examples of electrophilic aromatic substitution. The nitronium ion (NO2+) and sulfur trioxide (SO3) are the electrophiles and individually react with benzene to give nitrobenzene and benzenesulfonic acid respectively.

Why sulfonation of benzene is reversible?

Reverse Sulfonation Sulfonation of benzene is a reversible reaction. Sulfur trioxide readily reacts with water to produce sulfuric acid and heat. Therefore, by adding heat to benzenesulfonic acid in diluted aqueous sulfuric acid the reaction is reversed.

Why 1 Nitronaphthalene is obtained on nitration of naphthalene at room temperature?

Four of these ( 1, 2, 6, and 7) preserve the aromaticity (six π electrons) of the second ring. Nitration at C-2 produces a carbocation that has 6 resonance contributors. So attack at C-1 is favoured, because it forms the most stable intermediate. The major product is 1-nitronaphthalene.

What is the electrophile in Sulphonation of benzene?

The electrophile involved in the sulphonation of benzene is SO3.

What is sulfonation reaction?

Aromatic sulfonation is an organic reaction in which a hydrogen atom on an arene is replaced by a sulfonic acid functional group in an electrophilic aromatic substitution. Aryl sulfonic acids are used as detergents, dye, and drugs.