question_answer

Sulphonation of phenol at low temperature gives

A)  2-phenol sulphonic acid, a major product

B)  4-phenol sulphonic add, a major product -

C)  Both (a) and (b)

D)  None of the above

Correct Answer: A

Solution :

                Sulphonation of phenol, gives a mixture of ortho and para isomers. If sulphonation is carried out at low temperature, kinetically controlled ortho-isomer is the chief product and if sulphonation is carried out at high temperature, thermodynamically controlled para-isomer is the chief product.