Answer to Question #309562 in Organic Chemistry for xxxx

Question

predict how CH3 directs an attacking species(such as NO2+, CH3+, Br2 and SO3 to either the 2,3,4 position of the ring during substitution:

Answer 1

There are 2 types of substituents, donor type and accepting type. Donor type: OH, Cl, CH3. Accepting type: NO2, SO3H. Donor type substituents have a lone electrone pair, they donati it to the ring, and electrone density in positions 2 and 4 increase, so substitution undergoes in 2 and 4 positions. Accepting type take electrones from the ring, and the only possible position for substitution is 3.

For example: phenol reacting with NO2+ will form ortho-nitrophenol and para-nitrophenol. Nitrobenzene reacting with SO3 will form only metanitrobenzenesulfonic acid.