Question

Predict the site(s) of electrophilic attack on these compounds.

(a)

(b)

Short answer

(a)

(b)

Step-by-step solution

Electrophile

A chemical species which makes a bond with nucleophiles by accepting a pair of electrons is known as an electrophile. It is an electron-deficient species.

Subpart (a) The sites of electrophilic attack on the compound 2-nitrophenol.

In this compound -OH is an ortho-para director as it shows its +I effect more at the ortho/para position.

Here, is a meta director as it shows -M effect at ortho/para position and not at the meta position. Both the functional group’s directions coincide so an electrophilic attack takes place on the sites shown below.

Hence, the positions meta to the group and the position ortho to the OH group are electrophilic in nature.

Subpart (b) The sites of electrophilic attack on the compound 2-methoxy-1,3-dimethylbenzene.

In this compound, the methyl group is a weak ortho-para director and the methoxy group is a strongortho-para director.

Hence, the electrophile attacks the position para to the methoxy group more easily, shown with a star.