The given reactions take place as follows.
1. The replacement of
H-atom in benzene, by alkyl group can be brought about alkyl chloride in presence of anhydrous
AlCl3. Reaction is known as Friedel-Craft's alkylation reaction.
2. In this reaction, benzene reacts to 2 -methyl propane, produce
t-butyl benzene.
3. This can also be carried out by using alkanol and
H2SO4.
4. The reaction I, II and III gives
t-butyl benzene, while IV gives phenyl propanone.