What are the role of dry ether and AlCl3 in the Friedel -Crafts Alkylation.
AlCl3 is a lewis acid and it which helps in accepting electron from halogen and generate electrophile and dey ether acts as solvent for quickening the reaction.
Does a compound necessarily be a derivative of benzene in order to be an aromatic hydrocarbon?
No ! all the benzene derivatives are aromatic , but to be aromatic it's not necessary for a compound to be derivative of benzene. A compound needs to follow Huckel's rule to be aromatic
You ca take examples like Furan , Thiophene, Pyrrole etc.