Lewis acid example sentences

Arenes react with halogens in the presence of a Lewis acid like anhydrous FeCl3, FeBr3 or AlCl3 to yield haloarenes.During chlorination, alkylation and acylation of benzene, anhydrous AlCl3, being a Lewis acid helps in generation of the elctrophile Cl?, R?, RC?O (acylium ion) respectively by combining with the attacking reagent.The tendency to behave as Lewis acid decreases with the increase in the size down the group.Such electron deficient molecules have tendency to accept a pair of electrons to achieve stable electronic configureuration and thus, behave as Lewis acids.