Editing Lewis acids and bases (section)

===Applications of Lewis acids===
A typical example of a Lewis acid in action is in the [[Friedel–Crafts alkylation]] reaction.<ref name=March>March, J. “Advanced Organic Chemistry” 4th Ed.  J. Wiley and Sons, 1992: New York.  {{ISBN|0-471-60180-2}}.{{page needed|date=September 2021}}</ref> The key step is the acceptance by AlCl<sub>3</sub> of a chloride ion lone-pair, forming {{chem2|AlCl4-}} and creating the strongly acidic, that is, [[electrophilic]], carbonium ion.
:RCl +AlCl<sub>3</sub> → R<sup>+</sup> + {{chem2|AlCl4-}}