Illustrated Glossary of Organic Chemistry

Acid promoted: A reaction that requires an acid to occur, but is not catalytic in acid (i.e., the acid is not regenerated in the reaction mechanism).

Electrophilic addition of HCl to an alkene is promoted by acid (HCl) but not catalyzed by acid because the acid is not regenerated in the reaction mechanism.


Electrophilic addition of water to an alkene is catalyzed by acid (H3O+) because the acid used in the first mechanism step is regenerated at the end of the mechanism.