Acid addition salts of imidazolidinones are provided as catalysts for transforming a functional group within a first reactant by reaction with a second reactant. Exemplary first reactants are α,β-unsaturated carbonyl compounds such as α,β-unsaturated ketones and α,β-unsaturated aldehydes. Chiral imidazolidinone salts can be used to catalyze enantioselective reactions, such that a chiral product is obtained from a chiral or achiral starting material in enantiomerically pure form.