The reactivity of N-alkyl-2-bromopyridinium ions (alkyl= Me, Et, n-C12H25, n-Cl4HB, n- C16H3,) toward OH-is affected by cationic micelles of alkyltrimethylammonium chloride or bromide (alkyl= n-C14Hzs, n-C16H33) which inhibit reactions of the methyl and ethyl substrates and catalyze reactions of the more hydrophobic derivatives. These results are understandable, qualitatively, in terms of the distribution of both reactants between the ...