Chemistry of dicationic electrophiles: superacid-catalyzed reactions of amino acetals.

Amino acetals are shown to form highly electrophilic systems in Bronsted superacids. It is proposed that amino acetals give dicationic electrophiles, and this proposal is supported by the direct observation of a dication by low-temperature (13)C NMR. When reacted with C(6)H(6) and superacidic CF(3)SO(3)H, amino acetals are shown to provide 1-(3,3-diphenylpropyl)amines and 1-(2,2-diphenylethyl)amines as condensation products in good yields (50-99%).