CATALYZED NITRATION OF AMINES: II. RELATIVE BASICITIES OF SECONDARY AMINES IN ACETIC ACID

Titration of a series of secondary amines with sulphuric or perchloric acid in acetic acid shows that those amines which do not require a chloride catalyst for their nitrations are more weakly proton-accepting than the amines which cannot be nitrated without catalyst. The weak proton-acceptance of imino-bis-acetonitrile which can be nitrated without catalyst is further typified by its tendency to co-ordinate with itself in 16% association in acetic acid solution. By contrast, dibutylamine, which cannot be nitrated without catalyst, is not associated in this medium.