Types of deamination reactions

The transformation of amines over acidic catalysts is more complicated than that of other compounds which can undergo elimination. Like alcohols, amines form either an olefin or a higher substituted amine (the formal counterpart of an ether). With trivalent nitrogen, the reaction scheme includes more compounds than divalent oxygen allows, viz. 

Similarly, like secondary and tertiary alcohols, amines with the alkyl groups branched ona-carbon atoms (i.e. containingthe grouping R R2CH— 

N— and R R2R3C—N—) tend more to olefin formation than to disproportionate. 

TV-Alkylidenalkylamines were found in the reaction products of the transformation of 1-butylamine [147,148], cyclohexylamine and isopropylamine [149] on alumina, and were probably formed by the dehydrogenation of the primary amine to an imine, followed by its condensation with a second molecule of the amine [148], rather than by the dehydrogenation of the dialkylamine [147], The TV-alkylidenalkylamines R=N—R decompose to an olefin and an imine a cyclic process has been postulated [148] which explains the increases in reactivity of amines with secondary alkyls. Also butyronitrile has been detected in appreciable amounts in the reaction products of 1-butylamine on alumina at 500° C [147], 

Much less information is available on the deamination and related reactions over solid catalysts than on some other elimination reactions but it suffices for comprehension of the general features. 

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