On the loss of ammonia from phenylalkyl amines

The molecular ion-minus-ammonia M – NHJ] fragmentation of (3-phenylpropyl) primary amines is a major contributor to the total ion current. This fragmentation occurs to a lesser extent in the lower and higher homologs, (2-phenethy1)- and (4-phenylbuty1)amine. The loss of methylamine and dimethylamine from N-methyl-(3-phenylpropyl)amine and N,N-dimethyl-(3-phenylpropy1)amine respectively is essentially absent. Deuterium labeling has shown that C-3 is the primary source of hydrogen abstracted in the M ? NHJ] fragmentation of (3-pheny1propyl)amine.