Site of protonation and bifunctional group interactions in α,ω-hydroxyalkylamines

Chemical ionization mass spectrometry and mass analyzed ion kinetic energy spectrometry in conjunction with collision induced dissociation are used to study the fragmentation behavior of a series of α,ω-hydroxyalkylamines. The difference between the ionic population present at equilibrium in the source, and that which is sampled under nonequilibrium conditions, is revealed in the striking differences observed in product distributions in the chemical ionization mass spectra and the mass analyzed ion kinetic energy spectra. The major fragmentations in the mass analyzed ion kinetic energy spectra, loss of NH₃ and H₂O, show large variations in intensity as a function of the chain length between the hydroxy and amino functionalities. These results are rationalized through analysis of the relevant thermochemical data.