RELATIVE METAL-ION AFFINITIES OF ALKYLAMINES IN THE GAS-PHASE

The relative metal ion (Ni+, Co+, CoCl+) affinities of twelve alkylamines have been estimated using Cooks' kinetic method in a FAB mass spectrometer. The results are compared with proton affinities and with two-ligand dissociation enthalpies. An approximate ordering for the relative metal ion affinities of the amines is given and discussed. The RNH2-Ni+ bond is found to be slightly weaker than RNH2-CoCl+ but stronger than RNH2-Co+. The effective temperature (T) of the metal-bound dimer ions may fall in the range 298 K less-than-or-equal-to T < 400 K.