NEGATIVE-ION CHEMICAL IONIZATION MASS-SPECTRAL (NICIMS) STUDIES - REACTIONS OF METAL SCHIFF-BASE COMPLEXES WITH METHANE - GAS-MIXTURES

The gaseous negative ion reactions of four and five coordinate cobaltII), nickelII), and copperII) Schiff base complexes with gas mixtures have been studied. The gas mixtures contain methane ∼90%) and about 10% of the gases O2 NO, CO, and PF3. Intense parent negative ions were formed by second. ary electron capture processes under moderate chemical ionization conditions. It was observed that the gitseous parent negative ion reacts with the added gas molecule to form the addition product MLX- where X = O2, NO, CO, or PF3, L = Schiff base ligand, and M = NiII) or CoII The abundance of the MLX- secondary ion was greatest in CH4-O2 mixtures. The relative abundance of MLX- for the other gas mixtures varied approximately in the manner MLNO- > MLCO- > MLPF-3. For CuL systems, no MLX- ions were detected. The significant aspects of these results are presented and discussed. Comparisons of the reactivity of these compounds in solution and in the solid state with the gas phase reactions are discussed. © 1979.