Mass spectrometry of metal complexes of bis-quinolizidine alkaloids: electron ionization and fast atom bombardment mass spectral study of copper(II) (-)-sparteine and (-)-alpha- isosparteine complexes.

The electron ionization (EI) and fast atom bombardment (FAB) mass spectral fragmentations of ten copper(II) dichloride (dibromide, diformate, diacetate and dithiocyanate) complexes of (-)-sparteine and (-)-alpha-isosparteine were investigated. Fragmentation pathways, elucidation of which was assisted by accurate mass measurements and metastable transitions (EI-MS), as well as FAB/collision-induced dissociation (CID) mass spectral measurements are discussed. The data obtained create the basis for the differentiation of the ligand (sparteine or alpha-isosparteine) in the investigated complexes. The comparison of the results with those obtained previously for corresponding zinc(II) complexes forms the basis for the differentiation of metals in these compounds. The results show that both EI-MS and FAB-MS are very useful tools for the differentiation of ligands, as well as metals in the series of Zn(II) and Cu(II) dichloride (dibromide, diacetate, diformate, dithioacetate) complexes of (-)-sparteine and (-)-alpha-isosparteine.