Characterization of ionophore-metal complexes by infrared multiphoton photodissociation and collision-activated dissociation in a quadrupole ion trapmass spectrometer

The formation and fragmentation of a series of metal complexes containing p olyether ionophores were studied using electrospray ionization (ESI) method s. Dissociation pathways were analyzed using both collision activated disso ciation (CAD) and infrared multiphoton photodissociation (IRMPD) techniques . A number of structurally diagnostic fragment ions were observed, and in m any cases the same types of pathways were observed for the alkali, transiti on, and alkaline earth metal complexes. The dominant fragmentation pathways included dehydration and cleavage across carbon-carbon bonds to produce ei ther type-F or type-A fragments. Energy-resolved CAD and IRMPD experiments, along with double resonance SWIFT, were performed to evaluate the genealog y of fragmentation pathways.