ELECTROSPRAY-IONIZATION MASS-SPECTRAL INVESTIGATIONS ON MULTINUCLEAR COMPLEXES OF AN AZACRYPTAND

The electrospray ionization (ES) mass spectrum of a trisodium azacrypt ate derived from a template reaction of sodium 2,6-diformyl-4-methylph enolate (sdmp) with 2,2',2''-triaminoethylamine (tren) was investigate d and compared with those by fast atom bombardment (FAB), atmospheric pressure chemical ionization (APCI) and electronic ionization (EI) met hods. Dinuclear transition metal complexes of this hexaimine macrobicy clic ligand obtained by transmetallation were also studied by ES mass spectra. An [M(2)L](+) species has been observed for divalent metal co mplexes, and an [MLH](+) species for a trivalent metal complex. The po ssible mechanism of the fragmentation process is discussed.