title: Complexes of dibromo(ethylenediamine)-palladium(II) observed from aqueous solutions by electrospray mass spectrometry.
abstract: The dimeric complex of dibromo(ethylenediamine)palladium(II) observed in water was investigated using electrospray mass spectrometry. One microM aqueous solutions of Pd(en)Br2 yielded a variety of previously unreported species. The most abundant ion observed was attributable to the Pd(en)Br2.Pd(en)Br+ dimeric complex at m/z 568.7 (most abundant stable isotopes). The characteristics of the oligomeric complexes were examined using collision-induced dissociation (CID) up to MS6. The most common loss mechanism observed was loss of HBr leaving an unsaturated Pd(II) center. Fragmentation of the ethylenediamine ligand was also observed during CID experiments. Loss of Pd was only observed as the final step in the CID process when other loss mechanisms had been exhausted. A number of calculations were carried out at the B3-LYP/SBKJC[d] level of theory in an attempt to elucidate the structure of the [2M-Br]+ dimer.
authors: Department of Chemistry, The University of Texas at San Antonio, 6900 North Loop 1604 West, 78249-0698, San Antonio, TX, USA. Stephan.Bach@utsa.edu.
authors: Stephan B H
authors: SBH
authors: Bach
authors: Department of Chemistry, The University of Texas at San Antonio, 6900 North Loop 1604 West, 78249-0698, San Antonio, TX, USA.
authors: Tiffanee G
authors: TG
authors: Sepeda
authors: Department of Chemistry, The University of Texas at San Antonio, 6900 North Loop 1604 West, 78249-0698, San Antonio, TX, USA.
authors: Grant N
authors: GN
authors: Merrill
authors: Department of Chemistry, The University of Texas at San Antonio, 6900 North Loop 1604 West, 78249-0698, San Antonio, TX, USA.
authors: Judith A
authors: JA
authors: Walmsley
mesh_terms: D003198:Computer Simulation; D005029:Ethylenediamines / Q000737:chemistry*; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D010165:Palladium / Q000737:chemistry*; D012996:Solutions; D012997:Solvents / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D014867:Water / Q000737:chemistry*
chemical_list: D005029:Ethylenediamines; D012996:Solutions; D012997:Solvents; D014867:Water; D010165:Palladium; C031234:ethylenediamine