FT-ICR studies of polypyrazolyl-1-yl borates of europium(II) adducts

• Published in: Journal of alloys and compounds Vol. 323; pp. 147 - 149
• Main Authors: Pires de Matos, A, Freitas, M.A, Marshall, A.G, Marques, N, Carvalho, A, Isolani, P.C, Vicentini, G
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 12.07.2001
• Subjects: Europium; FT-ICR/MS; Polypyrazolylborates; FT-ICR/MS; Europium; Polypyrazolylborates
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/S0925-8388(01)01107-0

In this work we report the synthesis and characterization of europium(II) hydrotris(pyrazol-1-yl)borate complexes, Eu(HBPz 3) 2L 2 (L=bis(pentamethylene)urea, diphenylphosphineamide, 2-azacyclononanone, 2-azacycloheptanone). The characterization of the complexes was accomplished by Fourier transform ion cyclotron resonance mass spectrometry using electrospray ionization. For all the complexes, the Eu(HBPz 3) 2L 2 + ion was observed. To evaluate the relative bond strength of the ligand L to europium polypyrazolylborate, infrared multiphoton dissociation (IRMPD) experiments were performed using a 40-W continuous-wave CO 2 ( λ=10.46 μm) laser aligned on-axis with the ion cloud. The parent ion was dissociated to form the daughter ions, Eu(HBPz 3) 2L + and Eu(HBPz 3) 2 +. The kinetics for unimolecular dissociation showed the relative bond strengths of the different adducts of the europium complex to be: diphenylphosphineamide>2-azacyclononanone≈2-azacycloheptanone. Dissociation experiments could not be made for the adduct with bis(pentamethylene)urea due to the weak bond.