Utility of electrospray mass spectrometry for the characterization of air-sensitive organolanthanides and related species

The utility of electrospray mass spectrometry for the characterization of a ir-sensitive lanthanide complexes has been examined. A wide variety of lant hanide complexes were studied as acetonitrile solutions, including divalent and trivalent compounds, neutral and cationic species, and complexes with cyclopentadienyl as well as alternative ancillary ligands. The spectra are sensitive to the composition of the complex and the oxidation potential of the lanthanide ion. The [(C5Me5)(2)Ln][BPh4] (Ln = Nd, Sm, Y, Tm) complexes form the solvated parent ions [(C5Me5)(2)Ln(MeCN)(x)](+), whereas [Zr-2((O Pr)-Pr-i)(9)]Ln(C5H5) (Ln = Sm, Yb) forms the unsolvated parent ion {[Zr-2( (OPr)-Pr-i)(9)]Ln(C5H5)}(+). [(C5Me5)(2)Ln(MeCN)(x)](+) ions are also obser ved in the spectra of (C5Me5)(2)Ln(C3H5) (Ln = Sm, Y) and (C5Me5)(2)Ln(THF) (x) (Ln = Sm, Eu, Yb). [(C5Me5)Ln(mu -I)(THF)(2)](2) (Ln = Sm, Yb, Eu) and LnI(2)(THF)(2) (La = Sm, Yb, Eu) gave differing sets of ions, depending on the specific metal. The spectra of bimetallic compounds, [(C5Me5)Ln(THF)(x) ](2)(C8H8) (Ln = Sm, Yb), are more complicated.