Benzyl complexes of lanthanide(II) and lanthanide(III) metals: Trends and comparisons

Article abstract of DOI:10.1515/znb-2008-0307

A variety of benzyllanthanide complexes have been prepared by the metathesis reaction of benzylpotassium precursors with lanthanide halides. Syntheses and crystal structures for the following complexes are described: [2-Me₂N-α-Me₃Si-benzyl]₂Eu(II) ·(THF)₂ (1-Eu), (2-Me₂N-benzyl)₃Ln(III) (2-Ln with Ln = Nd, Sm, Dy, Ho, Yb), (4-R-C₆H₄CH ₂)₃Ln·(THF)₃ (3-Y: Ln = Y, R = H; 3-La: Ln = La, R = tBu). Complexes of types 1 and 2 are thermally robust on account of a stabilization by a benzylic Me₃Si substituent and/or intramolecular coordination of the Me₂N substituent. Comparison of the crystal structures of these new series of lanthanide complexes shows several similarities and trends. In addition, comparisons with alkali metal and alkaline earth metal benzyl complexes are made.