Synthesis and crystallographic characterization of a dimeric alkynide-bridged organolanthanide: [(C5H5)2ErC.ident.CC(CH3)3]2

Abstract

C5H5)2ErC=CC(CH3)3]2 has been synthesized by the halide-free reaction of [(C5H5)2ErCH3]2 with HC=CC(CH3)3 and characterized by spectroscopic, analytical, and crystallographic methods. The title compound crystallizes from THF in the triclinic space group FT with unit cell dimensions a -3.602 (3) K,b = 8.767 (3) Á, c = 10.216 (5) Á, a = 77.86 (3)°, ß = 84.50 (3)°, 7 = 76.61 (3)°, and Z = 1 (dimer) for Z)c = 1.71 g cm-3. Full-matrix least-squares refinement led to a final R value of 0.065 based on 1321 observed reflections. The two (C5H5)2Er units in the dimer are connected by asymmetrical alkynide bridges with independent Er-C bond lengths of 2.42 (2) and 2.47 (2) Á and Er-C=C angles of 149 (2) and 115 (2)°. Isopiestic studies indicate that this complex is also dimeric in THF solution. [(CH3C5H4)2Yb-C=CC(CH3)3]2 was prepared analogously. Aluminated Metal Alkylidyne Complexes. 2.1 Crystal and Molecular Structure of W(CAl2Me4Cl)(CH3)(PMe3)2(772-C2H4)

A Comparative Study on the Reactivity of Tris‐β‐Diketiminate Ytterbium Complexes: Steric Effect of β‐Diketiminato Ligands

“…[14] Lanthanide analyses were performed by EDTA titration with a xylenol orange indicator and a hexamine buffer. [15] Carbon, hydrogen, and nitrogen analyses were performed by direct combustion with a Carlo-Erba EA-1110 instrument. IR spectra were recorded with a Nicolet-550 FTIR spectrometer as KBr pellets.…”

“…[2][3][4] However, quite different binding modes of Ln-β-diketiminate and bond parameters among the three complexes were observed. (15)°found in the YbL-containing complexes mentioned above. [8] These bond parameters indicate that the coordination environment around the central metal Yb atom in tris-β-diketiminate ytterbium complexes is more crowded than those in the trivalent YbL-containing derivatives and complex 3, with the most bulky β-diketiminato ligands, is the most sterically crowded.…”

Deprotonation of β‐Diketiminate in Sterically Demanding β‐(Diketiminato)lanthanide Complexes: Influence of Lanthanide Metals

“…[10] Lanthanide analyses were performed by ethylenediaminetetraacetic acid (EDTA) titration with a xylenol orange indicator and a hexamine buffer. [11] Carbon, hydrogen, and nitrogen analyses were performed by direct combustion using a CarloErba EA-1110 instrument. The IR spectra were recorded with a Nicolet-550 FTIR spectrometer as KBr pellets.…”

Synthesis of ferrocene‐containing N‐aryloxo β‐ketoiminate lanthanide complexes and polymerization of ε‐caprolactone

“…Lanthanide metal analyses were performed by EDTA titration with a xylenol orange indicator and a hexamine buffer. [13] Carbon, hydrogen and nitrogen analyses were performed by direct combustion with a Carlo-Erba EA-1110 instrument, and crystal or microcrystal samples, but not powder, were used and the samples were transferred into a glovebox. The IR spectra were recorded with a Nicolet-550 FT-IR spectrometer as KBr pellets.…”