215817-06-4Relevant academic research and scientific papers
Synthesis, structure, and reactivity of cyclopentadienyl-free trimethylsilylmethyl yttrium di-tert-butylphenoxide complexes
Evans, William J.,Broomhall-Dillard, Randy N.R.,Ziller, Joseph W.
, p. 89 - 97 (1998)
The chemistry of yttrium with the trimethylsilylmethyl/2,6-di-tert-butyl-phenoxide ligand combination has been examined. The anionic dialkyl-diaryloxide complexes, {(Me3SiCH2)2Ln(OC6H3 tBu2-2,6)2}- (Ln=Y, Lu), were prepared and their reactivity and that of the neutral dialkyl-aryloxide complex (Me3SiCH2)2Y(OC6H3 tBu2-2,6)(THF)2, 1, has been studied and compared with cyclopentadienyl-containing organolanthanide complexes. {(Me3SiCH2)2Y(OC6H3 tBu2-2,6)2}{[(THF)3Li] 2Cl}, 2, was prepared from the reaction of YCl3 with two equivalents of LiCH2SiMe3 and two equivalents of LiOC6H3tBu2-2,6 and crystallized with an unusual cation which can be viewed as a LiCl adduct of [Li(THF)x]+. [(Me3SiCH2)2Lu(OC6H3 tBu2-2,6)2][Li(THF)4](THF) 2, 3, was prepared analogously and crystallized with a conventional cation. Both 2 and 3 have distorted tetrahedral coordination geometries around the metals. Ring-opening polymerization of ε-caprolactone was observed for 1-3, but only complex 1 was found to polymerize ethylene. NMR and mass spectroscopic analyses show that the more reactive complex 1 also exhibits metallation reactivity with pyridine, toluene, phenylacetylene, CH3CN, Me2CHCN, PhCN, and PhCH2CN and insertion chemistry with Me3CNC, CO, CO2, PhNCO, and PhNCS. However, isolation of the organometallic products has been difficult due to the complexity of the reaction mixtures.
