225792-97-2Relevant academic research and scientific papers
Synthesis and X-ray crystal structures of the samarium mono(pentamethylcyclopentadienyl) aryloxide complexes (η-C5Me5)Sm(O-2,6-t-Bu2C6H 3)2(THF) and [(η-C5Me5)Sm(O-2,6-i-Pr2C6H 3)3Li(THF)]. Differences in metathesis chemistry of 2,6-di-iso-propylphenoxide.
Butcher, Raymond J.,Clark, David L.,Gordon, John C.,Watkin, John G.
, p. 228 - 237 (1999)
The reaction of SmCl3 with three equivalents of KO-2,6-t-Bu2C6H3 in THF produces the tris(aryloxide) complex Sm(OAr)3(THF) (Ar=2,6-t-Bu2C6H3, 1). Complex 1 undergoes clean metathesis reaction with one equivalent of LiC5Me5 to form the mono(pentamethylcyclopentadienyl) aryloxide derivative (η-C5Me5)Sm(OAr)2(THF) (2). In contrast, an analogous reaction of LiC5Me5 with the 2,6-di-iso-propylphenoxide complex Sm(OAr*)3(THF)2 (Ar=2,6-i-Pr2C6H3, 3) leads to overall addition of the alkali metal reagent, and isolation of the lithium-containing 'ate' complex [(η-C5Me5)Sm(OAr*)(μ-OAr*) 2Li(THF)] (4). Compounds 2 and 4 have been subjected to single-crystal X-ray diffraction studies. Complex 2 features a three-legged piano-stool geometry, with Sm-O distances to the aryloxide ligands of 2.133(6) and 2.188(6) A, and a Sm-O(THF) distance of 2.435(7) A. Complex 4 also exhibits a three-legged piano-stool geometry, with two of the aryloxide oxygen atoms coordinated to a lithium metal center. A THF ligand completes the coordination sphere of the lithium. The Sm-O bond lengths to the lithium-coordinated aryloxide oxygens (2.250(6) and 2.247(5) A) are longer than the distance to the terminal aryloxide (Sm-O=2.144(6) A). The Li-O distances range from 1.876(17) to 1.945(18) A.
