354111-82-3Relevant academic research and scientific papers
Rare earth complexes of bulky 2,6-diphenylphenolates containing additional, potentially buttressing 3,5-substituents
Deacon, Glen B.,Fanwick, Phillip E.,Gitlits, Alex,Rothwell, Ian P.,Skelton, Brian W.,White, Allan H.
, p. 1505 - 1514 (2001)
The rare earth aryloxide complexes, [Yb(OArtBu)3-(THF)]·THF, [Sc(OArtBu)3(THF)]·THF, [Yb(OArMe)3(THF)], and [Sm(OArPh)3(THF)2] (OArR = 2,6-diphenyl-3,5-di-R-phenolate), have been prepared by redox transmetallation/ligand exchange between the rare earth metal, bis(pentafluorophenyl) mercury, and HOArR in tetrahydrofuran. This reaction also provided [Yb(OArPh)3(DME)]·3/2THF by incorporation of adventitious 1,2-dimethoxyethane. A similar reaction between Yb metal, diphenylmercury, and HOArMe gave [Yb(OArMe)2(THF)3]. The homoleptic complexes [Yb(OArPh)3] and [Sc(OArH)3] have been prepared by direct reaction of the rare earth element with HOArR in a sealed tube in the presence of mercury at elevated temperatures (200-250 °C) and the latter was converted into [Sc(OArH)3(THF)] by treatment with THF. X-ray crystal structure determinations of [Yb(OArtBu)3(THF)]·THF, [Sc(OArtBu)3(THF)]·THF, and [Yb(OArMe)3(THF)] show the complexes to be monomeric and four coordinate with a trigonal pyramidal stereochemistry. These structures provide clear evidence that groups meta to the phenolate donor can modify the coordination behaviour of the 2,6-diphenylphenolate ligand. In [Yb(OArPh)3(DME)]·3/2THF a distorted square pyramidal stereochemistry is observed. The divalent complex [Yb(OArMe)2(THF)3] exhibits a distorted trigonal bipyramidal arrangement of the oxygen donor atoms with apical THF ligands. The homoleptic scandium 2,6-diphenylphenolate has three oxygen atoms in a triangular array with additional π-η1Ph···Sc interactions above and below the ScO3 plane [C-Sc-C = 154.2(8)°], providing a new type of binding of this aryloxide ligand.
