Syntheses and reactivities of bisaryloxo lanthanide chlorides and crystal structures of [Ln(ArO) 2Cl(THF) 2]·(MePh) (Ln=Er, Yb) and [Sm(ArO) 2(THF) 3]·(MePh) (ArO=2,6-di- tert-butyl-4-methylphenoxo)

Abstract

Four bisaryloxo lanthanide chlorides Ln(ArO) 2Cl(THF) 2 (Ln=Sm ( 1), Er ( 2), Yb ( 3), Y ( 4)) (ArO=2,6-di- tert-butyl-4-methylphenoxo) were synthesized by the reaction of anhydrous LnCl 3 with 2 equiv. of NaOAr in THF at room temperature in high yield. These chlorides can be used as starting materials to synthesize heteroleptic lanthanide aryloxides. Complex 3 reacted with 1 equiv. of MeCpNa in THF to form a complex (MeCp)Yb(ArO) 2(THF) ( 5) containing mixed ligands. The divalent aryloxo lanthanide complexes Sm(ArO) 2(THF) 3 ( 6) and Yb(ArO) 2(THF) 3 ( 7) were obtained in good yield by reducing compounds 1 and 3 with sodium metal in THF, respectively. Single crystal structures of complexes 2·PhMe, 3·PhMe and 6·PhMe were determined. Complexes 2 and 3 are isostructural, in which one chlorine atom, two aryloxo ligands and two THF molecules are coordinated to the central metal to form a distorted trigonal bipyramid geometry. Complex 6 has similar stereochemistry to that of 2 and 3.