Structural diversity of bis(pentamethylcyclopentadienyl)lanthanide halide complexes: x-ray crystal structures of [(C5Me5)2SmCl]3 and (C5Me5)10Sm5Cl5[Me(OCH2CH2)4OMe]

Displacement, reduction, and ligand redistribution reactivity of the cationic mono-C5Me5 Ln2+ complexes (C5Me5)Ln(BPh4) (Ln=Sm, Yb)

“…The symmetry equivalent, doubly-bridging chloride ligands, Cl (2) Sm] 4 as well as the 2.67-3.09(1) Å Sm-(l 3 -Cl) distances in (C 5 H 5 ) 12 Sm 12 (l 3 -Cl) 24 [31]. The Sm(1)-(C 5 Me 5 ring centroid) distance of 2.379 Å is shorter than the 2.43-2.47 Å seen in (C 5 Me 5 ) 2 SmCl(THF) [25], but similar to the 2.376 Å observed for the samarium with one (C 5 Me 5 ) 1À ligand in [(C 5 Me 5 ) 2 Sm](lCl) 6 …”

“…(7). Neither of the common ligand redistribution products, [(C 5 Me 5 ) 2 SmCl] 3 [25] nor (C 5 Me 5 ) 2 SmCl(THF) [26], were observed in the 1 H NMR spectrum. …”

Syntheses and Structures of Bis(aryloxo)fluoroytterbium(III) Complexes, [Yb(OAr)2F(THF)]2 (OAr = OC6H2-2,6-tBu2-4-R; R = H, Me, tBu), and Bis(cyclopentadienyl)fluoroytterbium(III) Complexes, [YbCp2F]3, [Yb(MeCp)2F]4, [YbCp2F(OPPh3)]2, and [Yb(MeCp)2F(THF)]2

“…17 (Figure 3 and refs. [15,20,42] ), the present complex has the largest X-Ln-X (X ϭ Cl or F) angle and the smallest Ln-X-Ln angle, a result that is unexpected since the group contains the complex of the much smaller Sc 3ϩ . Although the cen-Yb-cen (cen ϭ centroid of a Cp ring) angle is in the range (127-140°) for 8-coordinate complexes, it is close to the overlap with the range (113-129°) for 9-coordinate complexes (see literature cited in ref.…”

“…[42] Selected bond lengths and angles are given in (9) Yb (1) Table 4 and the structure is shown in Figure 3. The structure features a planar Yb 3 F 3 ring with near equal Yb-F bond lengths, but with one Yb-F-Yb and one F-Yb-F angle slightly different from the other two.…”

“…However, these slight variations are of little consequence and the structure is sufficiently symmetrical for ν(Yb-F) to be infrared inactive and observed only in the Raman spectrum (Table 1). There is little variation in ϽLn-CϾ bond lengths between [YbCp 2 F] 3 ( Figure 3) and [ScCp 2 F] 3 , [15] [Sm(C 5 H 4 -tBu) 2 F] 3 [20] and [Sm(C 5 Me 5 )Cl] 3 [42] and in ϽLn-FϾ between the three fluorides, when allowance is made for variation in Ln 3ϩ radii. Thus subtraction of the ionic radius for eightcoordinate Ln 3ϩ from ϽLn-CϾ gives 1.61, 1.60, 1.63, and 1.65 Å for the respective compounds.…”