LiYbCl4(THF)4

Lukas Richtera; Vojtech Jancik; Sona Hermanova; Karel Krpoun; Kimberly Thompson-Montero

doi:10.1107/S1600536811014395

. 2011 May 7;67(Pt 6):m700. doi: 10.1107/S1600536811014395

LiYbCl₄(THF)₄

Lukas Richtera ^a, Vojtech Jancik ^b,^*, Sona Hermanova ^a, Karel Krpoun ^a, Kimberly Thompson-Montero ^b

PMCID: PMC3120567 PMID: 21754604

Abstract

The title compound, di-μ-chlorido-dichlorido-1κ² Cl-tetrakis(tetrahydrofuran)-1κ² O,2κ² O-lithiumytterbium(III), [LiYbCl₄(C₄H₈O)₄], was prepared by the reaction of YbCl₃(THF)₃ with LiCl in THF (THF is tetrahydrofuran). The central motif of the structure is a Yb(μ-Cl)₂Li ring. The Yb atom is hexacoordinated to four Cl atoms and two THF molecules oriented in a trans fashion. The Li atom has a tetrahedral environment and is coordinated to two Cl atoms and two THF molecules. No intermolecular interactions other than van der Waals forces were observed. Two of the THF molecules are disordered over two positions.

Related literature

For the isotypic yttrium compound, see Mingqing et al. (1986 ▶). For similar lithium compounds with other trivalent cations, see: Chitsaz et al. (2001 ▶) for V^III; Neumüller et al. (1996 ▶) for Ti^III; McGuinness et al. (2006 ▶) for Cr^III.

Experimental

Crystal data

[LiYbCl₄(C₄H₈O)₄]
M _r = 610.20
Monoclinic,
a = 20.9150 (14) Å
b = 10.1565 (7) Å
c = 21.8810 (14) Å
β = 91.376 (1)°
V = 4646.7 (5) Å³
Z = 8
Mo Kα radiation
μ = 4.50 mm⁻¹
T = 100 K
0.37 × 0.16 × 0.14 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T _min = 0.430, T _max = 0.543
17457 measured reflections
4040 independent reflections
3804 reflections with I > 2σ(I)
R _int = 0.020

Refinement

R[F ² > 2σ(F ²)] = 0.023
wR(F ²) = 0.050
S = 1.22
4040 reflections
302 parameters
388 restraints
H-atom parameters constrained
Δρ_max = 1.06 e Å⁻³
Δρ_min = −1.81 e Å⁻³

Data collection: APEX2 (Bruker, 2004 ▶); cell refinement: SAINT (Bruker, 2004 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: GRETEP (Laugier & Bochu, 2003 ▶); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 ▶).

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811014395/fi2106sup1.cif

e-67-0m700-sup1.cif^{(25.9KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811014395/fi2106Isup2.hkl

e-67-0m700-Isup2.hkl^{(198.1KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The financial support of MSMT (grant No. MSM0021630501), CONACyT (grant No. 79531) and DGAPA-UNAM (PAPIIT grant No. IN205108) is gratefully acknowledged.

supplementary crystallographic information

Comment

Lanthanide compounds containing small ligands can easily form adducts or complex structures with electron donating ligands such as oxygen, halogenides etc. It is well known, that in presence of a Lewis acid such as lithium, mixed metal complexes can be formed. Thus, the reaction of YbCl₃(THF)₃ with LiCl in THF resulted in the formation of LiYbCl₄(THF)₄ as the only product (Scheme 1). Two types of chlorine atoms can be observed in the molecule: two terminal ones, which are coordinated to the ytterbium atom, whereas the other two are bridging the ytterbium and lithium atoms. The coordination spheres of the metals are completed by four THF molecules (two per metal) resulting in a hexacoordinated octahedral environment on the ytterbium atom and tetrahedral coordination on the lithium atom. The THF molecules on the ytterbium center are oriented trans to each other with an angle of 179.0 (5)° (for the major position of O1). The values for the cis Cl—Yb—Cl angles show high variation (82.95 (3) – 99.06 (3)°) due to the coordination of Cl1 and Cl2 to the lithium center, which results also in 172.39 (3)° and 171.11 (3)° trans Cl—Yb—Cl angles. The tetrahedron arround the lithium atom is also disordered with the angles ranging from 94.9 (2) to 114.2 (3)°. The molecular structure of LiYbCl₄(THF)₄ is depicted in Figure 1.

Experimental

YbCl₃(THF)₃ (200 mg, 0.4 mmol) and LiCl (25.7 mg, 0.6 mmol) were mixed as solids in a schlenk flask and THF (10 ml) was added at ambient temperature. The mixture was stirred for 4 h. During this time, both components dissolved completely. The resulting solution was filtered and the solvent evaporated under vacuum to dryness. The product was obtained in a form of transparent colourless crystals in 86% yield. Single crystals were obtained from a saturated THF solution at -30 °C.