Potassium trifluoro­[(Z)-3-methoxy­prop-1-en­yl]borate

Julio Zukerman-Schpector; Rafael C Guadagnin; Hélio A Stefani; Lorenzo do Canto Visentin

doi:10.1107/S1600536808036428

. 2008 Nov 13;64(Pt 12):m1525. doi: 10.1107/S1600536808036428

Potassium trifluoro[(Z)-3-methoxyprop-1-enyl]borate

Julio Zukerman-Schpector ^a,^*, Rafael C Guadagnin ^b, Hélio A Stefani ^b, Lorenzo do Canto Visentin ^c

PMCID: PMC2959975 PMID: 21581142

Abstract

In the title salt, K⁺·C₄H₇BF₃O⁻, the K atom is surrounded by six anions making close contacts through seven F [K⋯F = 2.779 (1)–3.048 (1) Å] and two O [K⋯O = 2.953 (2) and 3.127 (2) Å] atoms in a trivacant fac-vIC-9 icosahedral coordination geometry.

Related literature

For related structures, see: Caracelli et al. (2007 ▶); Stefani et al. (2006 ▶); For related literature, see: Ruiz-Martínez et al. (2008 ▶); Vieira et al. (2008 ▶).

Experimental

Crystal data

K⁺·C₄H₇BF₃O⁻
M _r = 178.01
Monoclinic,
a = 10.882 (2) Å
b = 7.2668 (15) Å
c = 9.2317 (18) Å
β = 101.52 (3)°
V = 715.3 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.72 mm⁻¹
T = 291 (2) K
0.31 × 0.22 × 0.11 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2006 ▶) T _min = 0.804, T _max = 0.924
16605 measured reflections
1327 independent reflections
1182 reflections with I > 2σ(I)
R _int = 0.059

Refinement

R[F ² > 2σ(F ²)] = 0.027
wR(F ²) = 0.072
S = 1.00
1327 reflections
92 parameters
H-atom parameters constrained
Δρ_max = 0.25 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Data collection: COLLECT (Nonius, 1998 ▶); cell refinement: PHICHI (Duisenberg et al., 2000 ▶); data reduction: EVAL-14 (CCD) (Duisenberg et al., 2003 ▶); program(s) used to solve structure: SIR97 (Altomare et al., 1999 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808036428/ng2510sup1.cif

e-64-m1525-sup1.cif^{(13.6KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808036428/ng2510Isup2.hkl

e-64-m1525-Isup2.hkl^{(64.2KB, hkl)}

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

Acknowledgments

We thank FAPESP (07/59404–2 to HAS and 08/02531–5 to JZS), CNPq (300613/2007 to HAS and 307121/2006–0 to JZS) and CAPES for financial support.

supplementary crystallographic information

Comment

Organic compounds of tellurium, such as Z-vinylic tellurides, are important synthetic precursors of organometallic molecules and organic salts and can be useful in the synthesis of new potassium vinyl trifluoroborate salts. Organotrifluoroborates represent an alternative to boronic acids, boronate esters, and organoboranes for use in the Suzuki-Miyaura reaction and other transition-metal-catalyzed cross-coupling reactions (Vieira et al. 2008). Following the ideas of Ruiz-Martínez et al. (2008) the geometry around the K⁺ ion can be described as a trivacant icosahedron, fac-vIC-9, a non spherical shape, as shown in Figure 2. The independent molecules in (I) are connected via C3···F2ⁱ = 3.214 (2) Å, C3—H3B···F2ⁱ = 137° (i = x - 1/2, -y + 3/2, z).

Experimental

nBuLi (0.8 mmol) was added dropwise at 203 K to a solution of the appropriated Z-vinylic telluride (1 mmol) in Et₂O (6 ml). The bath temperature was raised to 253 K. After 20 minutes B(OiPr)₃ (1.0 mmol) was added at 233 K. After 1 h, a aqueous solution of KHF₂ (4 mmol in 10 ml of water) was added to the reaction mixture. Then, the solvent and water were eliminated by evaporation. To the obtained solid hot acetone was added and the bulk reactional was filtered and dried, yielding 67% of (Z)-potassium vinyltrifluoroborate salt. Single crystals were obtained by slow evaporation from Et₂O.