Tetra­aceto­nitrile­lithium tetra­iso­thio­cyanato­borate

The crystal structure of the title salt, [Li(CH₃CN)₄][B(NCS)₄], is composed of discrete cations and anions. Both the Li and B atoms show a tetra­hedral coordination by four equal ligands. The aceto­nitrile and iso­thio­cyanate ligands are linear. The bond angles at the B atom are close to the ideal tetra­hedral value [108.92 (18)-109.94 (16)°], but the bond angles at the Li atom show larger deviations [106.15 (17)-113.70 (17)°].

Key indicators

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.038
• wR factor = 0.092
• Data-to-parameter ratio = 16.0

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT230_ALERT_2_B Hirshfeld Test Diff for    S2     --  C2      ..        8.8 su
PLAT230_ALERT_2_B Hirshfeld Test Diff for    S3     --  C3      ..       11.8 su
PLAT230_ALERT_2_B Hirshfeld Test Diff for    S4     --  C4      ..        8.8 su
PLAT230_ALERT_2_B Hirshfeld Test Diff for    N3     --  C3      ..       10.1 su

Alert level C
PLAT230_ALERT_2_C Hirshfeld Test Diff for    S1     --  C1      ..        6.2 su
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        C61
PLAT906_ALERT_3_C Large K value in the Analysis of Variance ......     11.437
PLAT906_ALERT_3_C Large K value in the Analysis of Variance ......      2.296
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          9
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.595          3

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF          ?
PLAT042_ALERT_1_G Calc. and Reported MoietyFormula Strings  Differ          ?
PLAT909_ALERT_3_G Percentage of Observed Data at Theta(Max) still          52 Perc.

   0 ALERT level A = Most likely a serious problem - resolve or explain
   4 ALERT level B = A potentially serious problem, consider carefully
   6 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   3 ALERT level G = General information/check it is not something unexpected

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   6 ALERT type 2 Indicator that the structure model may be wrong or deficient
   5 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

Our group is interested in the synthesis of novel and improved electrolytes, namely, borates with alkinyl or catecholate ligands (Lerner et al., 2007, 2012; Röder et al., 2008). In the course of our investigations we synthesized the literature-reported borate Li[B(NCS)₄] (Kleemann & Newman 1981) to compare its electrochemical properties with those of the borates which we have prepared. We were able to get crystals of this so far structurally uncharacterized borate Li(CH₃CN)₄[B(NCS)₄]. The borate Li(CH₃CN)₄[B(NCS)₄] was synthesized from BF₃(OEt₂) and Li[NCS], as shown in Figure 1.

The crystal structure of [Li(CH₃CN)₄]⁺[B(NCS)₄]^- is composed of discrete cations and anions (Fig. 2). Both the Li and B centre, show a tetrahedral coordination by four equal ligands. The acetonitrile and the isothiocyanate ligands are linear. Whereas the bond angles at the boron centre [108.92 (18)° - 109.94 (16)°] are very close to the ideal tetrahedral value, the bond angles around the Li centre [106.15 (17)° - 113.70 (17)°] show larger deviations from the ideal value.

Related literature

Our group is interested in the synthesis of novel and improved electrolytes, namely borates with alkinyl or catecholate ligands, see: Lerner et al. (2007, 2012); Röder et al. (2008). For the preparation, see: Kleemann & Newman (1981).

S2. Experimental

Li(CH₃CN)₄[B(NCS)₄]: The borate Li(CH₃CN)₄[B(NCS)₄] was prepared according to a literature procedure (Kleemann & Newman 1981). X-ray quality crystals of Li(CH₃CN)₄[B(NCS)₄] were grown from an acetonitrile solution at room temperature.

S3. Refinement

All H atoms were located in difference Fourier maps. Nevertheless, they were geometrically positioned and refined using a riding model with C—H = 0.98 Å and with U_iso(H) = 1.5U_eq(C). The methyl groups were allowed to rotate but not to tip.

Computing details

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA (Stoe & Cie, 2001); data reduction: X-AREA (Stoe & Cie, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2010).

Figures

	Fig. 1. Synthesis of Li(CH3CN)4[B(NCS)4]. (i) -3LiF; in CH3CN.
	Fig. 2. A perspective view of the title compound showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii.

Tetraacetonitrilelithium tetraisothiocyanatoborate

Crystal data

[Li(C2H3N)4](C4BN4S4)	F(000) = 1696
Mr = 414.29	Dx = 1.269 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 13942 reflections
a = 21.219 (3) Å	θ = 3.6–26.8°
b = 9.4756 (14) Å	µ = 0.45 mm^−1
c = 21.596 (4) Å	T = 173 K
β = 92.845 (10)°	Block, colourless
V = 4336.8 (12) Å^3	0.35 × 0.29 × 0.15 mm
Z = 8

Data collection

Stoe IPDS II two-circle diffractometer	3816 independent reflections
Radiation source: Genix 3D IµS microfocus X-ray source	2681 reflections with I > 2σ(I)
Genix 3D multilayer optics monochromator	Rint = 0.074
ω scans	θmax = 25.0°, θmin = 3.6°
Absorption correction: multi-scan (X-AREA; Stoe & Cie, 2001)	h = −25→25
Tmin = 0.858, Tmax = 0.936	k = −11→11
24466 measured reflections	l = −25→25

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.092	H-atom parameters constrained
S = 0.97	w = 1/[σ^2(Fo^2) + (0.0478P)^2] where P = (Fo^2 + 2Fc^2)/3
3816 reflections	(Δ/σ)max = 0.032
239 parameters	Δρmax = 0.18 e Å^−3
0 restraints	Δρmin = −0.25 e Å^−3

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
B1	0.60133 (11)	0.2457 (2)	0.70356 (11)	0.0313 (4)
N1	0.61748 (7)	0.15384 (18)	0.65017 (8)	0.0385 (4)
C1	0.62999 (8)	0.0914 (2)	0.60595 (10)	0.0353 (4)
S1	0.64743 (3)	0.00457 (7)	0.54619 (3)	0.06209 (19)
N2	0.65695 (7)	0.33656 (17)	0.72237 (8)	0.0378 (4)
C2	0.69788 (9)	0.4127 (2)	0.73635 (9)	0.0384 (5)
S2	0.75423 (3)	0.51599 (7)	0.75594 (3)	0.0673 (2)
N3	0.54597 (7)	0.33778 (16)	0.68497 (7)	0.0355 (4)
C3	0.50357 (8)	0.4078 (2)	0.66964 (8)	0.0346 (4)
S3	0.44491 (3)	0.50352 (7)	0.64826 (3)	0.06058 (19)
N4	0.58433 (7)	0.15490 (16)	0.75811 (8)	0.0355 (4)
C4	0.57138 (8)	0.0892 (2)	0.80105 (9)	0.0349 (4)
S4	0.55383 (3)	−0.00256 (7)	0.85961 (3)	0.06261 (19)
Li1	0.34824 (15)	0.4840 (3)	0.44482 (16)	0.0416 (8)
N5	0.42234 (8)	0.6002 (2)	0.47394 (8)	0.0461 (4)
C51	0.46315 (9)	0.6718 (2)	0.48727 (9)	0.0389 (5)
C52	0.51502 (11)	0.7646 (3)	0.50381 (13)	0.0613 (7)
H52A	0.5480	0.7536	0.4740	0.092*
H52B	0.5323	0.7409	0.5455	0.092*
H52C	0.5001	0.8625	0.5033	0.092*
N6	0.27497 (8)	0.61203 (19)	0.42481 (8)	0.0464 (4)
C61	0.23575 (9)	0.6908 (2)	0.41537 (9)	0.0386 (5)
C62	0.18563 (11)	0.7913 (3)	0.40324 (13)	0.0620 (7)
H62A	0.1819	0.8524	0.4395	0.093*
H62B	0.1458	0.7410	0.3948	0.093*
H62C	0.1952	0.8490	0.3672	0.093*
N7	0.32273 (8)	0.36138 (19)	0.51545 (9)	0.0461 (4)
C71	0.30814 (8)	0.3053 (2)	0.55915 (10)	0.0364 (4)
C72	0.28959 (12)	0.2348 (3)	0.61477 (11)	0.0542 (6)
H72A	0.3192	0.2594	0.6494	0.081*
H72B	0.2901	0.1324	0.6083	0.081*
H72C	0.2469	0.2647	0.6243	0.081*
N8	0.37312 (8)	0.36597 (19)	0.37288 (9)	0.0444 (4)
C81	0.38851 (9)	0.3023 (2)	0.33200 (11)	0.0398 (5)
C82	0.40806 (13)	0.2207 (3)	0.27914 (13)	0.0646 (7)
H82A	0.3716	0.1704	0.2603	0.097*
H82B	0.4405	0.1525	0.2930	0.097*
H82C	0.4253	0.2844	0.2485	0.097*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
B1	0.0281 (9)	0.0337 (10)	0.0321 (11)	0.0005 (8)	0.0013 (8)	0.0031 (9)
N1	0.0373 (8)	0.0408 (9)	0.0376 (10)	0.0027 (7)	0.0043 (7)	−0.0003 (8)
C1	0.0313 (9)	0.0317 (10)	0.0429 (12)	−0.0012 (7)	0.0029 (8)	0.0024 (9)
S1	0.0764 (4)	0.0521 (4)	0.0592 (4)	−0.0026 (3)	0.0184 (3)	−0.0211 (3)
N2	0.0326 (8)	0.0397 (9)	0.0408 (10)	−0.0015 (7)	0.0002 (7)	0.0026 (7)
C2	0.0355 (10)	0.0433 (11)	0.0362 (11)	0.0007 (9)	−0.0006 (8)	0.0079 (9)
S2	0.0574 (4)	0.0733 (4)	0.0692 (4)	−0.0323 (3)	−0.0161 (3)	0.0098 (3)
N3	0.0304 (8)	0.0381 (9)	0.0379 (9)	0.0059 (7)	0.0014 (7)	0.0063 (7)
C3	0.0363 (10)	0.0379 (10)	0.0299 (10)	−0.0035 (8)	0.0042 (8)	0.0033 (8)
S3	0.0462 (3)	0.0712 (4)	0.0640 (4)	0.0258 (3)	−0.0017 (3)	0.0165 (3)
N4	0.0356 (8)	0.0364 (8)	0.0345 (9)	0.0019 (7)	0.0018 (7)	0.0053 (8)
C4	0.0346 (9)	0.0342 (10)	0.0358 (11)	0.0057 (8)	0.0012 (8)	−0.0002 (9)
S4	0.0843 (4)	0.0581 (4)	0.0470 (4)	0.0039 (3)	0.0194 (3)	0.0217 (3)
Li1	0.0411 (16)	0.0402 (18)	0.0440 (19)	0.0036 (15)	0.0058 (14)	−0.0016 (16)
N5	0.0415 (9)	0.0511 (11)	0.0457 (11)	−0.0003 (8)	0.0024 (8)	0.0040 (8)
C51	0.0370 (10)	0.0427 (11)	0.0369 (11)	0.0075 (9)	0.0026 (8)	0.0065 (9)
C52	0.0456 (14)	0.0583 (15)	0.0791 (19)	−0.0065 (10)	−0.0060 (13)	−0.0049 (13)
N6	0.0430 (9)	0.0462 (10)	0.0503 (11)	0.0022 (8)	0.0063 (8)	0.0010 (8)
C61	0.0400 (10)	0.0378 (11)	0.0382 (11)	−0.0022 (9)	0.0047 (8)	−0.0038 (9)
C62	0.0579 (14)	0.0531 (14)	0.0741 (18)	0.0181 (11)	−0.0067 (13)	−0.0046 (13)
N7	0.0463 (9)	0.0457 (10)	0.0464 (11)	−0.0019 (8)	0.0051 (8)	0.0002 (9)
C71	0.0320 (9)	0.0353 (10)	0.0415 (12)	−0.0019 (8)	−0.0015 (8)	−0.0067 (9)
C72	0.0594 (14)	0.0597 (15)	0.0436 (13)	−0.0108 (11)	0.0026 (11)	0.0079 (11)
N8	0.0460 (9)	0.0428 (10)	0.0445 (11)	0.0013 (8)	0.0043 (8)	0.0028 (9)
C81	0.0384 (10)	0.0357 (11)	0.0454 (13)	−0.0015 (8)	0.0028 (9)	0.0067 (10)
C82	0.0736 (17)	0.0627 (16)	0.0587 (16)	0.0072 (13)	0.0154 (13)	−0.0113 (13)

Geometric parameters (Å, º)

B1—N1	1.498 (3)	C52—H52A	0.9800
B1—N2	1.501 (3)	C52—H52B	0.9800
B1—N3	1.502 (2)	C52—H52C	0.9800
B1—N4	1.516 (3)	N6—C61	1.129 (2)
N1—C1	1.165 (3)	C61—C62	1.442 (3)
C1—S1	1.589 (2)	C62—H62A	0.9800
N2—C2	1.158 (2)	C62—H62B	0.9800
C2—S2	1.586 (2)	C62—H62C	0.9800
N3—C3	1.153 (2)	N7—C71	1.139 (3)
C3—S3	1.5900 (19)	C71—C72	1.446 (3)
N4—C4	1.161 (2)	C72—H72A	0.9800
C4—S4	1.594 (2)	C72—H72B	0.9800
Li1—N5	1.995 (4)	C72—H72C	0.9800
Li1—N6	2.002 (4)	N8—C81	1.131 (3)
Li1—N8	2.006 (4)	C81—C82	1.456 (4)
Li1—N7	2.013 (4)	C82—H82A	0.9800
N5—C51	1.126 (2)	C82—H82B	0.9800
C51—C52	1.440 (3)	C82—H82C	0.9800
N1—B1—N2	109.56 (18)	H52A—C52—H52C	109.5
N1—B1—N3	109.73 (15)	H52B—C52—H52C	109.5
N2—B1—N3	109.44 (15)	C61—N6—Li1	175.7 (2)
N1—B1—N4	109.94 (16)	N6—C61—C62	179.9 (3)
N2—B1—N4	109.24 (16)	C61—C62—H62A	109.5
N3—B1—N4	108.92 (18)	C61—C62—H62B	109.5
C1—N1—B1	174.95 (19)	H62A—C62—H62B	109.5
N1—C1—S1	179.26 (19)	C61—C62—H62C	109.5
C2—N2—B1	176.46 (18)	H62A—C62—H62C	109.5
N2—C2—S2	179.5 (2)	H62B—C62—H62C	109.5
C3—N3—B1	178.8 (2)	C71—N7—Li1	172.5 (2)
N3—C3—S3	179.6 (2)	N7—C71—C72	179.7 (3)
C4—N4—B1	177.82 (19)	C71—C72—H72A	109.5
N4—C4—S4	179.3 (2)	C71—C72—H72B	109.5
N5—Li1—N6	108.97 (17)	H72A—C72—H72B	109.5
N5—Li1—N8	108.54 (17)	C71—C72—H72C	109.5
N6—Li1—N8	113.70 (17)	H72A—C72—H72C	109.5
N5—Li1—N7	108.48 (17)	H72B—C72—H72C	109.5
N6—Li1—N7	106.15 (17)	C81—N8—Li1	178.0 (2)
N8—Li1—N7	110.86 (17)	N8—C81—C82	179.7 (3)
C51—N5—Li1	175.4 (2)	C81—C82—H82A	109.5
N5—C51—C52	179.3 (2)	C81—C82—H82B	109.5
C51—C52—H52A	109.5	H82A—C82—H82B	109.5
C51—C52—H52B	109.5	C81—C82—H82C	109.5
H52A—C52—H52B	109.5	H82A—C82—H82C	109.5
C51—C52—H52C	109.5	H82B—C82—H82C	109.5