Buy article online - an online subscription or single-article purchase is required to access this article.
Download citation
Download citation
link to html
The title compound, [Li(C12H21NSi)(C6H16N2)], is an intermediate in the synthesis of the corresponding organometallic compounds. The mol­ecule has an unusual C-Si-N-Li four-membered heterocycle which adopts a folded conformation, with the coordination around the Li, N, C and Si atoms being distorted tetrahedral. Its structure is strongly supported by 1H NMR, 13C NMR and 13C-1H correlation spectra. The compound has potential for application in the synthesis of other novel organometallic compounds.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270104000836/sq1140sup1.cif
Contains datablocks global, I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S0108270104000836/sq1140Isup2.hkl
Contains datablock I

CCDC reference: 235312

Comment top

Organolithium compounds, as versatile ligands in organometallic chemistry, have attracted intensive research interest since the first such compound was discovered (Sapse & Schleyer, 1995). In this field, Lappert and co-workers have made a number of key investigations over the years. An attractive area of their investigations is that the interaction of a trimethylsilylmethyl lithium reagent, Li[CHR2] (R is SiMe3), with an α-hydrogen-free nitrile, R'CN, can yield α-l-azaallyl- (A), β-diketiminato- (B) and 1,3-diazaallyllithium (C) (Hitchcock et al., 2000). Their work aroused our interest in seeking novel organolithium ligands by introducing one or two N atoms into the ligands. Our initial objectives are to discover new organolithium ligands and to investigate their structures. Further objectives are to use them as ligand-transfer reagents in order to gain access to a wider range of metal alkyls, and to use them as substrates for synthesis. Our initial target ligands were of the general formulae {PhCH[SiMe[N(CH3)2]2]}Li and {PhCH[SiMe2N(CH3)2]}Li. These compounds have a number of useful features. Firstly, they are chiral, secondly, they are of relative migratory potential in C—Si cleavage reactions, and thirdly, the chosen substituent –N(CH3)2 group is a potential coordination site. Thus, we have synthesized the title complex, (I), and its structure is reported here. Compound (I) has also been characterized by 1H NMR, 13C NMR and 13C-1H correlation spectra. Its structure shows several interesting features, which will now be discussed. \sch

Selected geometric parameters of (I) are listed in Table 1 and the molecular structure is illustrated in Fig. 1. There is a central C1—Si1—N1—Li1 four-membered ring which adopts a folded conformation, with the dihedral angle between the C1—Li1—N1 and C1—Si1—N1 planes being 21.9 (1)° and with the coordination around the Li1, N1, C1 and Si1 atoms being distorted tetrahedral.

The C1—Si1 bond length [1.787 (2) Å] is much shorter than common Si-Csp3 bonds, which usually lie in the range 1.861–1.901 Å, and this can be attributed to delocalization of the negative charge, either by ππ bonding or, more likely, to negative hyperconjugation (Schleyer et al., 1984; Brinkman et al., 1994), leading to some double-bond character in the Si1—C1 bond. A similarly short bond length [1.793 (6) Å] is observed in the compound [(Me2NMe2Si)3CLi] (Adam et al., 1996).

The Si1—N1 bond length [1.783 (2) Å] is longer than common Si—N bonds [1.710–1.721 Å] between three-coordinate N atoms and four-coordinate Si atoms in R3SiNR2 species (Lukevics et al., 1985). A similarly long bond length [1.792 (4) Å] is observed in the compound [(Me2NMe2Si)3CLi] (Adam et al., 1996). It is a consequence of the coordination of the N1 atom to atom Li1 and indicates a decrease in the strength of the interaction of atom Si1 with atom N1 in the molecule.

There is a rather distorted tetrahedral arrangement around the Li atom, with bond angles ranging from 81.60 (15) to 127.43 (19)°. The dihedral angle between the N4—Si1—C1 and C1—Si1—N1 planes is 59.4 (1)°, which indicates that the terminal N4 group is bent substantially out of the central ring system. The N4—Si1—N1—Li1 torsion angle of 142.46 (13)° indicates a trans-configuration of the molecule about the Si1—N1 bond. The C8—Si1—C1 and Si1—C1—Li1 planes are almost perpendicular [dihedral angle 96.76 (15)°].

All of these features, i.e. the longer bond length of Si1—N1, the shorter bond length of Si1—C1, the rather distorted tetrahedral arrangement around the Li atom, the trans configuration of the molecule about the Si1—N1 bond and the folded conformation of the C1—Si1—N1—Li1 four-membered ring, are required to minimize intra-molecular steric strain.

It is noteworthy that, in the solid, {PhCH[SiMe[N(CH3)2]2]}Li exists as a monomer in which one –NMe2 group is engaged in coordination to the Li atom. Much novel chemistry has emerged through applying the very bulky ligand {PhCH[SiMe[N(CH3)2]2]} to a wide range of metals and metalloids. Even more unusual species might be expected to be formed by the use of (I) as a source of novel organometallic compounds, in which the amino group is available to coordinate either to the metal atom to which the central C atom is attached, to another metal centre, or to both. Studies of these possibilities are under way.

Experimental top

n-Butyllithium was added dropwise to a solution of toluene and TMEDA (TMEDA is N,N,N,N-tetramethylethylenediamine; molar ratio 1:1:1) in hexane at 273 K and the temperature was allowed to rise to room temperature. The mixture was stirred for more than 24 h and then an equimolar amount of bis(dimethylamino)methylchlorosilane was added at 273 K and the temperature was allowed to rise to room temperature. The mixture was stirred for a further 15 h, yielding a white precipitate (LiCl), which was removed by filtration. The compound benzylbis(dimethylamino)methylsilane was isolated as a colourless liquid by vacuum distillation of the filtrate. A solution of n-butyllithium in hexane was slowly added to benzylbis(dimethylamino)methylsilane and TMEDA in pentane (molar ratio 1:1:1) at ambient temperature. The mixture was stirred for 18 h. The solution was concentrated carefully under vacuum, yielding yellow crystals of (I). Crystals suitable for single-crystal X-ray diffraction were grown from a concentrated hexane solution at 253 K. All reactions were performed under argon using standard Schlenk techniques. The hexane was dried by distilling with a sodium-potassium alloy; the pentane was distilled from a drying agent with sodium. Spectroscopic analysis: 1H NMR (C6D6, δ, p.p.m.): 6.99–7.23 (m, 5H), 2.75 (m, 12H), 2.45 (s, 1H), 1.58–2.21 (m, 16H), 0.34 (s, 3H); 13C NMR (C6D6,δ, p.p.m.): 156.1, 119.8, 109.4, 56.2, 45.2, 39.5, 38.6, 37.5, 24.2, −3.0.

Refinement top

All H atoms were initially located in a difference Fourier map. H atoms on Csp3 were then constrained to an ideal geometry, with C—H distances of 0.96–0.98 Å and with Uiso(H) = 1.5Ueq(C). H atoms on Csp2 were allowed to ride on their parent atoms, with C—H distances of 0.93 Å and with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1998); software used to prepare material for publication: SHELXTL.

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are represented by spheres of arbitrary radii.
[Benzylbis(dimethylamino)methylsilyl-κ2C,N](N,N,N',N'- tetramethylethylenediamine-κ2N,N)lithium(I) top
Crystal data top
[Li(C12H21NSi)(C6H16N2)]F(000) = 760
Mr = 344.55Dx = 1.051 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 13.946 (4) ÅCell parameters from 1985 reflections
b = 9.805 (2) Åθ = 2.4–22.5°
c = 17.236 (4) ŵ = 0.11 mm1
β = 112.523 (3)°T = 183 K
V = 2177.0 (9) Å3Block, yellow
Z = 40.40 × 0.30 × 0.20 mm
Data collection top
Bruker SMART CCD are-detector
diffractometer
3841 independent reflections
Radiation source: oil sealed2779 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.040
Detector resolution: 100x100 microns pixels mm-1θmax = 25.0°, θmin = 1.6°
ω scansh = 1616
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
k = 1111
Tmin = 0.956, Tmax = 0.978l = 1420
8766 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.060Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.134H-atom parameters constrained
S = 1.00 w = 1/[σ2(Fo2) + (0.061P)2]
where P = (Fo2 + 2Fc2)/3
3841 reflections(Δ/σ)max < 0.001
226 parametersΔρmax = 0.32 e Å3
0 restraintsΔρmin = 0.18 e Å3
Crystal data top
[Li(C12H21NSi)(C6H16N2)]V = 2177.0 (9) Å3
Mr = 344.55Z = 4
Monoclinic, P21/cMo Kα radiation
a = 13.946 (4) ŵ = 0.11 mm1
b = 9.805 (2) ÅT = 183 K
c = 17.236 (4) Å0.40 × 0.30 × 0.20 mm
β = 112.523 (3)°
Data collection top
Bruker SMART CCD are-detector
diffractometer
3841 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2779 reflections with I > 2σ(I)
Tmin = 0.956, Tmax = 0.978Rint = 0.040
8766 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0600 restraints
wR(F2) = 0.134H-atom parameters constrained
S = 1.00Δρmax = 0.32 e Å3
3841 reflectionsΔρmin = 0.18 e Å3
226 parameters
Special details top

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 (Å2) top
xyzUiso*/Ueq
Li10.2614 (3)0.6968 (4)0.0492 (3)0.0353 (10)
Si10.31514 (5)0.48302 (7)0.15322 (4)0.0343 (2)
N10.25714 (15)0.47248 (19)0.04152 (12)0.0359 (5)
N20.14917 (15)0.8301 (2)0.02853 (12)0.0353 (5)
N30.37011 (15)0.8007 (2)0.01351 (13)0.0442 (6)
N40.26295 (18)0.3533 (2)0.19169 (14)0.0479 (6)
C10.29767 (18)0.6509 (2)0.18611 (15)0.0328 (6)
H10.36470.69050.22150.039*
C20.21495 (18)0.7184 (2)0.20066 (14)0.0299 (6)
C30.11364 (18)0.6656 (2)0.17948 (15)0.0354 (6)
H30.09960.57810.15710.042*
C40.0350 (2)0.7374 (3)0.19030 (16)0.0411 (6)
H40.03030.69760.17510.049*
C50.0514 (2)0.8678 (3)0.22344 (16)0.0433 (7)
H50.00240.91720.22930.052*
C60.1495 (2)0.9224 (2)0.24749 (16)0.0406 (7)
H60.16251.00920.27100.049*
C70.22845 (19)0.8505 (2)0.23719 (14)0.0351 (6)
H70.29390.89030.25500.042*
C80.4564 (2)0.4553 (3)0.17822 (18)0.0516 (8)
H8A0.49550.47910.23580.077*
H8B0.47820.51140.14230.077*
H8C0.46830.36120.16940.077*
C90.2657 (3)0.2134 (3)0.1654 (2)0.0707 (10)
H9A0.32170.16590.20770.106*
H9B0.27600.21220.11350.106*
H9C0.20120.16930.15780.106*
C100.2429 (2)0.3618 (3)0.26728 (16)0.0474 (7)
H10A0.17650.32200.25780.071*
H10B0.24290.45570.28300.071*
H10C0.29590.31330.31150.071*
C110.1439 (2)0.4607 (3)0.00439 (18)0.0532 (8)
H11A0.11900.48680.05370.080*
H11B0.11420.51960.03380.080*
H11C0.12420.36810.00880.080*
C120.3012 (2)0.3905 (3)0.00805 (18)0.0628 (9)
H12A0.27970.29730.00900.094*
H12B0.37560.39540.01690.094*
H12C0.27720.42510.06440.094*
C130.1393 (3)0.9341 (3)0.02869 (18)0.0641 (9)
H13A0.10821.01460.00260.096*
H13B0.20670.95610.06970.096*
H13C0.09630.90000.05660.096*
C140.0453 (2)0.7849 (3)0.08167 (18)0.0597 (8)
H14A0.01220.74520.04740.089*
H14B0.04970.71820.12090.089*
H14C0.00530.86140.11180.089*
C150.1995 (2)0.8852 (3)0.08246 (18)0.0537 (8)
H15A0.16350.96730.10970.064*
H15B0.19410.81920.12590.064*
C160.3112 (2)0.9176 (3)0.03418 (19)0.0592 (8)
H16A0.34210.94810.07290.071*
H16B0.31610.99190.00430.071*
C170.4627 (2)0.8449 (4)0.0835 (2)0.0932 (13)
H17A0.49720.76690.11590.140*
H17B0.44340.90630.11840.140*
H17C0.50870.89050.06240.140*
C180.4007 (3)0.7130 (4)0.0415 (2)0.0824 (11)
H18A0.44420.76320.06300.124*
H18B0.33980.68240.08740.124*
H18C0.43800.63560.01030.124*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Li10.037 (2)0.038 (2)0.036 (2)0.0014 (19)0.019 (2)0.0026 (19)
Si10.0371 (4)0.0320 (4)0.0369 (4)0.0027 (3)0.0177 (3)0.0014 (3)
N10.0382 (12)0.0353 (11)0.0369 (13)0.0021 (9)0.0171 (10)0.0045 (10)
N20.0378 (12)0.0395 (12)0.0315 (12)0.0036 (10)0.0166 (10)0.0018 (10)
N30.0326 (12)0.0591 (15)0.0378 (13)0.0074 (11)0.0100 (11)0.0076 (11)
N40.0776 (17)0.0263 (12)0.0540 (15)0.0013 (11)0.0410 (14)0.0026 (11)
C10.0306 (14)0.0354 (14)0.0309 (14)0.0049 (11)0.0102 (12)0.0036 (11)
C20.0429 (15)0.0266 (13)0.0218 (13)0.0005 (11)0.0143 (12)0.0038 (10)
C30.0431 (16)0.0337 (14)0.0308 (15)0.0030 (12)0.0158 (13)0.0029 (11)
C40.0357 (15)0.0523 (17)0.0362 (16)0.0013 (13)0.0149 (13)0.0005 (13)
C50.0492 (18)0.0456 (17)0.0395 (17)0.0124 (13)0.0221 (14)0.0054 (13)
C60.0635 (19)0.0281 (13)0.0334 (15)0.0057 (13)0.0222 (14)0.0016 (12)
C70.0437 (16)0.0328 (14)0.0289 (14)0.0059 (12)0.0142 (12)0.0010 (11)
C80.0464 (17)0.0603 (19)0.0478 (18)0.0124 (14)0.0177 (15)0.0075 (15)
C90.111 (3)0.0355 (17)0.089 (3)0.0013 (17)0.064 (2)0.0015 (17)
C100.0569 (18)0.0447 (16)0.0423 (17)0.0016 (14)0.0208 (15)0.0064 (14)
C110.0480 (18)0.0584 (18)0.0492 (18)0.0135 (14)0.0142 (15)0.0122 (15)
C120.081 (2)0.063 (2)0.050 (2)0.0156 (17)0.0309 (18)0.0074 (16)
C130.094 (3)0.0533 (19)0.0493 (19)0.0221 (18)0.0319 (18)0.0023 (16)
C140.0437 (18)0.072 (2)0.061 (2)0.0063 (16)0.0169 (16)0.0079 (17)
C150.0484 (18)0.067 (2)0.0472 (18)0.0080 (15)0.0202 (15)0.0206 (15)
C160.054 (2)0.0605 (19)0.065 (2)0.0093 (16)0.0250 (17)0.0214 (17)
C170.060 (2)0.119 (3)0.070 (2)0.044 (2)0.0088 (19)0.030 (2)
C180.073 (2)0.113 (3)0.081 (3)0.022 (2)0.051 (2)0.016 (2)
Geometric parameters (Å, º) top
Li1—N22.085 (5)C8—H8B0.9600
Li1—N32.104 (4)C8—H8C0.9600
Li1—N12.203 (4)C9—H9A0.9600
Li1—C12.261 (5)C9—H9B0.9600
Si1—N41.720 (2)C9—H9C0.9600
Si1—N11.783 (2)C10—H10A0.9600
Si1—C11.787 (2)C10—H10B0.9600
Si1—C81.869 (3)C10—H10C0.9600
N1—C111.464 (3)C11—H11A0.9600
N1—C121.469 (3)C11—H11B0.9600
N2—C141.456 (3)C11—H11C0.9600
N2—C131.461 (3)C12—H12A0.9600
N2—C151.466 (3)C12—H12B0.9600
N3—C171.455 (3)C12—H12C0.9600
N3—C181.459 (3)C13—H13A0.9600
N3—C161.465 (3)C13—H13B0.9600
N4—C101.436 (3)C13—H13C0.9600
N4—C91.449 (3)C14—H14A0.9600
C1—C21.433 (3)C14—H14B0.9600
C1—H10.9800C14—H14C0.9600
C2—C31.415 (3)C15—C161.493 (4)
C2—C71.421 (3)C15—H15A0.9700
C3—C41.375 (3)C15—H15B0.9700
C3—H30.9300C16—H16A0.9700
C4—C51.383 (3)C16—H16B0.9700
C4—H40.9300C17—H17A0.9600
C5—C61.377 (3)C17—H17B0.9600
C5—H50.9300C17—H17C0.9600
C6—C71.376 (3)C18—H18A0.9600
C6—H60.9300C18—H18B0.9600
C7—H70.9300C18—H18C0.9600
C8—H8A0.9600
N2—Li1—N387.48 (17)H8B—C8—H8C109.5
N2—Li1—N1126.2 (2)N4—C9—H9A109.5
N3—Li1—N1118.18 (19)N4—C9—H9B109.5
N2—Li1—C1127.43 (19)H9A—C9—H9B109.5
N3—Li1—C1120.2 (2)N4—C9—H9C109.5
N1—Li1—C181.60 (15)H9A—C9—H9C109.5
N4—Si1—N1106.83 (11)H9B—C9—H9C109.5
N4—Si1—C1115.45 (10)N4—C10—H10A109.5
N1—Si1—C1109.59 (10)N4—C10—H10B109.5
N4—Si1—C8111.60 (12)H10A—C10—H10B109.5
N1—Si1—C8104.05 (11)N4—C10—H10C109.5
C1—Si1—C8108.69 (12)H10A—C10—H10C109.5
C11—N1—C12108.9 (2)H10B—C10—H10C109.5
C11—N1—Si1116.35 (16)N1—C11—H11A109.5
C12—N1—Si1122.83 (17)N1—C11—H11B109.5
C11—N1—Li196.01 (17)H11A—C11—H11B109.5
C12—N1—Li1125.01 (19)N1—C11—H11C109.5
Si1—N1—Li183.49 (13)H11A—C11—H11C109.5
C14—N2—C13108.0 (2)H11B—C11—H11C109.5
C14—N2—C15108.4 (2)N1—C12—H12A109.5
C13—N2—C15111.3 (2)N1—C12—H12B109.5
C14—N2—Li1122.3 (2)H12A—C12—H12B109.5
C13—N2—Li1104.23 (19)N1—C12—H12C109.5
C15—N2—Li1102.37 (17)H12A—C12—H12C109.5
C17—N3—C18109.1 (3)H12B—C12—H12C109.5
C17—N3—C16111.2 (2)N2—C13—H13A109.5
C18—N3—C16109.7 (2)N2—C13—H13B109.5
C17—N3—Li1114.3 (2)H13A—C13—H13B109.5
C18—N3—Li1109.0 (2)N2—C13—H13C109.5
C16—N3—Li1103.38 (19)H13A—C13—H13C109.5
C10—N4—C9112.1 (2)H13B—C13—H13C109.5
C10—N4—Si1124.41 (17)N2—C14—H14A109.5
C9—N4—Si1120.94 (18)N2—C14—H14B109.5
C2—C1—Si1134.22 (18)H14A—C14—H14B109.5
C2—C1—Li1102.57 (18)N2—C14—H14C109.5
Si1—C1—Li181.69 (13)H14A—C14—H14C109.5
C2—C1—H1110.4H14B—C14—H14C109.5
Si1—C1—H1110.4N2—C15—C16112.1 (2)
Li1—C1—H1110.4N2—C15—H15A109.2
C3—C2—C7113.4 (2)C16—C15—H15A109.2
C3—C2—C1125.3 (2)N2—C15—H15B109.2
C7—C2—C1121.3 (2)C16—C15—H15B109.2
C4—C3—C2123.2 (2)H15A—C15—H15B107.9
C4—C3—H3118.4N3—C16—C15112.8 (2)
C2—C3—H3118.4N3—C16—H16A109.0
C3—C4—C5121.0 (2)C15—C16—H16A109.0
C3—C4—H4119.5N3—C16—H16B109.0
C5—C4—H4119.5C15—C16—H16B109.0
C6—C5—C4118.2 (2)H16A—C16—H16B107.8
C6—C5—H5120.9N3—C17—H17A109.5
C4—C5—H5120.9N3—C17—H17B109.5
C7—C6—C5120.9 (2)H17A—C17—H17B109.5
C7—C6—H6119.5N3—C17—H17C109.5
C5—C6—H6119.5H17A—C17—H17C109.5
C6—C7—C2123.2 (2)H17B—C17—H17C109.5
C6—C7—H7118.4N3—C18—H18A109.5
C2—C7—H7118.4N3—C18—H18B109.5
Si1—C8—H8A109.5H18A—C18—H18B109.5
Si1—C8—H8B109.5N3—C18—H18C109.5
H8A—C8—H8B109.5H18A—C18—H18C109.5
Si1—C8—H8C109.5H18B—C18—H18C109.5
H8A—C8—H8C109.5
N4—Si1—N1—C1148.96 (19)C1—Si1—N4—C1023.8 (3)
C1—Si1—N1—C1176.78 (19)C8—Si1—N4—C10101.0 (2)
C8—Si1—N1—C11167.13 (18)N1—Si1—N4—C953.8 (2)
N4—Si1—N1—C1289.7 (2)C1—Si1—N4—C9175.9 (2)
C1—Si1—N1—C12144.6 (2)C8—Si1—N4—C959.4 (3)
C8—Si1—N1—C1228.5 (2)N4—Si1—C1—C237.5 (3)
N4—Si1—N1—Li1142.46 (13)N1—Si1—C1—C283.1 (2)
C1—Si1—N1—Li116.73 (14)C8—Si1—C1—C2163.8 (2)
C8—Si1—N1—Li199.36 (14)N4—Si1—C1—Li1136.99 (14)
N2—Li1—N1—C1127.4 (3)N1—Si1—C1—Li116.35 (14)
N3—Li1—N1—C11136.7 (2)C8—Si1—C1—Li196.76 (15)
C1—Li1—N1—C11103.42 (17)N2—Li1—C1—C28.7 (3)
N2—Li1—N1—C1290.8 (3)N3—Li1—C1—C2121.1 (2)
N3—Li1—N1—C1218.5 (3)N1—Li1—C1—C2121.06 (17)
C1—Li1—N1—C12138.4 (2)N2—Li1—C1—Si1142.3 (2)
N2—Li1—N1—Si1143.3 (2)N3—Li1—C1—Si1105.3 (2)
N3—Li1—N1—Si1107.4 (2)N1—Li1—C1—Si112.53 (11)
C1—Li1—N1—Si112.51 (11)Si1—C1—C2—C39.5 (4)
N3—Li1—N2—C14139.5 (2)Li1—C1—C2—C381.0 (3)
N1—Li1—N2—C1415.9 (3)Si1—C1—C2—C7172.07 (19)
C1—Li1—N2—C1493.6 (3)Li1—C1—C2—C797.3 (2)
N3—Li1—N2—C1398.0 (2)C7—C2—C3—C42.3 (3)
N1—Li1—N2—C13138.4 (2)C1—C2—C3—C4176.2 (2)
C1—Li1—N2—C1328.9 (3)C2—C3—C4—C50.2 (4)
N3—Li1—N2—C1518.0 (2)C3—C4—C5—C61.8 (4)
N1—Li1—N2—C15105.6 (2)C4—C5—C6—C71.4 (4)
C1—Li1—N2—C15145.0 (2)C5—C6—C7—C21.0 (4)
N2—Li1—N3—C17129.1 (2)C3—C2—C7—C62.7 (3)
N1—Li1—N3—C17100.6 (3)C1—C2—C7—C6175.8 (2)
C1—Li1—N3—C173.7 (3)C14—N2—C15—C16172.6 (2)
N2—Li1—N3—C18108.6 (2)C13—N2—C15—C1668.7 (3)
N1—Li1—N3—C1821.8 (3)Li1—N2—C15—C1642.1 (3)
C1—Li1—N3—C18118.7 (2)C17—N3—C16—C15157.0 (3)
N2—Li1—N3—C168.1 (2)C18—N3—C16—C1582.3 (3)
N1—Li1—N3—C16138.4 (2)Li1—N3—C16—C1533.9 (3)
C1—Li1—N3—C16124.7 (2)N2—C15—C16—N355.2 (3)
N1—Si1—N4—C10145.9 (2)

Experimental details

Crystal data
Chemical formula[Li(C12H21NSi)(C6H16N2)]
Mr344.55
Crystal system, space groupMonoclinic, P21/c
Temperature (K)183
a, b, c (Å)13.946 (4), 9.805 (2), 17.236 (4)
β (°) 112.523 (3)
V3)2177.0 (9)
Z4
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.40 × 0.30 × 0.20
Data collection
DiffractometerBruker SMART CCD are-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.956, 0.978
No. of measured, independent and
observed [I > 2σ(I)] reflections
8766, 3841, 2779
Rint0.040
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.060, 0.134, 1.00
No. of reflections3841
No. of parameters226
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.32, 0.18

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 1998), SHELXTL.

Selected geometric parameters (Å, º) top
Li1—N22.085 (5)Si1—N41.720 (2)
Li1—N32.104 (4)Si1—N11.783 (2)
Li1—N12.203 (4)Si1—C11.787 (2)
Li1—C12.261 (5)Si1—C81.869 (3)
N2—Li1—N387.48 (17)C1—Si1—C8108.69 (12)
N2—Li1—N1126.2 (2)C11—N1—C12108.9 (2)
N3—Li1—N1118.18 (19)C11—N1—Si1116.35 (16)
N2—Li1—C1127.43 (19)C12—N1—Si1122.83 (17)
N3—Li1—C1120.2 (2)C11—N1—Li196.01 (17)
N1—Li1—C181.60 (15)C12—N1—Li1125.01 (19)
N4—Si1—N1106.83 (11)Si1—N1—Li183.49 (13)
N4—Si1—C1115.45 (10)C2—C1—Si1134.22 (18)
N1—Si1—C1109.59 (10)C2—C1—Li1102.57 (18)
N4—Si1—C8111.60 (12)Si1—C1—Li181.69 (13)
N1—Si1—C8104.05 (11)
 

Subscribe to Acta Crystallographica Section C: Structural Chemistry

The full text of this article is available to subscribers to the journal.

If you have already registered and are using a computer listed in your registration details, please email support@iucr.org for assistance.

Buy online

You may purchase this article in PDF and/or HTML formats. For purchasers in the European Community who do not have a VAT number, VAT will be added at the local rate. Payments to the IUCr are handled by WorldPay, who will accept payment by credit card in several currencies. To purchase the article, please complete the form below (fields marked * are required), and then click on `Continue'.
E-mail address* 
Repeat e-mail address* 
(for error checking) 

Format*   PDF (US $40)
   HTML (US $40)
   PDF+HTML (US $50)
In order for VAT to be shown for your country javascript needs to be enabled.

VAT number 
(non-UK EC countries only) 
Country* 
 

Terms and conditions of use
Contact us

Follow Acta Cryst. C
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds