[(1-tert-Butyl-2-phenyl­vinyl­amino)(di­methyl­amino)­di­methyl­silyl-κ2N,N′] (N,N,N′,N′-tetra­methyl­enedi­amine-κ2N,N′)­lithium(I)

Shi, H.-P.; Liu, D.-S.; Huang, S.-P.

doi:10.1107/S1600536803010353

Buy article online - an online subscription or single-article purchase is required to access this article.

[(1-tert-Butyl-2-phenylvinylamino)(dimethylamino)dimethylsilyl-κ²N,N′] (N,N,N′,N′-tetramethylenediamine-κ²N,N′)lithium(I)

H.-P. Shi, D.-S. Liu and S.-P. Huang

The crystal structure of the title compound, [Li(C₁₆H₂₇N₂Si)(C₆H₁₆N₂)], contains the N—Si—N—Li four-membered heterocycle. The heterocycle contains a planar three-coordinated N-atom centre, a four-coordinated N-atom centre, a four-coordinate Li-atom centre and a four-coordinated Si-atom centre, and adopts a folded conformation. There are two molecules in the asymmetric unit.

Read article Similar articles

Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536803010353/ac6040sup1.cif Contains datablocks global, I
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536803010353/ac6040Isup2.hkl Contains datablock I

CCDC reference: 214781

checkCIF report

Key indicators

Single-crystal X-ray study
T = 178 K
Mean (C-C) = 0.006 Å
R factor = 0.058
wR factor = 0.066
Data-to-parameter ratio = 15.9

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level B:



PLAT_213  Alert B Atom C26     has ADP max/min Ratio ...........       4.60 prolate


 Alert Level C:



PLAT_213  Alert C Atom C27     has ADP max/min Ratio ...........       3.40 prolate

PLAT_213  Alert C Atom C28     has ADP max/min Ratio ...........       3.20 prolate

General Notes



REFLT_03
         From the CIF: _diffrn_reflns_theta_max           25.01
         From the CIF: _reflns_number_total               8386
         Count of symmetry unique reflns         4840
         Completeness (_total/calc)            173.26%
         TEST3: Check Friedels for noncentro structure
         Estimate of Friedel pairs measured      3546
         Fraction of Friedel pairs measured     0.733
         Are heavy atom types Z>Si present          yes
          Please check that the estimate of the number of Friedel pairs is
          correct. If it is not, please give the correct count in the
          _publ_section_exptl_refinement section of the submitted CIF.


 0 Alert Level A = Potentially serious problem

 1 Alert Level B = Potential problem

 2 Alert Level C = Please check

Comment top

There is much current interest in the structures of organolithium compounds. We describe below an organolithium compound that has an unprecedented structure with several unusual features and possesses important potential for synthesis of other novel organometallic compounds.

The novel title compound, (I), containing the N—Si—N—Li fragment, has been characterized by single-crystal X-ray diffraction analysis. The geometric parameters of the moiety of (I) are listed in Table 1 and the molecular structure is illustrated in Fig 1. This compound shows several interesting features, as follows: (i) there is a four-membered ring where two N atoms were bonded to the Li atom; the ring contains a planar N atom (N3 sum of angles 359.9°), a four-coordinate Li center, and a four-coordinate N center, N4. (ii) The four-membered ring adopts a folded conformation. The angle between the Li2/N3/Si2 and Li2/N4/Si2 planes is 14.6°. The angle between the N3/Si2/N4 and N3/Li2/N4 planes is 15.0°. (iii) As a consequence of the coordination of N4 to Li, the Si2—N4 bond length [1.766 (3) Å] is longer than the N3—Si2 bond length [1.649 (3) Å]; in the R₃Si–NR'₂ species, the Si—-N bond lengths fall in the range 1.710–1.721 Å (Lukevics et al., 1985). (iv) The N3—C24 bond length [1.383 (4) Å] is much shorter than the common N—Csp³ bond length, which usually lies in the range 1.45–1.48 Å, and this can be attributed to delocalization of the negative charge either by π–π bonding or more likely to negative conjugation leading to some double-bond character in the N3—C24 bond (Brinkman et al., 1994). It is noteworthy that much novel species should be formed by use of this title compound.

Experimental top

n-Butyllithium (molar ratio 1:1:1) was added dropwise to a solution of toluene and TMEDA (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 N,N-dimethyldimethylchlorosilane (molar ratio 1:1) 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). The mixture was filtered and N,N-dimethyldimethylbenzylsilylamine was isolated by vacuum distillation of the filtrate as a colorless liquid. A solution of LiⁿBu in hexane was slowly added to N,N-dimethyldimethylbenzylsilylamine and TMEDA in pentane (molar ratio 1:1:1) at ambient temperature. The mixture was stirred for 18 h, Bu^tCN (molar ratio 1:1) was added and stirring was continued for a further 4 h. The solution was concentrated and yielded a colorless crystal of the title compound under vacuum. Crystals suitable for a single-crystal X-ray diffraction study 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, and the pentane was distilled from a drying agent with sodium.

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

	Fig. 1. The molecule of (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented by small spheres of arbitrary radii.
	Fig. 2. A packing diagram of the title molecule, viewed along the a axis. For clarity, all H atoms have been omitted.

[(1-tert-Butyl-2-phenylvinylamino)(dimethylamino)dimethylsilyl-κ²N,N'] (N,N,N',N'-tetramethylenediamine-κ²N,N')lithium(I) top

Crystal data top

[Li(C₁₆H₂₇N₂Si)(C₆H₁₆N₂)]	F(000) = 880
M_r = 398.63	D_x = 1.028 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71073 Å
a = 14.819 (3) Å	Cell parameters from 1711 reflections
b = 9.4142 (16) Å	θ = 2.4–18.0°
c = 18.635 (3) Å	µ = 0.10 mm⁻¹
β = 97.674 (3)°	T = 178 K
V = 2576.4 (8) Å³	Block, colorless
Z = 4	0.40 × 0.30 × 0.30 mm

Data collection top

Bruker CCD area-detector diffractometer	8386 independent reflections
Radiation source: oil sealed	4772 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.043
ω scans	θ_max = 25.0°, θ_min = 1.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −17→16
T_min = 0.960, T_max = 0.969	k = −11→11
10666 measured reflections	l = −18→22

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.058	H-atom parameters constrained
wR(F²) = 0.066	w = 1/[σ²(F_o²) + (0.0005P)²] where P = (F_o² + 2F_c²)/3
S = 0.83	(Δ/σ)_max < 0.001
8386 reflections	Δρ_max = 0.34 e Å⁻³
527 parameters	Δρ_min = −0.25 e Å⁻³
1 restraint	Absolute structure: Flack (1983)
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.05 (11)

Crystal data top

[Li(C₁₆H₂₇N₂Si)(C₆H₁₆N₂)]	V = 2576.4 (8) Å³
M_r = 398.63	Z = 4
Monoclinic, P2₁	Mo Kα radiation
a = 14.819 (3) Å	µ = 0.10 mm⁻¹
b = 9.4142 (16) Å	T = 178 K
c = 18.635 (3) Å	0.40 × 0.30 × 0.30 mm
β = 97.674 (3)°

Data collection top

Bruker CCD area-detector diffractometer	8386 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	4772 reflections with I > 2σ(I)
T_min = 0.960, T_max = 0.969	R_int = 0.043
10666 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.058	H-atom parameters constrained
wR(F²) = 0.066	Δρ_max = 0.34 e Å⁻³
S = 0.83	Δρ_min = −0.25 e Å⁻³
8386 reflections	Absolute structure: Flack (1983)
527 parameters	Absolute structure parameter: 0.05 (11)
1 restraint

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

	x	y	z	U_iso*/U_eq
Li1	0.2004 (4)	0.2342 (7)	0.2651 (3)	0.0437 (18)
Li2	0.6702 (5)	0.5323 (7)	0.2263 (4)	0.0463 (19)
Si1	0.16518 (8)	0.38917 (12)	0.37918 (5)	0.0365 (3)
Si2	0.61781 (8)	0.69132 (11)	0.10769 (6)	0.0400 (3)
N1	0.18673 (19)	0.2189 (3)	0.37029 (13)	0.0302 (8)
N2	0.2199 (2)	0.4647 (3)	0.30983 (16)	0.0404 (9)
N3	0.7173 (2)	0.6236 (3)	0.14095 (14)	0.0322 (8)
N4	0.5430 (2)	0.6025 (3)	0.15889 (15)	0.0404 (9)
N5	0.1145 (2)	0.2461 (3)	0.16363 (15)	0.0458 (9)
N6	0.2835 (2)	0.0980 (3)	0.21143 (16)	0.0436 (9)
N7	0.6742 (3)	0.5756 (4)	0.33954 (17)	0.0540 (10)
N8	0.7140 (2)	0.3240 (3)	0.26068 (17)	0.0463 (9)
C1	0.3473 (3)	0.0256 (4)	0.42463 (19)	0.0379 (11)
C2	0.3865 (3)	0.1577 (4)	0.43098 (18)	0.0407 (11)
H2	0.3500	0.2371	0.4343	0.049*
C3	0.4789 (3)	0.1748 (5)	0.4325 (2)	0.0545 (12)
H3	0.5035	0.2657	0.4365	0.065*
C4	0.5352 (3)	0.0614 (5)	0.4284 (2)	0.0667 (15)
H4	0.5974	0.0737	0.4280	0.080*
C5	0.4968 (3)	−0.0715 (5)	0.4247 (2)	0.0699 (15)
H5	0.5341	−0.1507	0.4235	0.084*
C6	0.4047 (3)	−0.0901 (5)	0.4228 (2)	0.0609 (13)
H6	0.3805	−0.1814	0.4202	0.073*
C7	0.2490 (3)	0.0004 (4)	0.42309 (16)	0.0346 (11)
H7	0.2330	−0.0890	0.4385	0.042*
C8	0.1783 (3)	0.0902 (4)	0.40210 (17)	0.0297 (10)
C9	0.0803 (3)	0.0392 (4)	0.4110 (2)	0.0399 (11)
C10	0.0728 (3)	−0.1177 (4)	0.43058 (19)	0.0603 (13)
H10A	0.1054	−0.1344	0.4779	0.090*
H10B	0.0982	−0.1750	0.3957	0.090*
H10C	0.0098	−0.1421	0.4305	0.090*
C11	0.0487 (2)	0.1253 (4)	0.47231 (18)	0.0538 (12)
H11A	0.0870	0.1046	0.5168	0.081*
H11B	−0.0131	0.1006	0.4770	0.081*
H11C	0.0522	0.2247	0.4617	0.081*
C12	0.0158 (2)	0.0639 (4)	0.34123 (18)	0.0516 (12)
H12A	−0.0451	0.0395	0.3488	0.077*
H12B	0.0340	0.0055	0.3034	0.077*
H12C	0.0179	0.1620	0.3276	0.077*
C13	0.2112 (2)	0.4694 (4)	0.46952 (16)	0.0526 (12)
H13A	0.1795	0.4301	0.5066	0.079*
H13B	0.2027	0.5704	0.4676	0.079*
H13C	0.2750	0.4484	0.4803	0.079*
C14	0.0453 (2)	0.4555 (4)	0.35867 (18)	0.0500 (12)
H14A	0.0221	0.4342	0.3092	0.075*
H14B	0.0442	0.5563	0.3661	0.075*
H14C	0.0080	0.4098	0.3902	0.075*
C15	0.3195 (3)	0.4543 (4)	0.31790 (19)	0.0618 (14)
H15A	0.3402	0.4723	0.2721	0.093*
H15B	0.3379	0.3607	0.3342	0.093*
H15C	0.3456	0.5231	0.3527	0.093*
C16	0.1942 (3)	0.6088 (4)	0.28296 (19)	0.0595 (14)
H16A	0.2181	0.6778	0.3184	0.089*
H16B	0.1291	0.6165	0.2744	0.089*
H16C	0.2188	0.6256	0.2386	0.089*
C17	0.8072 (3)	0.4138 (4)	0.04034 (18)	0.0330 (10)
C18	0.8606 (3)	0.3436 (4)	−0.00472 (19)	0.0440 (12)
H18	0.9179	0.3799	−0.0096	0.053*
C19	0.8313 (3)	0.2214 (4)	−0.0426 (2)	0.0519 (12)
H19	0.8684	0.1789	−0.0729	0.062*
C20	0.7486 (3)	0.1631 (4)	−0.0358 (2)	0.0598 (13)
H20	0.7294	0.0801	−0.0603	0.072*
C21	0.6940 (3)	0.2298 (4)	0.0082 (2)	0.0549 (13)
H21	0.6369	0.1926	0.0124	0.066*
C22	0.7229 (3)	0.3508 (4)	0.04592 (19)	0.0456 (12)
H22	0.6851	0.3919	0.0761	0.055*
C23	0.8421 (2)	0.5402 (4)	0.07857 (18)	0.0359 (10)
H23	0.9016	0.5624	0.0722	0.043*
C24	0.8042 (3)	0.6326 (4)	0.12200 (19)	0.0347 (10)
C25	0.8638 (3)	0.7587 (4)	0.1545 (2)	0.0473 (12)
C26	0.8430 (4)	0.7981 (7)	0.2253 (3)	0.199 (4)
H26A	0.8628	0.7243	0.2593	0.298*
H26B	0.7784	0.8113	0.2235	0.298*
H26C	0.8738	0.8850	0.2403	0.298*
C27	0.8404 (4)	0.8865 (5)	0.1046 (3)	0.170 (3)
H27A	0.7788	0.8782	0.0814	0.255*
H27B	0.8809	0.8889	0.0684	0.255*
H27C	0.8470	0.9724	0.1325	0.255*
C28	0.9637 (3)	0.7409 (5)	0.1573 (3)	0.129 (2)
H28A	0.9941	0.8244	0.1780	0.194*
H28B	0.9786	0.7270	0.1092	0.194*
H28C	0.9832	0.6598	0.1866	0.194*
C29	0.5846 (3)	0.6635 (5)	0.00799 (17)	0.0780 (16)
H29A	0.6284	0.7084	−0.0181	0.117*
H29B	0.5256	0.7042	−0.0066	0.117*
H29C	0.5827	0.5636	−0.0024	0.117*
C30	0.5955 (3)	0.8849 (4)	0.1215 (2)	0.0798 (15)
H30A	0.6126	0.9089	0.1716	0.120*
H30B	0.5319	0.9043	0.1080	0.120*
H30C	0.6306	0.9406	0.0921	0.120*
C31	0.5038 (3)	0.4692 (4)	0.1281 (2)	0.0647 (14)
H31A	0.4553	0.4900	0.0901	0.097*
H31B	0.4805	0.4152	0.1653	0.097*
H31C	0.5501	0.4154	0.1088	0.097*
C32	0.4702 (3)	0.6857 (4)	0.18646 (19)	0.0642 (13)
H32A	0.4270	0.7167	0.1465	0.096*
H32B	0.4964	0.7669	0.2126	0.096*
H32C	0.4400	0.6275	0.2182	0.096*
C33	0.1314 (3)	0.3859 (4)	0.13395 (19)	0.0730 (15)
H33A	0.1959	0.4017	0.1374	0.109*
H33B	0.1046	0.4579	0.1609	0.109*
H33C	0.1050	0.3900	0.0841	0.109*
C34	0.0135 (3)	0.2265 (5)	0.16079 (18)	0.0692 (14)
H34A	−0.0145	0.2277	0.1113	0.104*
H34B	−0.0110	0.3021	0.1869	0.104*
H34C	0.0015	0.1371	0.1824	0.104*
C35	0.1476 (3)	0.1322 (4)	0.12019 (19)	0.0597 (14)
H35A	0.1288	0.1510	0.0692	0.072*
H35B	0.1209	0.0425	0.1321	0.072*
C36	0.2516 (3)	0.1214 (4)	0.1346 (2)	0.0586 (13)
H36A	0.2717	0.0435	0.1066	0.070*
H36B	0.2781	0.2082	0.1189	0.070*
C37	0.3823 (3)	0.1157 (4)	0.22378 (19)	0.0651 (14)
H37A	0.4103	0.0459	0.1964	0.098*
H37B	0.4037	0.1038	0.2744	0.098*
H37C	0.3979	0.2091	0.2087	0.098*
C38	0.2609 (3)	−0.0468 (4)	0.23303 (19)	0.0637 (14)
H38A	0.1961	−0.0558	0.2309	0.096*
H38B	0.2893	−0.0647	0.2816	0.096*
H38C	0.2827	−0.1142	0.2007	0.096*
C39	0.7040 (3)	0.7147 (5)	0.3694 (2)	0.0867 (17)
H39A	0.6982	0.7172	0.4201	0.130*
H39B	0.6667	0.7877	0.3447	0.130*
H39C	0.7664	0.7301	0.3629	0.130*
C40	0.5804 (3)	0.5531 (4)	0.35499 (19)	0.0681 (14)
H40A	0.5551	0.4710	0.3291	0.102*
H40B	0.5442	0.6350	0.3399	0.102*
H40C	0.5808	0.5385	0.4060	0.102*
C41	0.7354 (3)	0.4653 (6)	0.3731 (2)	0.0784 (17)
H41A	0.7302	0.4605	0.4244	0.094*
H41B	0.7977	0.4904	0.3681	0.094*
C42	0.7136 (3)	0.3209 (5)	0.3392 (2)	0.0822 (17)
H42A	0.7582	0.2523	0.3605	0.099*
H42B	0.6542	0.2903	0.3496	0.099*
C43	0.6686 (3)	0.1982 (4)	0.2284 (2)	0.0762 (15)
H43A	0.6689	0.2003	0.1769	0.114*
H43B	0.6069	0.1961	0.2389	0.114*
H43C	0.7001	0.1149	0.2481	0.114*
C44	0.8084 (3)	0.3267 (4)	0.24340 (19)	0.0610 (14)
H44A	0.8402	0.2437	0.2632	0.092*
H44B	0.8387	0.4102	0.2640	0.092*
H44C	0.8076	0.3278	0.1918	0.092*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Li1	0.048 (5)	0.037 (4)	0.050 (4)	−0.004 (4)	0.016 (4)	0.004 (3)
Li2	0.042 (5)	0.040 (4)	0.055 (5)	0.001 (4)	0.001 (4)	−0.006 (4)
Si1	0.0368 (7)	0.0327 (7)	0.0406 (7)	−0.0008 (6)	0.0073 (6)	−0.0030 (6)
Si2	0.0365 (8)	0.0409 (8)	0.0433 (7)	0.0014 (6)	0.0085 (6)	0.0065 (6)
N1	0.036 (2)	0.031 (2)	0.0262 (18)	0.0012 (17)	0.0114 (15)	0.0031 (15)
N2	0.038 (2)	0.035 (2)	0.051 (2)	−0.0037 (18)	0.0133 (19)	0.0106 (17)
N3	0.025 (2)	0.0361 (19)	0.037 (2)	−0.0020 (16)	0.0097 (17)	−0.0002 (16)
N4	0.034 (2)	0.042 (2)	0.048 (2)	−0.0025 (18)	0.0156 (18)	0.0018 (18)
N5	0.065 (3)	0.039 (2)	0.035 (2)	0.001 (2)	0.009 (2)	−0.0025 (18)
N6	0.053 (3)	0.045 (2)	0.037 (2)	0.001 (2)	0.0201 (19)	−0.0009 (18)
N7	0.057 (3)	0.068 (3)	0.039 (2)	−0.008 (2)	0.014 (2)	−0.006 (2)
N8	0.047 (3)	0.045 (2)	0.049 (2)	0.002 (2)	0.012 (2)	0.0019 (18)
C1	0.043 (3)	0.035 (3)	0.037 (3)	0.006 (2)	0.010 (2)	−0.001 (2)
C2	0.038 (3)	0.044 (3)	0.042 (3)	0.013 (2)	0.009 (2)	0.004 (2)
C3	0.048 (3)	0.054 (3)	0.060 (3)	0.001 (3)	0.003 (3)	0.005 (3)
C4	0.046 (3)	0.081 (4)	0.073 (4)	0.015 (3)	0.011 (3)	0.019 (3)
C5	0.053 (4)	0.066 (4)	0.093 (4)	0.033 (3)	0.020 (3)	0.010 (3)
C6	0.062 (4)	0.049 (3)	0.072 (3)	0.011 (3)	0.012 (3)	0.006 (3)
C7	0.053 (3)	0.025 (2)	0.029 (2)	0.001 (2)	0.012 (2)	0.0088 (18)
C8	0.043 (3)	0.028 (2)	0.020 (2)	−0.005 (2)	0.012 (2)	−0.0034 (18)
C9	0.045 (3)	0.030 (2)	0.048 (3)	−0.005 (2)	0.017 (2)	0.001 (2)
C10	0.071 (3)	0.039 (3)	0.079 (3)	−0.013 (3)	0.037 (3)	0.006 (3)
C11	0.047 (3)	0.057 (3)	0.062 (3)	−0.004 (2)	0.023 (2)	0.003 (2)
C12	0.041 (3)	0.062 (3)	0.052 (3)	−0.012 (2)	0.010 (2)	−0.006 (2)
C13	0.052 (3)	0.045 (3)	0.062 (3)	0.002 (2)	0.008 (2)	−0.006 (2)
C14	0.045 (3)	0.043 (3)	0.064 (3)	0.010 (2)	0.014 (2)	−0.009 (2)
C15	0.064 (4)	0.059 (3)	0.069 (3)	−0.006 (3)	0.032 (3)	0.013 (3)
C16	0.081 (4)	0.033 (3)	0.066 (3)	−0.004 (3)	0.016 (3)	0.012 (2)
C17	0.031 (3)	0.039 (3)	0.031 (2)	0.005 (2)	0.007 (2)	0.006 (2)
C18	0.044 (3)	0.044 (3)	0.047 (3)	0.007 (2)	0.014 (2)	0.001 (2)
C19	0.054 (3)	0.050 (3)	0.055 (3)	0.010 (3)	0.022 (3)	−0.013 (2)
C20	0.055 (3)	0.051 (3)	0.073 (3)	0.004 (3)	0.008 (3)	−0.022 (3)
C21	0.044 (3)	0.053 (3)	0.069 (3)	−0.007 (3)	0.013 (3)	−0.018 (3)
C22	0.050 (3)	0.044 (3)	0.044 (3)	−0.001 (2)	0.013 (2)	−0.016 (2)
C23	0.026 (3)	0.044 (3)	0.040 (2)	−0.006 (2)	0.012 (2)	−0.003 (2)
C24	0.036 (3)	0.033 (2)	0.033 (2)	0.003 (2)	−0.003 (2)	0.002 (2)
C25	0.038 (3)	0.042 (3)	0.063 (3)	−0.012 (2)	0.010 (2)	−0.009 (2)
C26	0.166 (7)	0.318 (10)	0.133 (5)	−0.179 (7)	0.097 (5)	−0.175 (6)
C27	0.164 (7)	0.060 (4)	0.260 (8)	−0.064 (5)	−0.062 (6)	0.040 (5)
C28	0.034 (3)	0.119 (5)	0.235 (7)	−0.019 (4)	0.015 (4)	−0.100 (5)
C29	0.054 (3)	0.142 (5)	0.038 (3)	0.016 (3)	0.007 (2)	0.014 (3)
C30	0.056 (3)	0.036 (3)	0.151 (4)	0.015 (3)	0.025 (3)	0.022 (3)
C31	0.050 (3)	0.054 (3)	0.093 (4)	−0.004 (3)	0.019 (3)	0.000 (3)
C32	0.050 (3)	0.084 (4)	0.064 (3)	0.006 (3)	0.029 (3)	0.002 (3)
C33	0.110 (4)	0.047 (3)	0.062 (3)	0.000 (3)	0.010 (3)	0.015 (3)
C34	0.063 (4)	0.092 (4)	0.050 (3)	0.003 (3)	−0.002 (3)	0.009 (3)
C35	0.096 (4)	0.050 (3)	0.033 (3)	−0.001 (3)	0.007 (3)	0.008 (2)
C36	0.088 (4)	0.050 (3)	0.046 (3)	0.001 (3)	0.039 (3)	−0.007 (2)
C37	0.059 (4)	0.060 (3)	0.083 (4)	−0.001 (3)	0.034 (3)	−0.007 (3)
C38	0.084 (4)	0.052 (3)	0.060 (3)	0.001 (3)	0.024 (3)	0.001 (2)
C39	0.098 (4)	0.096 (4)	0.071 (3)	−0.026 (4)	0.031 (3)	−0.035 (3)
C40	0.074 (4)	0.084 (4)	0.048 (3)	−0.009 (3)	0.015 (3)	−0.003 (3)
C41	0.080 (4)	0.122 (5)	0.033 (3)	0.021 (4)	0.004 (3)	0.007 (3)
C42	0.094 (5)	0.096 (5)	0.062 (4)	0.019 (4)	0.026 (3)	0.022 (3)
C43	0.079 (4)	0.052 (3)	0.097 (4)	−0.012 (3)	0.009 (3)	−0.003 (3)
C44	0.066 (4)	0.068 (4)	0.048 (3)	0.022 (3)	0.007 (3)	0.010 (2)

Geometric parameters (Å, º) top

Li1—N1	2.003 (6)	C17—C18	1.396 (4)
Li1—N6	2.119 (7)	C17—C22	1.399 (5)
Li1—N5	2.137 (7)	C17—C23	1.446 (4)
Li1—N2	2.328 (7)	C18—C19	1.388 (4)
Li2—N3	2.013 (7)	C18—H18	0.9300
Li2—N7	2.143 (7)	C19—C20	1.364 (5)
Li2—N8	2.137 (7)	C19—H19	0.9300
Li2—N4	2.220 (7)	C20—C21	1.377 (5)
Si1—N1	1.647 (3)	C20—H20	0.9300
Si1—N2	1.764 (3)	C21—C22	1.376 (4)
Si1—C14	1.874 (4)	C21—H21	0.9300
Si1—C13	1.888 (3)	C22—H22	0.9300
Si2—N3	1.649 (3)	C23—C24	1.359 (4)
Si2—N4	1.766 (3)	C23—H23	0.9300
Si2—C29	1.876 (3)	C24—C25	1.553 (5)
Si2—C30	1.876 (4)	C25—C26	1.443 (5)
N1—C8	1.361 (4)	C25—C28	1.485 (5)
N2—C15	1.467 (4)	C25—C27	1.532 (6)
N2—C16	1.477 (4)	C26—H26A	0.9600
N3—C24	1.383 (4)	C26—H26B	0.9600
N4—C31	1.467 (4)	C26—H26C	0.9600
N4—C32	1.480 (4)	C27—H27A	0.9600
N5—C33	1.462 (4)	C27—H27B	0.9600
N5—C35	1.467 (4)	C27—H27C	0.9600
N5—C34	1.502 (4)	C28—H28A	0.9600
N6—C37	1.461 (4)	C28—H28B	0.9600
N6—C36	1.463 (4)	C28—H28C	0.9600
N6—C38	1.473 (4)	C29—H29A	0.9600
N7—C41	1.463 (5)	C29—H29B	0.9600
N7—C40	1.472 (5)	C29—H29C	0.9600
N7—C39	1.467 (5)	C30—H30A	0.9600
N8—C43	1.452 (4)	C30—H30B	0.9600
N8—C42	1.464 (4)	C30—H30C	0.9600
N8—C44	1.477 (4)	C31—H31A	0.9600
C1—C2	1.371 (5)	C31—H31B	0.9600
C1—C6	1.386 (5)	C31—H31C	0.9600
C1—C7	1.472 (5)	C32—H32A	0.9600
C2—C3	1.374 (5)	C32—H32B	0.9600
C2—H2	0.9300	C32—H32C	0.9600
C3—C4	1.363 (5)	C33—H33A	0.9600
C3—H3	0.9300	C33—H33B	0.9600
C4—C5	1.372 (6)	C33—H33C	0.9600
C4—H4	0.9300	C34—H34A	0.9600
C5—C6	1.372 (5)	C34—H34B	0.9600
C5—H5	0.9300	C34—H34C	0.9600
C6—H6	0.9300	C35—C36	1.532 (5)
C7—C8	1.362 (4)	C35—H35A	0.9700
C7—H7	0.9300	C35—H35B	0.9700
C8—C9	1.559 (5)	C36—H36A	0.9700
C9—C11	1.525 (4)	C36—H36B	0.9700
C9—C12	1.526 (4)	C37—H37A	0.9600
C9—C10	1.529 (4)	C37—H37B	0.9600
C10—H10A	0.9600	C37—H37C	0.9600
C10—H10B	0.9600	C38—H38A	0.9600
C10—H10C	0.9600	C38—H38B	0.9600
C11—H11A	0.9600	C38—H38C	0.9600
C11—H11B	0.9600	C39—H39A	0.9600
C11—H11C	0.9600	C39—H39B	0.9600
C12—H12A	0.9600	C39—H39C	0.9600
C12—H12B	0.9600	C40—H40A	0.9600
C12—H12C	0.9600	C40—H40B	0.9600
C13—H13A	0.9600	C40—H40C	0.9600
C13—H13B	0.9600	C41—C42	1.516 (5)
C13—H13C	0.9600	C41—H41A	0.9700
C14—H14A	0.9600	C41—H41B	0.9700
C14—H14B	0.9600	C42—H42A	0.9700
C14—H14C	0.9600	C42—H42B	0.9700
C15—H15A	0.9600	C43—H43A	0.9600
C15—H15B	0.9600	C43—H43B	0.9600
C15—H15C	0.9600	C43—H43C	0.9600
C16—H16A	0.9600	C44—H44A	0.9600
C16—H16B	0.9600	C44—H44B	0.9600
C16—H16C	0.9600	C44—H44C	0.9600

N1—Li1—N6	124.0 (3)	C19—C18—C17	122.3 (4)
N1—Li1—N5	138.0 (4)	C19—C18—H18	118.9
N6—Li1—N5	85.9 (3)	C17—C18—H18	118.9
N1—Li1—N2	75.0 (2)	C20—C19—C18	120.7 (4)
N6—Li1—N2	132.9 (3)	C20—C19—H19	119.6
N5—Li1—N2	107.4 (3)	C18—C19—H19	119.6
N3—Li2—N7	136.9 (4)	C19—C20—C21	118.5 (4)
N3—Li2—N8	120.4 (4)	C19—C20—H20	120.8
N7—Li2—N8	84.9 (3)	C21—C20—H20	120.8
N3—Li2—N4	77.5 (2)	C22—C21—C20	121.0 (4)
N7—Li2—N4	114.2 (3)	C22—C21—H21	119.5
N8—Li2—N4	130.1 (3)	C20—C21—H21	119.5
N1—Si1—N2	101.80 (15)	C21—C22—C17	122.2 (4)
N1—Si1—C14	119.66 (16)	C21—C22—H22	118.9
N2—Si1—C14	103.43 (16)	C17—C22—H22	118.9
N1—Si1—C13	115.28 (15)	C24—C23—C17	132.1 (4)
N2—Si1—C13	110.19 (16)	C24—C23—H23	113.9
C14—Si1—C13	105.59 (16)	C17—C23—H23	113.9
N3—Si2—N4	101.99 (15)	C23—C24—N3	125.8 (4)
N3—Si2—C29	114.94 (16)	C23—C24—C25	117.6 (4)
N4—Si2—C29	111.60 (17)	N3—C24—C25	116.5 (3)
N3—Si2—C30	119.26 (17)	C26—C25—C28	109.3 (4)
N4—Si2—C30	104.52 (18)	C26—C25—C27	107.2 (4)
C29—Si2—C30	104.14 (19)	C28—C25—C27	104.7 (4)
C8—N1—Si1	142.4 (2)	C26—C25—C24	111.9 (4)
C8—N1—Li1	121.2 (3)	C28—C25—C24	116.1 (4)
Si1—N1—Li1	94.3 (2)	C27—C25—C24	107.1 (3)
C15—N2—C16	107.8 (3)	C25—C26—H26A	109.5
C15—N2—Si1	116.9 (2)	C25—C26—H26B	109.5
C16—N2—Si1	119.7 (3)	H26A—C26—H26B	109.5
C15—N2—Li1	92.8 (3)	C25—C26—H26C	109.5
C16—N2—Li1	136.1 (3)	H26A—C26—H26C	109.5
Si1—N2—Li1	80.77 (19)	H26B—C26—H26C	109.5
C24—N3—Si2	134.2 (3)	C25—C27—H27A	109.5
C24—N3—Li2	131.4 (3)	C25—C27—H27B	109.5
Si2—N3—Li2	94.3 (2)	H27A—C27—H27B	109.5
C31—N4—C32	108.6 (3)	C25—C27—H27C	109.5
C31—N4—Si2	116.0 (2)	H27A—C27—H27C	109.5
C32—N4—Si2	118.4 (3)	H27B—C27—H27C	109.5
C31—N4—Li2	103.2 (3)	C25—C28—H28A	109.5
C32—N4—Li2	124.3 (3)	C25—C28—H28B	109.5
Si2—N4—Li2	84.3 (2)	H28A—C28—H28B	109.5
C33—N5—C35	111.2 (3)	C25—C28—H28C	109.5
C33—N5—C34	108.6 (3)	H28A—C28—H28C	109.5
C35—N5—C34	107.2 (3)	H28B—C28—H28C	109.5
C33—N5—Li1	105.6 (3)	Si2—C29—H29A	109.5
C35—N5—Li1	104.3 (3)	Si2—C29—H29B	109.5
C34—N5—Li1	119.9 (3)	H29A—C29—H29B	109.5
C37—N6—C36	108.9 (3)	Si2—C29—H29C	109.5
C37—N6—C38	108.8 (3)	H29A—C29—H29C	109.5
C36—N6—C38	110.5 (3)	H29B—C29—H29C	109.5
C37—N6—Li1	119.3 (3)	Si2—C30—H30A	109.5
C36—N6—Li1	103.8 (3)	Si2—C30—H30B	109.5
C38—N6—Li1	105.3 (3)	H30A—C30—H30B	109.5
C41—N7—C40	111.2 (4)	Si2—C30—H30C	109.5
C41—N7—C39	109.5 (4)	H30A—C30—H30C	109.5
C40—N7—C39	107.4 (3)	H30B—C30—H30C	109.5
C41—N7—Li2	102.8 (3)	N4—C31—H31A	109.5
C40—N7—Li2	105.2 (3)	N4—C31—H31B	109.5
C39—N7—Li2	120.7 (3)	H31A—C31—H31B	109.5
C43—N8—C42	109.5 (3)	N4—C31—H31C	109.5
C43—N8—C44	108.8 (3)	H31A—C31—H31C	109.5
C42—N8—C44	110.4 (3)	H31B—C31—H31C	109.5
C43—N8—Li2	121.3 (3)	N4—C32—H32A	109.5
C42—N8—Li2	106.1 (3)	N4—C32—H32B	109.5
C44—N8—Li2	100.2 (3)	H32A—C32—H32B	109.5
C2—C1—C6	117.5 (4)	N4—C32—H32C	109.5
C2—C1—C7	123.7 (4)	H32A—C32—H32C	109.5
C6—C1—C7	118.8 (4)	H32B—C32—H32C	109.5
C3—C2—C1	121.1 (4)	N5—C33—H33A	109.5
C3—C2—H2	119.4	N5—C33—H33B	109.5
C1—C2—H2	119.4	H33A—C33—H33B	109.5
C4—C3—C2	121.5 (4)	N5—C33—H33C	109.5
C4—C3—H3	119.2	H33A—C33—H33C	109.5
C2—C3—H3	119.2	H33B—C33—H33C	109.5
C3—C4—C5	117.6 (4)	N5—C34—H34A	109.5
C3—C4—H4	121.2	N5—C34—H34B	109.5
C5—C4—H4	121.2	H34A—C34—H34B	109.5
C6—C5—C4	121.5 (4)	N5—C34—H34C	109.5
C6—C5—H5	119.3	H34A—C34—H34C	109.5
C4—C5—H5	119.3	H34B—C34—H34C	109.5
C5—C6—C1	120.7 (4)	N5—C35—C36	110.8 (3)
C5—C6—H6	119.7	N5—C35—H35A	109.5
C1—C6—H6	119.7	C36—C35—H35A	109.5
C8—C7—C1	128.8 (4)	N5—C35—H35B	109.5
C8—C7—H7	115.6	C36—C35—H35B	109.5
C1—C7—H7	115.6	H35A—C35—H35B	108.1
C7—C8—N1	124.5 (4)	N6—C36—C35	111.6 (3)
C7—C8—C9	118.0 (3)	N6—C36—H36A	109.3
N1—C8—C9	117.4 (3)	C35—C36—H36A	109.3
C11—C9—C12	109.7 (3)	N6—C36—H36B	109.3
C11—C9—C10	107.1 (3)	C35—C36—H36B	109.3
C12—C9—C10	107.0 (3)	H36A—C36—H36B	108.0
C11—C9—C8	107.5 (3)	N6—C37—H37A	109.5
C12—C9—C8	110.4 (3)	N6—C37—H37B	109.5
C10—C9—C8	115.0 (3)	H37A—C37—H37B	109.5
C9—C10—H10A	109.5	N6—C37—H37C	109.5
C9—C10—H10B	109.5	H37A—C37—H37C	109.5
H10A—C10—H10B	109.5	H37B—C37—H37C	109.5
C9—C10—H10C	109.5	N6—C38—H38A	109.5
H10A—C10—H10C	109.5	N6—C38—H38B	109.5
H10B—C10—H10C	109.5	H38A—C38—H38B	109.5
C9—C11—H11A	109.5	N6—C38—H38C	109.5
C9—C11—H11B	109.5	H38A—C38—H38C	109.5
H11A—C11—H11B	109.5	H38B—C38—H38C	109.5
C9—C11—H11C	109.5	N7—C39—H39A	109.5
H11A—C11—H11C	109.5	N7—C39—H39B	109.5
H11B—C11—H11C	109.5	H39A—C39—H39B	109.5
C9—C12—H12A	109.5	N7—C39—H39C	109.5
C9—C12—H12B	109.5	H39A—C39—H39C	109.5
H12A—C12—H12B	109.5	H39B—C39—H39C	109.5
C9—C12—H12C	109.5	N7—C40—H40A	109.5
H12A—C12—H12C	109.5	N7—C40—H40B	109.5
H12B—C12—H12C	109.5	H40A—C40—H40B	109.5
Si1—C13—H13A	109.5	N7—C40—H40C	109.5
Si1—C13—H13B	109.5	H40A—C40—H40C	109.5
H13A—C13—H13B	109.5	H40B—C40—H40C	109.5
Si1—C13—H13C	109.5	N7—C41—C42	111.9 (4)
H13A—C13—H13C	109.5	N7—C41—H41A	109.2
H13B—C13—H13C	109.5	C42—C41—H41A	109.2
Si1—C14—H14A	109.5	N7—C41—H41B	109.2
Si1—C14—H14B	109.5	C42—C41—H41B	109.2
H14A—C14—H14B	109.5	H41A—C41—H41B	107.9
Si1—C14—H14C	109.5	N8—C42—C41	111.7 (4)
H14A—C14—H14C	109.5	N8—C42—H42A	109.3
H14B—C14—H14C	109.5	C41—C42—H42A	109.3
N2—C15—H15A	109.5	N8—C42—H42B	109.3
N2—C15—H15B	109.5	C41—C42—H42B	109.3
H15A—C15—H15B	109.5	H42A—C42—H42B	107.9
N2—C15—H15C	109.5	N8—C43—H43A	109.5
H15A—C15—H15C	109.5	N8—C43—H43B	109.5
H15B—C15—H15C	109.5	H43A—C43—H43B	109.5
N2—C16—H16A	109.5	N8—C43—H43C	109.5
N2—C16—H16B	109.5	H43A—C43—H43C	109.5
H16A—C16—H16B	109.5	H43B—C43—H43C	109.5
N2—C16—H16C	109.5	N8—C44—H44A	109.5
H16A—C16—H16C	109.5	N8—C44—H44B	109.5
H16B—C16—H16C	109.5	H44A—C44—H44B	109.5
C18—C17—C22	115.3 (4)	N8—C44—H44C	109.5
C18—C17—C23	119.4 (4)	H44A—C44—H44C	109.5
C22—C17—C23	125.2 (4)	H44B—C44—H44C	109.5

Experimental details

Crystal data
Chemical formula	[Li(C₁₆H₂₇N₂Si)(C₆H₁₆N₂)]
M_r	398.63
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	178
a, b, c (Å)	14.819 (3), 9.4142 (16), 18.635 (3)
β (°)	97.674 (3)
V (Å³)	2576.4 (8)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.40 × 0.30 × 0.30

Data collection
Diffractometer	Bruker CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.960, 0.969
No. of measured, independent and observed [I > 2σ(I)] reflections	10666, 8386, 4772
R_int	0.043
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.058, 0.066, 0.83
No. of reflections	8386
No. of parameters	527
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.34, −0.25
Absolute structure	Flack (1983)
Absolute structure parameter	0.05 (11)

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

Li2—N3	2.013 (7)	Si2—C29	1.876 (3)
Li2—N7	2.143 (7)	Si2—C30	1.876 (4)
Li2—N8	2.137 (7)	N3—C24	1.383 (4)
Li2—N4	2.220 (7)	N4—C31	1.467 (4)
Si2—N3	1.649 (3)	N4—C32	1.480 (4)
Si2—N4	1.766 (3)

N3—Li2—N7	136.9 (4)	C24—N3—Li2	131.4 (3)
N3—Li2—N8	120.4 (4)	Si2—N3—Li2	94.3 (2)
N7—Li2—N8	84.9 (3)	C31—N4—C32	108.6 (3)
N3—Li2—N4	77.5 (2)	C31—N4—Si2	116.0 (2)
N7—Li2—N4	114.2 (3)	C32—N4—Si2	118.4 (3)
N8—Li2—N4	130.1 (3)	C31—N4—Li2	103.2 (3)
N3—Si2—N4	101.99 (15)	C32—N4—Li2	124.3 (3)
N3—Si2—C29	114.94 (16)	Si2—N4—Li2	84.3 (2)
N4—Si2—C29	111.60 (17)	C24—C23—C17	132.1 (4)
N3—Si2—C30	119.26 (17)	C23—C24—N3	125.8 (4)
N4—Si2—C30	104.52 (18)	C23—C24—C25	117.6 (4)
C29—Si2—C30	104.14 (19)	N3—C24—C25	116.5 (3)
C24—N3—Si2	134.2 (3)

Subscribe to Acta Crystallographica Section E: Crystallographic Communications

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

Format		BIBTeX
		EndNote
		RefMan
		Refer
		Medline
		CIF
		SGML
		Text
		Plain Text

Format		BIBTeX
		EndNote
		RefMan
		Refer
		Medline
		CIF
		SGML
		Text
		Plain Text

Search IUCr Journals		doi		Advanced search
Author		volume	page