Bis{μ4-N-[phen­yl(pyridin-2-yl­aza­nid­yl)meth­yl]pyridin-2-aminido}tetra­kis(tetra­hydro­furan)­tetra­lithium

Chen, J.

doi:10.1107/S1600536813031838

metal-organic compounds

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ISSN: 2056-9890

Volume 69| Part 12| December 2013| Page m683

doi:10.1107/S1600536813031838

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Bis{μ₄-N-[phenyl(pyridin-2-ylazanidyl)methyl]pyridin-2-aminido}tetrakis(tetrahydrofuran)tetralithium

Juan Chen ^a ^*

^aDepartment of Chemistry, Taiyuan Teachers College, Taiyuan 030031, People's Republic of China
^*Correspondence e-mail: chenchenj1128@163.com

(Received 29 October 2013; accepted 22 November 2013; online 27 November 2013)

The title complex, [Li₄(C₁₇H₁₄N₄)₂(C₄H₈O)₄], bears a novel tetradentate diamido ligand. In the tetranuclear centrosymmetric complex molecule, the metal atoms exhibit two kinds of coordination modes. The middle two Li⁺ cations are coordinated by four N (ligand) and one O (tetrahydrofuran, THF) atoms, resulting in a distorted square-pyramidal geometry. The outer two Li⁺ cations are in distorted tetrahedral environments consisting of three N (ligand) and one O (THF) atoms. The Li—N bond lengths vary from 2.020 (7) to 2.441 (6)Å.

CCDC reference: 973190

Related literature

For reviews of related metal amides, see: Holm et al. (1996 ); Kempe (2000 ). For reviews of amidinates, see: Edelmann (1994 ); Mohamed (2010 ). For related organometallic compounds with aminopyridinato ligands, see: Kempe (2003 ); Smolensky et al. (2005 ); Talja et al. (2008 ); Polamo & Leskela (1996 ).

Experimental

Crystal data

[Li₄(C₁₇H₁₄N₄)₂(C₄H₈O)₄]
M_r = 864.82
Triclinic, $[P \overline 1]$
a = 10.3322 (10) Å
b = 11.2231 (11) Å
c = 12.4813 (12) Å
α = 111.021 (2)°
β = 105.355 (2)°
γ = 100.763 (2)°
V = 1237.3 (2) Å³
Z = 1
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 295 K
0.20 × 0.15 × 0.15 mm

Data collection

Bruker SMART CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.986, T_max = 0.989
6796 measured reflections
4339 independent reflections
2180 reflections with I > 2σ(I)
R_int = 0.036

Refinement

R[F² > 2σ(F²)] = 0.073
wR(F²) = 0.243
S = 0.93
4339 reflections
298 parameters
61 restraints
H-atom parameters constrained
Δρ_max = 0.37 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Data collection: SMART (Bruker, 2000 ); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXS97.

Supporting information

CCDC reference: 973190

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: 10.1107/S1600536813031838/rk2418sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813031838/rk2418Isup2.hkl

checkCIF report

Comment top

The exploration of ancillary ligand systems supporting catalytically active metal centers is a long-standing demand in the coordination chemistry. The N-donor ligands are important alterneatives instead of the ubiquitous cyclopentadienyl species. Metal amides were found having valuable applications in various industrial and biological processes (Holm et al., 1996; Kempe, 2000). Amidinate ligands have been extensively studied for decades due to their high adaptability to a wide variety of metals and the remarkable utility as homogeneous catalysts for olefin polymerization of corresponding metal complexes (Edelmann, 1994; Mohamed, 2010). As the closest "relatives" amidinates, pyridyl amido ligands like [N(R)(PY)]^- with flexible bonding modes such as the strained N,N'-chelating fashion and the bimetallic bridging binding fashion, have attracted much attention (Kempe, 2003; Smolensky et al., 2005; Talja et al., 2008). Recently, a special N-functionalized aminopyridinato ligand was developed by introducing a linker between two aminopyridinato moieties, possessing the η³:η³ environment. Here, the synthesis and crystal structure of a new lithium complex supported by this ligand will be described.

Aminal bis(2-pyridylamino)toluene is the precursor of the title compound. It was prepared by condensation of two equivalents of 2-aminopyridine and one equivalent of benzaldehyde via reflux in methanol. After lithiation of bis(2-pyridylamino)toluene with two equivalents of butyllithium in diethyl ether, it gave yellow crystals of diamide derivative·However, the crystalline qualitity was not good enough for X-ray crystallography analysis. It is solvated with one molar of Et₂O donor inferred from its ¹H NMR spectrum. The suitable for X-ray investigation single-crystal of the title compound was obtained by recrystallization in THF. Its molecular structure is shown in Fig. 1. It is revealed as a tetranuclear species. The metal centers are bound in a zone composed by two tetradentate diamido ligands and they are seprerated in a zigzag mode with distances of 2.578 (10)Å and 2.633 (8)Å. The Li^···Li distances are obviously longer than that of 2.399 (12)Å in the reported {[NH(Ph)(2-C₅H₄N)]Li[N(Ph)(2-C₅H₄N)]}₂ (Polamo & Leskela, 1996). Each Li is covered by a THF molecule from the outer direction. The molecule is centrosymmetric and its center of inversion coincide with the central point of the middle [LiN]₂ core. There are two different coordination environments employed towards lithium atoms. The middle two lithium atoms are coordinated with four N and one O atoms, resulting in the five-coordinate distorted quadrangular pyramidal geometry. The outer two lithium atoms are in the distorted tetrahedral environment consisting of three N and one O atoms. The distances of Li–N bonds are varying from 2.02 to 2.44Å.

Related literature top

For reviews of related metal amides, see: Holm et al. (1996); Kempe (2000). For reviews of amidinates, see: Edelmann (1994); Mohamed (2010). For related organometallic compounds with aminopyridinato ligands, see: Kempe (2003); Smolensky et al. (2005); Talja et al. (2008); Polamo & Leskela (1996).

Experimental top

A solution of n-BuLi (1.6 M, 2.4 ml, 3.8 mmol) in hexane was slowly added into a solution of di(2-pyridylamino)toluene {PhCH[(2-C₅H₄N)NH]₂} (0.53 g, 1.9 mmol) in Et₂O (30 ml) at 273 K by syringe. The mixture was stirred at room temperature for five hours. Then all the volatiles were removed under vacuum. The residue was recrystallized with THF (20 ml), it gave the title compound as yellow crystals (yield 0.52 g, 62%). M.p.: 413-415 K. ¹H NMR (300 MHz, C₆D₆) δ: 8.3-5.5 (m, 13H;Ph and pyridyl), 3.260 (s, 8H; O–CH₂ of THF), 1.212 (s, 8H; C–CH₂ of THF); ¹³C NMR (75 MHz, C₆D₆) δ: 170-105 (m, Ph and pyridyl), 68.1 (O–CH₂ of THF), 25.8 (C–CH₂ of THF). Anal. Calc. for C₅₀H₆₀Li₄N₈O₄: C, 69.44; H, 6.99; N, 12.96%. Found: C, 69.23; H, 6.96; N, 13.13%.

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXS97 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are omitted for clarity.

Bis{µ₄-N-[phenyl(pyridin-2-ylazanidyl)methyl]pyridin-2-aminido}tetrakis(tetrahydrofuran)tetralithium top

Crystal data top

[Li₄(C₁₇H₁₄N₄)₂(C₄H₈O)₄]	Z = 1
M_r = 864.82	F(000) = 460
Triclinic, P1	D_x = 1.161 Mg m⁻³
Hall symbol: -P 1	Melting point = 413–415 K
a = 10.3322 (10) Å	Mo Kα radiation, λ = 0.71073 Å
b = 11.2231 (11) Å	Cell parameters from 2019 reflections
c = 12.4813 (12) Å	θ = 2.1–23.3°
α = 111.021 (2)°	µ = 0.07 mm⁻¹
β = 105.355 (2)°	T = 295 K
γ = 100.763 (2)°	Prism, yellow
V = 1237.3 (2) Å³	0.20 × 0.15 × 0.15 mm

Data collection top

Bruker SMART CCD diffractometer	4339 independent reflections
Radiation source: fine-focus sealed tube	2180 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.036
ϕ and ω scans	θ_max = 25.0°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −12→9
T_min = 0.986, T_max = 0.989	k = −13→13
6796 measured reflections	l = −14→14

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.073	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.243	H-atom parameters constrained
S = 0.93	w = 1/[σ²(F_o²) + (0.1525P)²] where P = (F_o² + 2F_c²)/3
4339 reflections	(Δ/σ)_max < 0.001
298 parameters	Δρ_max = 0.37 e Å⁻³
61 restraints	Δρ_min = −0.24 e Å⁻³

Crystal data top

[Li₄(C₁₇H₁₄N₄)₂(C₄H₈O)₄]	γ = 100.763 (2)°
M_r = 864.82	V = 1237.3 (2) Å³
Triclinic, P1	Z = 1
a = 10.3322 (10) Å	Mo Kα radiation
b = 11.2231 (11) Å	µ = 0.07 mm⁻¹
c = 12.4813 (12) Å	T = 295 K
α = 111.021 (2)°	0.20 × 0.15 × 0.15 mm
β = 105.355 (2)°

Data collection top

Bruker SMART CCD diffractometer	4339 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2180 reflections with I > 2σ(I)
T_min = 0.986, T_max = 0.989	R_int = 0.036
6796 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.073	61 restraints
wR(F²) = 0.243	H-atom parameters constrained
S = 0.93	Δρ_max = 0.37 e Å⁻³
4339 reflections	Δρ_min = −0.24 e Å⁻³
298 parameters

Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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	0.1027 (6)	0.4551 (5)	1.0323 (5)	0.0634 (14)
Li2	−0.1558 (7)	0.4565 (6)	0.7296 (5)	0.0719 (16)
N1	0.1316 (3)	0.6518 (2)	1.0415 (2)	0.0507 (6)
N2	−0.0351 (2)	0.6392 (2)	0.8668 (2)	0.0535 (7)
N3	0.2796 (3)	0.6487 (3)	1.2128 (2)	0.0667 (8)
N4	−0.2221 (3)	0.6071 (3)	0.7043 (3)	0.0714 (8)
C1	0.1048 (3)	0.7175 (3)	0.9599 (3)	0.0512 (8)
H1A	0.1048	0.8086	1.0070	0.061*
C2	0.2139 (3)	0.7251 (3)	0.8981 (3)	0.0579 (8)
C3	0.2904 (4)	0.8443 (4)	0.9055 (4)	0.0795 (11)
H3	0.2775	0.9239	0.9518	0.095*
C4	0.3849 (5)	0.8494 (6)	0.8466 (5)	0.1126 (17)
H4	0.4342	0.9311	0.8523	0.135*
C5	0.4057 (6)	0.7349 (8)	0.7805 (6)	0.131 (2)
H5	0.4705	0.7379	0.7415	0.157*
C6	0.3321 (6)	0.6141 (6)	0.7703 (5)	0.1191 (17)
H6	0.3464	0.5356	0.7234	0.143*
C7	0.2354 (4)	0.6077 (4)	0.8299 (4)	0.0845 (11)
H7	0.1863	0.5256	0.8238	0.101*
C8	0.2470 (3)	0.7188 (3)	1.1439 (3)	0.0514 (8)
C9	0.3386 (3)	0.8526 (3)	1.1891 (3)	0.0622 (9)
H9	0.3176	0.9039	1.1466	0.075*
C10	0.4549 (4)	0.9057 (4)	1.2924 (3)	0.0849 (12)
H10	0.5125	0.9932	1.3207	0.102*
C11	0.4887 (5)	0.8315 (5)	1.3556 (4)	0.1027 (15)
H11	0.5699	0.8661	1.4256	0.123*
C12	0.3998 (4)	0.7060 (4)	1.3127 (4)	0.0876 (12)
H12	0.4233	0.6554	1.3554	0.105*
C13	−0.1040 (3)	0.6970 (3)	0.8038 (3)	0.0526 (8)
C14	−0.0715 (4)	0.8342 (3)	0.8263 (3)	0.0633 (9)
H14	0.0104	0.8966	0.8904	0.076*
C15	−0.1585 (4)	0.8755 (4)	0.7552 (4)	0.0778 (11)
H15	−0.1373	0.9661	0.7722	0.093*
C16	−0.2783 (4)	0.7838 (5)	0.6580 (4)	0.0926 (13)
H16	−0.3396	0.8106	0.6089	0.111*
C17	−0.3032 (4)	0.6530 (4)	0.6367 (4)	0.0869 (13)
H17	−0.3829	0.5906	0.5700	0.104*
C18	0.1501 (7)	0.2098 (6)	0.8819 (7)	0.183 (3)
H18A	0.1227	0.1720	0.9344	0.220*
H18B	0.0681	0.1811	0.8082	0.220*
C19	0.2581 (9)	0.1655 (7)	0.8507 (9)	0.195 (3)
H19A	0.2663	0.0902	0.8699	0.234*
H19B	0.2384	0.1368	0.7633	0.234*
C20	0.3791 (8)	0.2697 (8)	0.9169 (9)	0.223 (4)
H20A	0.4211	0.2913	0.8626	0.268*
H20B	0.4465	0.2473	0.9710	0.268*
C21	0.3420 (6)	0.3833 (7)	0.9886 (7)	0.180 (3)
H21A	0.3758	0.4013	1.0749	0.216*
H21B	0.3845	0.4630	0.9810	0.216*
O1	0.1996 (3)	0.3504 (3)	0.9441 (3)	0.0881 (9)
C22	−0.1386 (12)	0.1945 (8)	0.5649 (9)	0.231 (4)
H22A	−0.2398	0.1501	0.5322	0.277*
H22B	−0.0961	0.1731	0.6320	0.277*
C23	−0.0822 (14)	0.1475 (9)	0.4711 (11)	0.264 (4)
H23A	−0.0064	0.1126	0.4966	0.317*
H23B	−0.1547	0.0782	0.3953	0.317*
C24	−0.0334 (14)	0.2597 (12)	0.4575 (11)	0.279 (4)
H24A	−0.0746	0.2419	0.3717	0.334*
H24B	0.0683	0.2821	0.4797	0.334*
C25	−0.0648 (11)	0.3669 (9)	0.5286 (8)	0.230 (4)
H25A	0.0187	0.4455	0.5738	0.276*
H25B	−0.1372	0.3878	0.4776	0.276*
O2	−0.1117 (4)	0.3306 (3)	0.6075 (3)	0.1187 (12)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Li1	0.064 (3)	0.059 (3)	0.079 (4)	0.023 (3)	0.031 (3)	0.037 (3)
Li2	0.080 (4)	0.064 (3)	0.063 (3)	0.009 (3)	0.018 (3)	0.029 (3)
N1	0.0509 (15)	0.0478 (13)	0.0523 (14)	0.0125 (12)	0.0178 (13)	0.0225 (12)
N2	0.0461 (15)	0.0511 (14)	0.0602 (15)	0.0103 (12)	0.0138 (12)	0.0272 (13)
N3	0.0630 (18)	0.0670 (17)	0.0655 (17)	0.0099 (14)	0.0115 (14)	0.0373 (15)
N4	0.0597 (18)	0.0733 (18)	0.0683 (17)	0.0037 (15)	0.0059 (15)	0.0374 (16)
C1	0.0485 (18)	0.0443 (15)	0.0595 (18)	0.0120 (13)	0.0186 (15)	0.0229 (15)
C2	0.0495 (19)	0.066 (2)	0.064 (2)	0.0160 (16)	0.0212 (16)	0.0355 (17)
C3	0.065 (2)	0.097 (3)	0.093 (3)	0.017 (2)	0.033 (2)	0.059 (2)
C4	0.085 (3)	0.151 (5)	0.135 (4)	0.024 (3)	0.056 (3)	0.093 (4)
C5	0.095 (4)	0.213 (7)	0.141 (5)	0.050 (5)	0.075 (4)	0.113 (5)
C6	0.118 (4)	0.149 (5)	0.122 (4)	0.063 (4)	0.080 (3)	0.055 (4)
C7	0.081 (3)	0.095 (3)	0.095 (3)	0.034 (2)	0.049 (2)	0.045 (2)
C8	0.0480 (18)	0.0505 (17)	0.0550 (18)	0.0119 (14)	0.0188 (15)	0.0236 (15)
C9	0.065 (2)	0.0515 (18)	0.061 (2)	0.0074 (16)	0.0144 (17)	0.0261 (16)
C10	0.078 (3)	0.072 (2)	0.074 (2)	−0.012 (2)	0.004 (2)	0.033 (2)
C11	0.082 (3)	0.108 (3)	0.082 (3)	−0.009 (3)	−0.012 (2)	0.050 (3)
C12	0.074 (3)	0.097 (3)	0.080 (3)	0.002 (2)	0.000 (2)	0.057 (2)
C13	0.0500 (18)	0.0551 (18)	0.0578 (18)	0.0145 (15)	0.0228 (15)	0.0284 (16)
C14	0.063 (2)	0.061 (2)	0.070 (2)	0.0207 (16)	0.0217 (17)	0.0331 (18)
C15	0.077 (3)	0.078 (2)	0.098 (3)	0.036 (2)	0.033 (2)	0.054 (2)
C16	0.073 (3)	0.117 (3)	0.108 (3)	0.034 (3)	0.022 (3)	0.076 (3)
C17	0.063 (3)	0.103 (3)	0.085 (3)	0.006 (2)	0.001 (2)	0.058 (2)
C18	0.167 (6)	0.094 (4)	0.239 (7)	0.018 (4)	0.127 (5)	−0.009 (4)
C19	0.182 (6)	0.104 (4)	0.262 (7)	0.062 (4)	0.092 (5)	0.020 (4)
C20	0.128 (5)	0.192 (6)	0.248 (7)	0.087 (4)	0.042 (5)	−0.015 (5)
C21	0.082 (4)	0.155 (5)	0.223 (6)	0.051 (3)	0.049 (4)	−0.006 (5)
O1	0.0756 (18)	0.0718 (17)	0.133 (2)	0.0333 (14)	0.0538 (16)	0.0442 (17)
C22	0.356 (10)	0.121 (5)	0.238 (8)	0.089 (6)	0.167 (7)	0.052 (5)
C23	0.372 (9)	0.162 (7)	0.239 (7)	0.105 (7)	0.172 (7)	0.012 (6)
C24	0.365 (9)	0.240 (9)	0.225 (7)	0.080 (8)	0.197 (6)	0.037 (7)
C25	0.350 (9)	0.202 (8)	0.191 (6)	0.073 (7)	0.195 (6)	0.078 (6)
O2	0.172 (3)	0.085 (2)	0.091 (2)	0.021 (2)	0.070 (2)	0.0226 (17)

Geometric parameters (Å, º) top

Li1—O1	1.921 (6)	C9—C10	1.350 (5)
Li1—N2ⁱ	2.084 (6)	C9—H9	0.9300
Li1—N1	2.128 (6)	C10—C11	1.368 (5)
Li1—N1ⁱ	2.256 (6)	C10—H10	0.9300
Li1—N3	2.441 (6)	C11—C12	1.352 (5)
Li1—Li1ⁱ	2.578 (10)	C11—H11	0.9300
Li1—Li2ⁱ	2.633 (8)	C12—Li2ⁱ	2.617 (7)
Li1—C1ⁱ	2.656 (6)	C12—H12	0.9300
Li1—C8	2.686 (6)	C13—C14	1.418 (4)
Li2—O2	1.895 (7)	C14—C15	1.356 (5)
Li2—N3ⁱ	2.020 (7)	C14—H14	0.9300
Li2—N2	2.022 (6)	C15—C16	1.377 (5)
Li2—N4	2.032 (7)	C15—H15	0.9300
Li2—C13	2.415 (6)	C16—C17	1.354 (5)
Li2—C12ⁱ	2.617 (7)	C16—H16	0.9300
Li2—Li1ⁱ	2.633 (8)	C17—H17	0.9300
N1—C8	1.337 (4)	C18—C19	1.393 (9)
N1—C1	1.458 (4)	C18—O1	1.402 (6)
N1—Li1ⁱ	2.256 (6)	C18—H18A	0.9700
N2—C13	1.336 (4)	C18—H18B	0.9700
N2—C1	1.455 (4)	C19—C20	1.352 (9)
N2—Li1ⁱ	2.084 (6)	C19—H19A	0.9700
N3—C12	1.349 (4)	C19—H19B	0.9700
N3—C8	1.379 (4)	C20—C21	1.455 (8)
N3—Li2ⁱ	2.020 (7)	C20—H20A	0.9700
N4—C17	1.333 (4)	C20—H20B	0.9700
N4—C13	1.374 (4)	C21—O1	1.351 (5)
C1—C2	1.531 (4)	C21—H21A	0.9700
C1—Li1ⁱ	2.656 (6)	C21—H21B	0.9700
C1—H1A	0.9800	C22—O2	1.369 (8)
C2—C3	1.378 (5)	C22—C23	1.422 (12)
C2—C7	1.384 (5)	C22—H22A	0.9700
C3—C4	1.374 (6)	C22—H22B	0.9700
C3—H3	0.9300	C23—C24	1.352 (11)
C4—C5	1.347 (8)	C23—H23A	0.9700
C4—H4	0.9300	C23—H23B	0.9700
C5—C6	1.369 (8)	C24—C25	1.368 (11)
C5—H5	0.9300	C24—H24A	0.9700
C6—C7	1.400 (6)	C24—H24B	0.9700
C6—H6	0.9300	C25—O2	1.355 (7)
C7—H7	0.9300	C25—H25A	0.9700
C8—C9	1.430 (4)	C25—H25B	0.9700

O1—Li1—N2ⁱ	107.8 (3)	C5—C6—C7	120.5 (5)
O1—Li1—N1	116.0 (3)	C5—C6—H6	119.7
N2ⁱ—Li1—N1	134.1 (3)	C7—C6—H6	119.7
O1—Li1—N1ⁱ	112.1 (3)	C2—C7—C6	119.1 (4)
N2ⁱ—Li1—N1ⁱ	64.89 (18)	C2—C7—H7	120.5
N1—Li1—N1ⁱ	108.0 (2)	C6—C7—H7	120.5
O1—Li1—N3	108.2 (3)	N1—C8—N3	115.0 (3)
N2ⁱ—Li1—N3	94.7 (2)	N1—C8—C9	127.9 (3)
N1—Li1—N3	59.72 (16)	N3—C8—C9	117.2 (3)
N1ⁱ—Li1—N3	138.7 (3)	N1—C8—Li1	51.44 (18)
O1—Li1—Li1ⁱ	133.7 (4)	N3—C8—Li1	64.8 (2)
N2ⁱ—Li1—Li1ⁱ	101.7 (3)	C9—C8—Li1	169.4 (3)
N1—Li1—Li1ⁱ	56.3 (2)	C10—C9—C8	121.2 (3)
N1ⁱ—Li1—Li1ⁱ	51.7 (2)	C10—C9—H9	119.4
N3—Li1—Li1ⁱ	104.0 (3)	C8—C9—H9	119.4
O1—Li1—Li2ⁱ	125.5 (3)	C9—C10—C11	120.4 (3)
N2ⁱ—Li1—Li2ⁱ	49.08 (19)	C9—C10—H10	119.8
N1—Li1—Li2ⁱ	92.4 (2)	C11—C10—H10	119.8
N1ⁱ—Li1—Li2ⁱ	100.1 (3)	C12—C11—C10	117.6 (4)
N3—Li1—Li2ⁱ	46.73 (17)	C12—C11—H11	121.2
Li1ⁱ—Li1—Li2ⁱ	100.8 (3)	C10—C11—H11	121.2
O1—Li1—C1ⁱ	106.6 (2)	N3—C12—C11	124.9 (4)
N2ⁱ—Li1—C1ⁱ	33.02 (12)	N3—C12—Li2ⁱ	49.5 (2)
N1—Li1—C1ⁱ	133.0 (3)	C11—C12—Li2ⁱ	150.8 (4)
N1ⁱ—Li1—C1ⁱ	33.27 (11)	N3—C12—H12	117.5
N3—Li1—C1ⁱ	124.3 (2)	C11—C12—H12	117.5
Li1ⁱ—Li1—C1ⁱ	80.3 (3)	Li2ⁱ—C12—H12	76.1
Li2ⁱ—Li1—C1ⁱ	77.7 (2)	N2—C13—N4	113.1 (3)
O1—Li1—C8	111.9 (3)	N2—C13—C14	129.1 (3)
N2ⁱ—Li1—C8	119.9 (3)	N4—C13—C14	117.8 (3)
N1—Li1—C8	29.44 (11)	N2—C13—Li2	56.8 (2)
N1ⁱ—Li1—C8	130.5 (2)	N4—C13—Li2	57.2 (2)
N3—Li1—C8	30.74 (11)	C14—C13—Li2	169.5 (3)
Li1ⁱ—Li1—C8	81.4 (2)	C15—C14—C13	120.7 (3)
Li2ⁱ—Li1—C8	71.15 (19)	C15—C14—H14	119.7
C1ⁱ—Li1—C8	139.8 (2)	C13—C14—H14	119.7
O2—Li2—N3ⁱ	107.2 (3)	C14—C15—C16	120.3 (4)
O2—Li2—N2	130.7 (4)	C14—C15—H15	119.9
N3ⁱ—Li2—N2	111.3 (3)	C16—C15—H15	119.9
O2—Li2—N4	121.6 (3)	C17—C16—C15	117.3 (3)
N3ⁱ—Li2—N4	113.6 (3)	C17—C16—H16	121.3
N2—Li2—N4	67.9 (2)	C15—C16—H16	121.3
O2—Li2—C13	131.3 (3)	N4—C17—C16	124.9 (4)
N3ⁱ—Li2—C13	121.3 (3)	N4—C17—H17	117.5
N2—Li2—C13	33.59 (13)	C16—C17—H17	117.5
N4—Li2—C13	34.67 (14)	C19—C18—O1	108.4 (5)
O2—Li2—C12ⁱ	95.7 (3)	C19—C18—H18A	110.0
N3ⁱ—Li2—C12ⁱ	30.49 (14)	O1—C18—H18A	110.0
N2—Li2—C12ⁱ	132.5 (3)	C19—C18—H18B	110.0
N4—Li2—C12ⁱ	98.8 (3)	O1—C18—H18B	110.0
C13—Li2—C12ⁱ	123.6 (3)	H18A—C18—H18B	108.4
O2—Li2—Li1ⁱ	138.0 (3)	C20—C19—C18	107.3 (6)
N3ⁱ—Li2—Li1ⁱ	61.6 (2)	C20—C19—H19A	110.3
N2—Li2—Li1ⁱ	51.15 (18)	C18—C19—H19A	110.3
N4—Li2—Li1ⁱ	98.5 (3)	C20—C19—H19B	110.3
C13—Li2—Li1ⁱ	75.6 (2)	C18—C19—H19B	110.3
C12ⁱ—Li2—Li1ⁱ	89.3 (2)	H19A—C19—H19B	108.5
C8—N1—C1	115.8 (2)	C19—C20—C21	106.9 (6)
C8—N1—Li1	99.1 (2)	C19—C20—H20A	110.3
C1—N1—Li1	139.7 (2)	C21—C20—H20A	110.3
C8—N1—Li1ⁱ	144.3 (2)	C19—C20—H20B	110.3
C1—N1—Li1ⁱ	88.6 (2)	C21—C20—H20B	110.3
Li1—N1—Li1ⁱ	72.0 (2)	H20A—C20—H20B	108.6
C13—N2—C1	118.7 (2)	O1—C21—C20	107.3 (5)
C13—N2—Li2	89.6 (2)	O1—C21—H21A	110.3
C1—N2—Li2	144.8 (3)	C20—C21—H21A	110.3
C13—N2—Li1ⁱ	128.5 (2)	O1—C21—H21B	110.3
C1—N2—Li1ⁱ	95.7 (2)	C20—C21—H21B	110.3
Li2—N2—Li1ⁱ	79.8 (2)	H21A—C21—H21B	108.5
C12—N3—C8	118.5 (3)	C21—O1—C18	105.4 (4)
C12—N3—Li2ⁱ	100.0 (3)	C21—O1—Li1	121.2 (4)
C8—N3—Li2ⁱ	130.2 (3)	C18—O1—Li1	123.5 (3)
C12—N3—Li1	152.4 (3)	O2—C22—C23	109.8 (8)
C8—N3—Li1	84.5 (2)	O2—C22—H22A	109.7
Li2ⁱ—N3—Li1	71.6 (2)	C23—C22—H22A	109.7
C17—N4—C13	118.9 (3)	O2—C22—H22B	109.7
C17—N4—Li2	151.9 (3)	C23—C22—H22B	109.7
C13—N4—Li2	88.1 (2)	H22A—C22—H22B	108.2
N2—C1—N1	106.5 (2)	C24—C23—C22	102.6 (9)
N2—C1—C2	109.9 (2)	C24—C23—H23A	111.2
N1—C1—C2	112.9 (2)	C22—C23—H23A	111.2
N2—C1—Li1ⁱ	51.31 (18)	C24—C23—H23B	111.2
N1—C1—Li1ⁱ	58.11 (18)	C22—C23—H23B	111.2
C2—C1—Li1ⁱ	142.4 (2)	H23A—C23—H23B	109.2
N2—C1—H1A	109.2	C23—C24—C25	112.4 (10)
N1—C1—H1A	109.2	C23—C24—H24A	109.1
C2—C1—H1A	109.2	C25—C24—H24A	109.1
Li1ⁱ—C1—H1A	108.0	C23—C24—H24B	109.1
C3—C2—C7	118.2 (3)	C25—C24—H24B	109.1
C3—C2—C1	122.7 (3)	H24A—C24—H24B	107.9
C7—C2—C1	119.1 (3)	O2—C25—C24	106.5 (8)
C4—C3—C2	122.2 (4)	O2—C25—H25A	110.4
C4—C3—H3	118.9	C24—C25—H25A	110.4
C2—C3—H3	118.9	O2—C25—H25B	110.4
C5—C4—C3	119.3 (5)	C24—C25—H25B	110.4
C5—C4—H4	120.3	H25A—C25—H25B	108.6
C3—C4—H4	120.3	C25—O2—C22	106.9 (6)
C4—C5—C6	120.6 (5)	C25—O2—Li2	119.8 (5)
C4—C5—H5	119.7	C22—O2—Li2	132.3 (5)
C6—C5—H5	119.7

Symmetry code: (i) −x, −y+1, −z+2.

Experimental details

Crystal data
Chemical formula	[Li₄(C₁₇H₁₄N₄)₂(C₄H₈O)₄]
M_r	864.82
Crystal system, space group	Triclinic, P1
Temperature (K)	295
a, b, c (Å)	10.3322 (10), 11.2231 (11), 12.4813 (12)
α, β, γ (°)	111.021 (2), 105.355 (2), 100.763 (2)
V (Å³)	1237.3 (2)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	0.07
Crystal size (mm)	0.20 × 0.15 × 0.15

Data collection
Diffractometer	Bruker SMART CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.986, 0.989
No. of measured, independent and observed [I > 2σ(I)] reflections	6796, 4339, 2180
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.073, 0.243, 0.93
No. of reflections	4339
No. of parameters	298
No. of restraints	61
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.37, −0.24

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

This work was supported by grants from the Natural Science Foundation of China (20702029) and the Natural Science Foundation of Shanxi Province (2008011024).

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