The azide-bridged mixed-valent cobalt(II,III) compound [(CH3)3NH]2[CoIICo2III(N3)10]

Liu, Y.-J.; Li, Y.-X.; Xu, M.; Wang, X.

doi:10.1107/S1600536810049421

metal-organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 67| Part 1| January 2011| Page m27

https://doi.org/10.1107/S1600536810049421

Open

access

The azide-bridged mixed-valent cobalt(II,III) compound [(CH₃)₃NH]₂[Co^IICo₂^III(N₃)₁₀]

Yan-Ju Liu,^a ^* Yu-Xian Li,^a Min Xu ^a and Xia Wang ^a

^aPharmacy College, Henan University of Traditional Chinese Medicine, Zhengzhou 450008, People's Republic of China
^*Correspondence e-mail: liuyanju886@163.com

(Received 14 November 2010; accepted 26 November 2010; online 4 December 2010)

The crystal structure of the title compound, poly[bis(trimethylammonium) hexa-μ_1,1-azido-tetraazidotricobaltate(II,III)], [(CH₃)₃NH]₂[Co^IICo^III₂(N₃)₁₀], consists of anionic chains [Co^IICo^III₂(N₃)₁₀]²⁻ extending parallel to the c axis and [(CH₃)₃NH]⁺ counter-cations situated between the chains. In the anionic chain, one tetrahedrally coordinated Co^II atom (site symmetry 2) and two octahedrally coordinated Co^III atoms are arranged alternately and are linked by μ_1,1-azide bridges. The anionic chains and cations are connected via N—H⋯N hydrogen bonding into a three-dimensional structure.

Related literature

For background to transition-metal azido-complexes templated by counter-cations of various sizes, see: Liu et al. (2006 , 2008 ). For related cobalt complexes, see: Zhang et al. (2010 ).

Experimental

Crystal data

(C₃H₁₀N)₂[Co₃(N₃)₁₀]
M_r = 717.33
Monoclinic, C 2/c
a = 21.7200 (6) Å
b = 11.3812 (4) Å
c = 12.1628 (4) Å
β = 115.524 (2)°
V = 2713.21 (15) Å³
Z = 4
Mo Kα radiation
μ = 1.88 mm⁻¹
T = 293 K
0.10 × 0.06 × 0.05 mm

Data collection

Rigaku Saturn diffractometer
Absorption correction: multi-scan (REQAB; Jacobson, 1998 ) T_min = 0.708, T_max = 0.823
22049 measured reflections
2389 independent reflections
1481 reflections with I > 2σ(I)
R_int = 0.103

Refinement

R[F² > 2σ(F²)] = 0.032
wR(F²) = 0.061
S = 0.98
2389 reflections
190 parameters
24 restraints
H-atom parameters constrained
Δρ_max = 0.31 e Å⁻³
Δρ_min = −0.35 e Å⁻³

Table 1
Selected bond lengths (Å)

Co1—N7	1.944 (3)
Co1—N4	1.948 (3)
Co1—N10	1.964 (3)
Co1—N1	1.979 (3)
Co1—N13ⁱ	2.008 (3)
Co1—N13	2.008 (3)
Co2—N1ⁱⁱ	1.968 (3)
Co2—N1	1.968 (3)
Co2—N10ⁱ	2.014 (3)
Co2—N10ⁱⁱⁱ	2.014 (3)
Symmetry codes: (i) -x, -y, -z; (ii) $[-x, y, -z+{\script{1\over 2}}]$ ; (iii) $[x, -y, z+{\script{1\over 2}}]$ .

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N16—H16⋯N7	0.91	2.02	2.890	159

Data collection: CrystalClear (Rigaku/MSC, 2006 ); cell refinement: CrystalClear; data reduction: CrystalClear; 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: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810049421/wm2430sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810049421/wm2430Isup2.hkl

checkCIF report

Comment top

Azido-bridged complexes have attracted a lot of attention in recent times because of their importance in diverse fields, encompassing condensed matter physics, materials chemistry, biological chemistry, etc. Having diverse coordination modes and being an efficient magnetic coupler, the azide anion is a versatile ligand in bridging different transition metals, generating rich and fascinating architectures ranging from discrete polynuclears to extended three-dimensional networks with interesting magnetic properties (antiferromagnetic, ferromagnetic, ferrimagnetic, canted and alternating systems). In fact, remarkable structural variations of azido-bridged complexes have been reported by using various ancillary ligands, with different number of coordination sites and steric hindrance, to control over the dimensions of complexes and bridging modes of the azide anions, thus leading to the control over their magnetic properties. However, only a few metal-azido systems devoid of ancillary ligands have been obtained by varying the size of the coutercations (Liu et al., 2006, 2008). A small coutercation such as (CH₃)₄N⁺ produced the one-dimensional ferromagnetic complex [(CH₃)₄N][Cu(N₃)₃], in which the Cu(II) ions are connected by a triple azido-bridge, including two µ_1,3-N₃ and one µ_1,1-N₃ anions. When more bulky coutercations were employed, the mononuclear paramagnetic complex [(CH₃CH₂)₄N]₂[Cu(N₃)₄], the dinuclear antiferromagnetic complex [(CH₃CH₂CH₂CH₂)₄N]₂[Cu₂(N₃)₆] and the one-dimensional ferromagnetic complex [(CH₃CH₂CH₂)₄N]₂[Cu₃(N₃)₈] were obtained separately. For magnese(II)-azido complexes, use of small coutercations like (CH₃)₄N⁺ and Cs⁺ produced compounds with interesting three-dimensional structures [(CH₃)₄N][Mn(N₃)₃] and Cs[Mn(N₃)₃], where the cations are situated in the voids the anionic Mn^II-azido network. When using the more bulky cation (CH₃CH₂)₄N⁺, the one-dimensional ferromagnetic complex [(CH₃CH₂)₄N][Mn(N₃)₃] was obtained. Despite the results obtained above, azido-bridged complexes with mixed-valent metal ions have not been reported. In this work, we report on a mixed-valence cobalt(II,III) complex, [(CH₃)₃NH]₂[Co^IICo^III₂(N₃)₁₀], (I).

The structure of (I) consists of anionic chains [Co^IICo^III₂(N₃)₁₀]^2- extending parallel to the c-axis. The [(CH₃)₃NH]⁺ countercations are situated between the chains (Fig. 1). In the [Co^IICo^III₂(N₃)₁₀]^2- anionic chain, the Co^II atom (Co2, site symmetry 2) is tetrahedrally coordinated by N atoms, whereas the Co^III atom (Co1) is octahedrally coordinated. Co^II and Co^III atoms are linked by µ_1,1-azido ligands and are alternatively arranged along the chain direction. The Co1—N distances range between 1.944 (3)–2.008 (3) Å, slightly longer than those expected for Co^III. The Co2—N distances range between 1.968 (3)–2.014 (3) Å, slightly shorter than those expected for Co^II (Zhang et al., 2010). The anionic chain and the cations are connected via N—H···N hydrogen bonding between the donating N—H function of the cation and non-bridging azido groups of the anion (Fig 2).

Related literature top

For background to transition-metal azido-complexes templated by counter-cations with various sizes, see: Liu et al. (2006, 2008). For related cobalt complexes, see: Zhang et al. (2010).

Experimental top

In a test tube a 5 ml methanol solution of 0.10M Co(ClO₄)₂^.6H₂O was layered carefully with 3 ml methanol and then with 10 ml methanol solution of 0.20M HCl, 0.20M NaN₃, and 0.10M trimethylamine. The tube was sealed and kept undisturbed. Tiny red columnar crystals appeared overnight. Crystallization time of one week produced crystals in a yield of 25% based on the metal salt.

Structure description top

For background to transition-metal azido-complexes templated by counter-cations with various sizes, see: Liu et al. (2006, 2008). For related cobalt complexes, see: Zhang et al. (2010).

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2006); cell refinement: CrystalClear (Rigaku/MSC, 2006); data reduction: CrystalClear (Rigaku/MSC, 2006); 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: publCIF (Westrip, 2010).

Figures top

	Fig. 1. The asymmetric unit of the title structure. All non-H atoms are labelled and are shown with displacement ellipsoids at the 30% probability level. H atoms have been omitted.
	Fig. 2. A view of the crystal packing along the c axis.

poly[bis(trimethylammonium) [hexa-µ_1,1-azido-tetraazidotricobaltate(II,III)]] top

Crystal data top

(C₃H₁₀N)₂[Co₃(N₃)₁₀]	F(000) = 1444
M_r = 717.33	D_x = 1.756 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 14377 reflections
a = 21.7200 (6) Å	θ = 3.4–25.0°
b = 11.3812 (4) Å	µ = 1.88 mm⁻¹
c = 12.1628 (4) Å	T = 293 K
β = 115.524 (2)°	Pillar, red
V = 2713.21 (15) Å³	0.10 × 0.06 × 0.05 mm
Z = 4

Data collection top

Rigaku Saturn diffractometer	2389 independent reflections
Radiation source: fine-focus sealed tube	1481 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.103
Detector resolution: 0.76 pixels mm^-1	θ_max = 25.0°, θ_min = 3.6°
dtprofit.ref scans	h = −25→25
Absorption correction: multi-scan (REQAB; Jacobson, 1998)	k = −13→13
T_min = 0.708, T_max = 0.823	l = −14→14
22049 measured reflections

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)] = 0.032	H-atom parameters constrained
wR(F²) = 0.061	w = 1/[σ²(F_o²) + (0.0204P)²] where P = (F_o² + 2F_c²)/3
S = 0.98	(Δ/σ)_max = 0.001
2389 reflections	Δρ_max = 0.31 e Å⁻³
190 parameters	Δρ_min = −0.35 e Å⁻³
24 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.00084 (18)

Crystal data top

(C₃H₁₀N)₂[Co₃(N₃)₁₀]	V = 2713.21 (15) Å³
M_r = 717.33	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 21.7200 (6) Å	µ = 1.88 mm⁻¹
b = 11.3812 (4) Å	T = 293 K
c = 12.1628 (4) Å	0.10 × 0.06 × 0.05 mm
β = 115.524 (2)°

Data collection top

Rigaku Saturn diffractometer	2389 independent reflections
Absorption correction: multi-scan (REQAB; Jacobson, 1998)	1481 reflections with I > 2σ(I)
T_min = 0.708, T_max = 0.823	R_int = 0.103
22049 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.032	24 restraints
wR(F²) = 0.061	H-atom parameters constrained
S = 0.98	Δρ_max = 0.31 e Å⁻³
2389 reflections	Δρ_min = −0.35 e Å⁻³
190 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

	x	y	z	U_iso*/U_eq
Co1	0.04965 (2)	0.10300 (4)	0.05706 (4)	0.03529 (17)
Co2	0.0000	−0.04737 (5)	0.2500	0.0402 (2)
N1	0.06948 (14)	0.0409 (2)	0.2209 (3)	0.0428 (6)
N2	0.12002 (17)	0.0827 (3)	0.3042 (3)	0.0448 (6)
N3	0.16669 (18)	0.1210 (3)	0.3810 (3)	0.0740 (10)
N4	0.14720 (14)	0.1256 (2)	0.1097 (3)	0.0523 (7)
N5	0.16894 (15)	0.1348 (3)	0.0363 (3)	0.0540 (7)
N6	0.1925 (2)	0.1442 (4)	−0.0308 (4)	0.1069 (15)
N7	0.04578 (16)	0.2621 (2)	0.1120 (3)	0.0489 (8)
N8	−0.00656 (18)	0.3009 (3)	0.1097 (3)	0.0504 (8)
N9	−0.05415 (18)	0.3426 (3)	0.1100 (3)	0.0806 (12)
N10	0.02748 (13)	0.1593 (3)	−0.1084 (2)	0.0434 (6)
N11	0.04393 (15)	0.2609 (3)	−0.1156 (2)	0.0492 (6)
N12	0.0599 (2)	0.3555 (3)	−0.1195 (3)	0.0930 (13)
N13	−0.04827 (13)	0.0595 (2)	0.0083 (2)	0.0384 (6)
N14	−0.09288 (16)	0.1253 (3)	−0.0627 (3)	0.0425 (6)
N15	−0.13450 (17)	0.1858 (3)	−0.1255 (3)	0.0715 (10)
N16	0.16193 (14)	0.4179 (3)	0.2144 (3)	0.0539 (8)
H16	0.1336	0.3554	0.1828	0.065*
C1	0.2022 (2)	0.3949 (5)	0.3459 (4)	0.1044 (17)
H1A	0.2292	0.4628	0.3840	0.157*
H1B	0.2316	0.3287	0.3565	0.157*
H1C	0.1719	0.3783	0.3826	0.157*
C2	0.1190 (3)	0.5217 (4)	0.1950 (5)	0.1125 (19)
H2A	0.0852	0.5067	0.2242	0.169*
H2B	0.0970	0.5396	0.1096	0.169*
H2C	0.1468	0.5871	0.2384	0.169*
C3	0.2062 (2)	0.4251 (5)	0.1509 (4)	0.1121 (19)
H3A	0.1787	0.4379	0.0655	0.168*
H3B	0.2311	0.3529	0.1621	0.168*
H3C	0.2377	0.4891	0.1837	0.168*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Co1	0.0382 (3)	0.0364 (3)	0.0331 (3)	−0.0041 (2)	0.0171 (2)	−0.0013 (2)
Co2	0.0487 (4)	0.0370 (4)	0.0412 (5)	0.000	0.0253 (4)	0.000
N1	0.0456 (15)	0.0502 (15)	0.0338 (16)	−0.0052 (12)	0.0181 (13)	0.0022 (12)
N2	0.0475 (15)	0.0518 (15)	0.0353 (16)	−0.0042 (13)	0.0180 (13)	0.0033 (13)
N3	0.065 (2)	0.095 (3)	0.052 (2)	−0.019 (2)	0.015 (2)	−0.006 (2)
N4	0.0449 (15)	0.0647 (16)	0.0528 (17)	−0.0104 (12)	0.0264 (12)	−0.0027 (13)
N5	0.0453 (15)	0.0637 (16)	0.0561 (18)	−0.0079 (12)	0.0249 (13)	−0.0055 (13)
N6	0.097 (3)	0.148 (4)	0.112 (4)	−0.027 (3)	0.079 (3)	−0.026 (3)
N7	0.061 (2)	0.0407 (19)	0.051 (2)	−0.0085 (16)	0.0293 (18)	−0.0088 (15)
N8	0.062 (2)	0.040 (2)	0.050 (2)	−0.0019 (17)	0.025 (2)	−0.0050 (15)
N9	0.071 (3)	0.068 (3)	0.103 (3)	0.009 (2)	0.037 (3)	−0.020 (2)
N10	0.0570 (15)	0.0435 (16)	0.0329 (14)	−0.0095 (13)	0.0222 (12)	0.0004 (13)
N11	0.0626 (15)	0.0478 (16)	0.0348 (15)	−0.0086 (14)	0.0186 (12)	0.0007 (13)
N12	0.150 (4)	0.054 (2)	0.064 (3)	−0.036 (2)	0.036 (3)	0.004 (2)
N13	0.0378 (15)	0.0388 (15)	0.0414 (17)	−0.0002 (10)	0.0197 (13)	−0.0025 (11)
N14	0.0408 (15)	0.0412 (16)	0.0447 (17)	−0.0017 (11)	0.0176 (13)	−0.0036 (11)
N15	0.058 (2)	0.058 (2)	0.081 (3)	0.0085 (19)	0.014 (2)	0.005 (2)
N16	0.0501 (19)	0.050 (2)	0.061 (2)	−0.0163 (15)	0.0234 (19)	−0.0118 (16)
C1	0.083 (3)	0.143 (5)	0.067 (4)	−0.039 (3)	0.013 (3)	0.007 (3)
C2	0.115 (4)	0.052 (3)	0.165 (6)	0.015 (3)	0.055 (4)	−0.001 (3)
C3	0.093 (4)	0.173 (5)	0.099 (4)	−0.055 (4)	0.069 (3)	−0.045 (4)

Geometric parameters (Å, º) top

Co1—N7	1.944 (3)	N11—N12	1.139 (4)
Co1—N4	1.948 (3)	N13—N14	1.234 (4)
Co1—N10	1.964 (3)	N13—Co1ⁱ	2.008 (3)
Co1—N1	1.979 (3)	N14—N15	1.131 (4)
Co1—N13ⁱ	2.008 (3)	N16—C2	1.460 (5)
Co1—N13	2.008 (3)	N16—C3	1.473 (4)
Co2—N1ⁱⁱ	1.968 (3)	N16—C1	1.478 (5)
Co2—N1	1.968 (3)	N16—H16	0.9100
Co2—N10ⁱ	2.014 (3)	C1—H1A	0.9600
Co2—N10ⁱⁱⁱ	2.014 (3)	C1—H1B	0.9600
N1—N2	1.224 (4)	C1—H1C	0.9600
N2—N3	1.129 (4)	C2—H2A	0.9600
N4—N5	1.181 (4)	C2—H2B	0.9600
N5—N6	1.140 (4)	C2—H2C	0.9600
N7—N8	1.209 (4)	C3—H3A	0.9600
N8—N9	1.139 (4)	C3—H3B	0.9600
N10—N11	1.225 (4)	C3—H3C	0.9600
N10—Co2ⁱ	2.014 (3)

N7—Co1—N4	88.05 (12)	Co1—N10—Co2ⁱ	121.43 (14)
N7—Co1—N10	91.18 (12)	N12—N11—N10	178.5 (4)
N4—Co1—N10	92.62 (12)	N14—N13—Co1ⁱ	114.1 (2)
N7—Co1—N1	90.55 (12)	N14—N13—Co1	118.0 (2)
N4—Co1—N1	88.97 (12)	Co1ⁱ—N13—Co1	100.22 (11)
N10—Co1—N1	177.69 (12)	N15—N14—N13	178.2 (4)
N7—Co1—N13ⁱ	176.56 (13)	C2—N16—C3	112.7 (4)
N4—Co1—N13ⁱ	94.61 (11)	C2—N16—C1	110.9 (4)
N10—Co1—N13ⁱ	86.53 (11)	C3—N16—C1	111.2 (3)
N1—Co1—N13ⁱ	91.67 (11)	C2—N16—H16	107.3
N7—Co1—N13	97.71 (11)	C3—N16—H16	107.3
N4—Co1—N13	173.16 (12)	C1—N16—H16	107.3
N10—Co1—N13	90.96 (11)	N16—C1—H1A	109.5
N1—Co1—N13	87.29 (11)	N16—C1—H1B	109.5
N13ⁱ—Co1—N13	79.78 (11)	H1A—C1—H1B	109.5
N1ⁱⁱ—Co2—N1	118.61 (16)	N16—C1—H1C	109.5
N1ⁱⁱ—Co2—N10ⁱ	120.58 (11)	H1A—C1—H1C	109.5
N1—Co2—N10ⁱ	97.86 (11)	H1B—C1—H1C	109.5
N1ⁱⁱ—Co2—N10ⁱⁱⁱ	97.86 (11)	N16—C2—H2A	109.5
N1—Co2—N10ⁱⁱⁱ	120.58 (11)	N16—C2—H2B	109.5
N10ⁱ—Co2—N10ⁱⁱⁱ	101.58 (16)	H2A—C2—H2B	109.5
N2—N1—Co2	122.3 (2)	N16—C2—H2C	109.5
N2—N1—Co1	115.0 (2)	H2A—C2—H2C	109.5
Co2—N1—Co1	120.82 (15)	H2B—C2—H2C	109.5
N3—N2—N1	179.9 (5)	N16—C3—H3A	109.5
N5—N4—Co1	119.7 (3)	N16—C3—H3B	109.5
N6—N5—N4	177.2 (4)	H3A—C3—H3B	109.5
N8—N7—Co1	120.8 (2)	N16—C3—H3C	109.5
N9—N8—N7	176.5 (4)	H3A—C3—H3C	109.5
N11—N10—Co1	115.5 (2)	H3B—C3—H3C	109.5
N11—N10—Co2ⁱ	121.6 (2)

Symmetry codes: (i) −x, −y, −z; (ii) −x, y, −z+1/2; (iii) x, −y, z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N16—H16···N7	0.91	2.02	2.890	159

Experimental details

Crystal data
Chemical formula	(C₃H₁₀N)₂[Co₃(N₃)₁₀]
M_r	717.33
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	21.7200 (6), 11.3812 (4), 12.1628 (4)
β (°)	115.524 (2)
V (Å³)	2713.21 (15)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.88
Crystal size (mm)	0.10 × 0.06 × 0.05

Data collection
Diffractometer	Rigaku Saturn
Absorption correction	Multi-scan (REQAB; Jacobson, 1998)
T_min, T_max	0.708, 0.823
No. of measured, independent and observed [I > 2σ(I)] reflections	22049, 2389, 1481
R_int	0.103
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.061, 0.98
No. of reflections	2389
No. of parameters	190
No. of restraints	24
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.31, −0.35

Computer programs: CrystalClear (Rigaku/MSC, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), publCIF (Westrip, 2010).

Selected bond lengths (Å) top

Co1—N7	1.944 (3)	Co1—N13	2.008 (3)
Co1—N4	1.948 (3)	Co2—N1ⁱⁱ	1.968 (3)
Co1—N10	1.964 (3)	Co2—N1	1.968 (3)
Co1—N1	1.979 (3)	Co2—N10ⁱ	2.014 (3)
Co1—N13ⁱ	2.008 (3)	Co2—N10ⁱⁱⁱ	2.014 (3)

Symmetry codes: (i) −x, −y, −z; (ii) −x, y, −z+1/2; (iii) x, −y, z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N16—H16···N7	0.910	2.023	2.890	158.68

Acknowledgements

This study was supported by the Doctoral Research Fund of Henan Chinese Medicine (BSJJ2009–38).

References

Jacobson, R. (1998). REQAB. Private communication to the Rigaku Corporation, Tokyo, Japan. Google Scholar
Liu, T., Yang, Y.-F., Wang, Z.-M. & Gao, S. (2008). Chem. Asian. J. 3, 950–957. Web of Science CrossRef PubMed CAS Google Scholar
Liu, T., Zhang, Y.-J., Wang, Z.-M. & Gao, S. (2006). Inorg. Chem. 45, 2782–2784. Web of Science CSD CrossRef PubMed CAS Google Scholar
Rigaku/MSC (2006). CrystalClear. Rigaku/MSC, The Woodlands, Texas, USA. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar
Zhang, Y.-J., Liu, T., Kanegawa, S. & Sato, O. (2010). J. Am. Chem. Soc. 132, 912–913. Web of Science CSD CrossRef CAS PubMed Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.