Bis{4,4′-[oxalylbis(aza­nedi­yl)]dipyridinium} octa­molybdate

Qin, J.; Dong, J.; Li, J.; Gong, Y.

doi:10.1107/S1600536810020714

metal-organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 66| Part 7| July 2010| Page m743

doi:10.1107/S1600536810020714

Open

access

Bis{4,4′-[oxalylbis(azanediyl)]dipyridinium} octamolybdate

Jianbo Qin,^a Jingren Dong,^a Jinghua Li ^b and Yun Gong ^a ^*

^aDepartment of Chemistry, College of Chemistry and Chemical Engineering, Chongqing University 400044, People's Republic of China, and ^bDepartment of Pharmaceutical Chemistry, College of Chemistry and Chemical Engineering, Chongqing University 400044, People's Republic of China
^*Correspondence e-mail: gongyun7211@yahoo.com.cn

(Received 24 May 2010; accepted 31 May 2010; online 5 June 2010)

In the crystal structure of the title compound, (C₁₂H₁₂N₄O₂)₂[Mo₈O₂₆], the amino and pyridinium groups of the N¹,N²-di(pyridinium-4-yl)oxalamide cations are hydrogen bonded to the O atoms of the centrosymmetric isopolyoxometalate β-[Mo₈O₂₆]⁴⁻ anions, forming a three-dimensional supramolecular architecture.

Related literature

For polyoxometalates (POMs), see: Cronin et al. (2002 ); Fukaya & Yamase (2003 ); Katsoulis (1988 ); Pope & Müller (1991 ). For the applications of POMs in biology and materials sciences, see: Cui et al. (2003 ); Luan et al. (2002 ); Wang et al. (2003 ). For the structure of N¹,N²-di(pyridin-4-yl)oxalamide, see: Tzeng et al. (2007 ). For details of the geometrical parameters in the same isopolyoxometalate anion, see: Gong et al. (2007 ).

Experimental

Crystal data

(C₁₂H₁₂N₄O₂)₂[Mo₈O₂₆]
M_r = 1672.03
Monoclinic, P 2₁ /c
a = 10.633 (2) Å
b = 11.552 (2) Å
c = 17.240 (4) Å
β = 101.553 (3)°
V = 2074.7 (8) Å³
Z = 2
Mo Kα radiation
μ = 2.45 mm⁻¹
T = 293 K
0.23 × 0.22 × 0.05 mm

Data collection

Siemens SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.829, T_max = 1.000
14669 measured reflections
4534 independent reflections
4215 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.022
wR(F²) = 0.098
S = 1.40
4534 reflections
316 parameters
H-atom parameters constrained
Δρ_max = 1.40 e Å⁻³
Δρ_min = −2.27 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2A⋯O7ⁱ	0.86	2.61	3.368 (4)	148
N1—H1⋯O8ⁱⁱ	0.86	1.89	2.699 (4)	158
N3—H3⋯O5ⁱⁱⁱ	0.86	1.94	2.779 (4)	165
N4—H4A⋯O1	0.86	2.25	2.669 (4)	110
N4—H4A⋯O4^iv	0.86	2.26	3.059 (4)	154
Symmetry codes: (i) x, y, z+1; (ii) $[x, -y+{\script{1\over 2}}, z+{\script{3\over 2}}]$ ; (iii) $[x+1, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (iv) x+1, y-1, z+1.

Data collection: SMART (Siemens, 1996 ); cell refinement: SAINT (Siemens, 1996); 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: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810020714/su2182sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810020714/su2182Isup2.hkl

checkCIF report

Comment top

Polyoxometalates (POMs) are early transition metal oxygen anion clusters. They are an outstanding class of anionic compounds due to their wealthy topology, superior physical and chemical properties (Pope & Muller, 1991; Katsoulis, 1988). The nanoscopic sizes (Cronin, et al., 2002; Fukaya & Yamase, 2003,) and thier diversified shapes of discrete POMs have attracted great interest. The design, synthesis and structural characterization of inorganic-organic hybrid compounds base on POMs, for which many properties and applications can be predicted, have established a new field of research in the chemistry of biology and materials sciences (Luan, et al., 2002; Cui, et al., 2003; Wang, et al., 2003). Different N-heterocycle ligands can lead to different inorganic-organic hybrid compounds based on POMs. N¹,N²-di(pyridin-4-yl)oxalamide (L), is a bis-pyridine ligand, which has been reported only rarely in the construction of hybrid compounds based on POMs. In the present work, the title complex was synthesized hydrothermally by reacting L with the isopolyoxometalate, Mo₈O₂₆.

The molecular structure of the title complex is illustrated in Fig. 1. In the asymmetric unit there is a doublely protonated L molecule, and half an isopolyoxometalate unit. The bond distances and angles in the cation are similar to those observed previously for N¹,N²-di(pyridin-4-yl)oxalamide (Tzeng, et al., 2007). For the anion, [Mo₈O₂₆]^4-, the geometrical parameters are similar to those reported by (Gong, et al., 2007).

In the crystal the protonated pyrdidinium groups and the amino group form N-H···O hydrogen bonds with the oxygen atoms of the centrosymmetric [Mo₈O₂₆]^4- anions, leading to the formation of a three dimensional supramolecular network (Table 1 and Fig. 2).

Related literature top

For polyoxometalates (POMs), see: Cronin et al. (2002); Fukaya & Yamase (2003); Katsoulis (1988); Pope & Muller (1991). For the applications of POMs in the chemistry of biology and materials sciences, see: Cui et al. (2003); Luan et al. (2002); Wang et al. (2003). For the structure of N¹,N²-di(pyridin-4-yl)oxalamide, see: Tzeng et al. (2007). For details of the geometrical parameters in the same isopolyoxometalate anion, see: Gong et al. (2007).

Experimental top

A mixture of L (0.05 mmol, 0.012 g), Na₂MoO₄(0.05 mmol, 0.012 g) and water(10 ml) was adjusted to pH = 3.0 by HCl. The synthesis was carried out hydrothermally using a Teflon-lined autoclave. The reaction mixture was heated at 393 K for 3 days, followed by slow cooling to rt. The resulting colorless prismatic crystals were filtered off and washed with water (yield: ca. 90% based on Mo). Elemental analyse - found: C, 17.45; H, 1.58; N, 6.56; Mo, 46.11; calcd: C, 17.22; H, 1.44; N, 6.70; Mo, 45.93.

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); 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: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title complex, with the atomic numbering scheme and displacement ellipsoids at the 30% probability level [Symmetry codes: (i) -x,-y+1,-z].
	Fig. 2. A view along the b-axis of the crystal packing of the title complex, illustrating the three dimensional supramolecular architecture constructed by the intermolecular N-H···O hydrogen bonds (dotted lines); see Table 1 for details.

Bis{4,4'-[oxalylbis(azanediyl)]dipyridinium} octamolybdate top

Crystal data top

(C₁₂H₁₂N₄O₂)₂[Mo₈O₂₆]	F(000) = 1592
M_r = 1672.03	D_x = 2.670 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5569 reflections
a = 10.633 (2) Å	θ = 2.1–27.5°
b = 11.552 (2) Å	µ = 2.45 mm⁻¹
c = 17.240 (4) Å	T = 293 K
β = 101.553 (3)°	Prism, colorless
V = 2074.7 (8) Å³	0.23 × 0.22 × 0.05 mm
Z = 2

Data collection top

Siemens CCD area-detector diffractometer	4534 independent reflections
Radiation source: fine-focus sealed tube	4215 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
ϕ and ω scans	θ_max = 27.5°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −13→13
T_min = 0.829, T_max = 1.000	k = −13→14
14669 measured reflections	l = −22→17

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)] = 0.022	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.098	H-atom parameters constrained
S = 1.40	w = 1/[σ²(F_o²) + (0.054P)² + 0.4946P] where P = (F_o² + 2F_c²)/3
4534 reflections	(Δ/σ)_max = 0.001
316 parameters	Δρ_max = 1.40 e Å⁻³
0 restraints	Δρ_min = −2.27 e Å⁻³

Crystal data top

(C₁₂H₁₂N₄O₂)₂[Mo₈O₂₆]	V = 2074.7 (8) Å³
M_r = 1672.03	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 10.633 (2) Å	µ = 2.45 mm⁻¹
b = 11.552 (2) Å	T = 293 K
c = 17.240 (4) Å	0.23 × 0.22 × 0.05 mm
β = 101.553 (3)°

Data collection top

Siemens CCD area-detector diffractometer	4534 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	4215 reflections with I > 2σ(I)
T_min = 0.829, T_max = 1.000	R_int = 0.021
14669 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.022	0 restraints
wR(F²) = 0.098	H-atom parameters constrained
S = 1.40	Δρ_max = 1.40 e Å⁻³
4534 reflections	Δρ_min = −2.27 e Å⁻³
316 parameters

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Mo1	0.08119 (2)	0.53770 (2)	0.098624 (15)	0.01481 (10)
Mo2	0.03951 (3)	0.71904 (2)	−0.069243 (16)	0.01713 (10)
Mo3	0.25513 (2)	0.49409 (2)	−0.029720 (16)	0.01602 (10)
Mo4	−0.13294 (3)	0.77083 (2)	0.064661 (17)	0.01917 (10)
O12	0.0104 (2)	0.8099 (2)	0.01704 (14)	0.0218 (5)
O6	0.2011 (2)	0.4893 (2)	0.17096 (15)	0.0252 (5)
O15	0.1779 (2)	0.61483 (18)	0.02814 (13)	0.0168 (4)
O5	−0.0636 (2)	0.44017 (19)	0.11312 (13)	0.0165 (4)
O4	−0.2513 (2)	0.8238 (2)	−0.00841 (16)	0.0297 (6)
O7	0.3709 (2)	0.4459 (2)	0.04628 (15)	0.0275 (5)
N2	0.5229 (3)	0.1925 (2)	1.09498 (17)	0.0221 (6)
H2A	0.5102	0.2587	1.0720	0.026*
O13	0.0261 (2)	0.6628 (2)	0.13799 (13)	0.0205 (5)
C2	0.3935 (3)	0.2606 (3)	1.1832 (2)	0.0259 (7)
H2	0.3675	0.3224	1.1491	0.031*
O11	0.3343 (2)	0.5745 (2)	−0.08718 (14)	0.0242 (5)
O9	−0.0852 (3)	0.7563 (2)	−0.14308 (15)	0.0274 (5)
O10	0.1691 (3)	0.7832 (2)	−0.09476 (16)	0.0273 (5)
C5	0.4718 (4)	0.0833 (3)	1.2863 (2)	0.0301 (8)
H5	0.4985	0.0245	1.3227	0.036*
C4	0.5210 (4)	0.0892 (3)	1.2190 (2)	0.0265 (7)
H4	0.5801	0.0346	1.2091	0.032*
N1	0.3858 (3)	0.1609 (3)	1.30054 (17)	0.0280 (7)
H1	0.3545	0.1541	1.3426	0.034*
O3	−0.1253 (3)	0.8654 (2)	0.14042 (16)	0.0321 (6)
C3	0.4805 (3)	0.1793 (3)	1.16520 (18)	0.0196 (6)
C1	0.3471 (4)	0.2490 (3)	1.2508 (2)	0.0286 (8)
H1A	0.2882	0.3025	1.2626	0.034*
O14	0.0844 (2)	0.40727 (19)	0.01120 (12)	0.0173 (4)
O8	0.2273 (2)	0.3590 (2)	−0.09586 (13)	0.0205 (5)
N3	0.8440 (3)	0.0969 (3)	0.75088 (17)	0.0285 (7)
H3	0.8761	0.0988	0.7089	0.034*
O2	0.5624 (3)	0.2419 (2)	0.94778 (15)	0.0289 (6)
O1	0.6119 (3)	0.0145 (2)	1.08260 (16)	0.0334 (6)
N4	0.6865 (3)	0.0776 (3)	0.94989 (17)	0.0236 (6)
H4A	0.7065	0.0154	0.9770	0.028*
C11	0.7132 (3)	0.1824 (3)	0.8303 (2)	0.0261 (7)
H11	0.6606	0.2428	0.8399	0.031*
C10	0.7680 (4)	0.1841 (3)	0.7648 (2)	0.0298 (8)
H10	0.7525	0.2461	0.7297	0.036*
C8	0.8193 (4)	0.0012 (3)	0.8668 (2)	0.0303 (8)
H8	0.8384	−0.0609	0.9015	0.036*
C9	0.8712 (4)	0.0072 (3)	0.8005 (2)	0.0333 (9)
H9	0.9256	−0.0512	0.7898	0.040*
C12	0.7373 (3)	0.0892 (3)	0.88212 (18)	0.0204 (6)
C6	0.5830 (3)	0.1107 (3)	1.05882 (19)	0.0206 (6)
C7	0.6084 (3)	0.1539 (3)	0.97837 (19)	0.0226 (7)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Mo1	0.01333 (15)	0.02061 (16)	0.01084 (15)	−0.00116 (9)	0.00325 (10)	−0.00091 (10)
Mo2	0.01807 (16)	0.01867 (16)	0.01602 (16)	0.00122 (10)	0.00673 (11)	0.00088 (10)
Mo3	0.01266 (15)	0.02166 (17)	0.01468 (16)	0.00069 (9)	0.00496 (11)	0.00006 (10)
Mo4	0.01891 (17)	0.02088 (16)	0.01936 (16)	0.00103 (10)	0.00773 (12)	−0.00038 (10)
O12	0.0232 (12)	0.0214 (11)	0.0228 (11)	−0.0027 (9)	0.0093 (10)	−0.0038 (9)
O6	0.0216 (12)	0.0342 (13)	0.0184 (12)	0.0020 (10)	0.0003 (10)	0.0029 (10)
O15	0.0156 (10)	0.0194 (10)	0.0160 (10)	−0.0018 (8)	0.0047 (8)	−0.0007 (9)
O5	0.0162 (10)	0.0199 (10)	0.0146 (10)	0.0006 (8)	0.0057 (8)	0.0005 (9)
O4	0.0250 (13)	0.0339 (14)	0.0311 (14)	0.0052 (11)	0.0073 (11)	0.0089 (11)
O7	0.0216 (12)	0.0381 (14)	0.0221 (12)	0.0048 (11)	0.0026 (10)	0.0052 (11)
N2	0.0260 (15)	0.0251 (14)	0.0176 (13)	0.0021 (12)	0.0105 (11)	0.0042 (11)
O13	0.0204 (11)	0.0226 (11)	0.0192 (11)	−0.0004 (9)	0.0059 (9)	−0.0040 (9)
C2	0.0268 (18)	0.0300 (17)	0.0226 (17)	0.0055 (14)	0.0089 (14)	0.0044 (14)
O11	0.0217 (12)	0.0292 (12)	0.0237 (12)	−0.0022 (10)	0.0091 (10)	0.0032 (10)
O9	0.0291 (13)	0.0281 (12)	0.0232 (12)	0.0072 (11)	0.0010 (11)	0.0008 (11)
O10	0.0272 (13)	0.0269 (13)	0.0305 (13)	−0.0026 (10)	0.0127 (11)	0.0019 (10)
C5	0.038 (2)	0.0303 (18)	0.0222 (17)	0.0010 (16)	0.0069 (15)	0.0068 (15)
C4	0.0269 (18)	0.0316 (18)	0.0222 (17)	0.0038 (14)	0.0074 (14)	0.0026 (15)
N1	0.0295 (16)	0.0401 (17)	0.0171 (13)	−0.0029 (13)	0.0114 (12)	−0.0004 (13)
O3	0.0354 (14)	0.0310 (13)	0.0332 (14)	0.0015 (11)	0.0146 (12)	−0.0097 (12)
C3	0.0180 (15)	0.0268 (16)	0.0148 (14)	−0.0016 (12)	0.0053 (12)	0.0005 (13)
C1	0.0263 (18)	0.0380 (19)	0.0235 (17)	0.0048 (15)	0.0097 (15)	−0.0007 (16)
O14	0.0169 (10)	0.0209 (10)	0.0153 (10)	0.0003 (8)	0.0063 (8)	0.0001 (9)
O8	0.0223 (11)	0.0228 (11)	0.0193 (11)	0.0002 (9)	0.0110 (9)	−0.0029 (9)
N3	0.0311 (16)	0.0405 (17)	0.0173 (13)	−0.0040 (14)	0.0130 (12)	−0.0015 (13)
O2	0.0333 (14)	0.0309 (13)	0.0244 (13)	0.0054 (11)	0.0104 (11)	0.0031 (11)
O1	0.0461 (17)	0.0300 (14)	0.0293 (14)	0.0072 (12)	0.0204 (13)	0.0039 (11)
N4	0.0278 (15)	0.0276 (14)	0.0188 (13)	0.0042 (12)	0.0127 (12)	0.0029 (12)
C11	0.0261 (17)	0.0322 (18)	0.0218 (16)	0.0051 (14)	0.0090 (14)	0.0019 (14)
C10	0.0299 (19)	0.040 (2)	0.0209 (17)	0.0027 (16)	0.0074 (15)	0.0061 (15)
C8	0.040 (2)	0.0269 (18)	0.0284 (19)	0.0052 (15)	0.0175 (17)	0.0041 (15)
C9	0.042 (2)	0.0317 (19)	0.032 (2)	−0.0007 (16)	0.0210 (18)	−0.0033 (16)
C12	0.0232 (16)	0.0244 (16)	0.0155 (14)	−0.0036 (13)	0.0081 (12)	−0.0026 (12)
C6	0.0195 (15)	0.0278 (16)	0.0171 (14)	−0.0042 (13)	0.0094 (12)	−0.0017 (13)
C7	0.0235 (16)	0.0286 (16)	0.0172 (15)	−0.0049 (14)	0.0076 (13)	−0.0018 (14)

Geometric parameters (Å, º) top

Mo1—O6	1.690 (2)	C2—C3	1.395 (5)
Mo1—O13	1.747 (2)	C2—H2	0.9300
Mo1—O15	1.956 (2)	C5—N1	1.338 (5)
Mo1—O5	1.964 (2)	C5—C4	1.366 (5)
Mo1—O14	2.136 (2)	C5—H5	0.9300
Mo1—O14ⁱ	2.399 (2)	C4—C3	1.403 (5)
Mo1—Mo3	3.1951 (6)	C4—H4	0.9300
Mo2—O10	1.699 (3)	N1—C1	1.342 (5)
Mo2—O9	1.699 (3)	N1—H1	0.8600
Mo2—O12	1.896 (2)	C1—H1A	0.9300
Mo2—O5ⁱ	2.024 (2)	O14—Mo2ⁱ	2.322 (2)
Mo2—O14ⁱ	2.322 (2)	O14—Mo1ⁱ	2.399 (2)
Mo2—O15	2.333 (2)	O8—Mo4ⁱ	1.939 (2)
Mo3—O11	1.699 (2)	N3—C9	1.338 (5)
Mo3—O7	1.702 (2)	N3—C10	1.342 (5)
Mo3—O8	1.921 (2)	N3—H3	0.8600
Mo3—O15	1.986 (2)	O2—C7	1.203 (4)
Mo3—O14	2.305 (2)	O1—C6	1.203 (4)
Mo3—O5ⁱ	2.370 (2)	N4—C7	1.368 (4)
Mo4—O3	1.692 (3)	N4—C12	1.388 (4)
Mo4—O4	1.706 (3)	N4—H4A	0.8600
Mo4—O12	1.924 (2)	C11—C10	1.371 (5)
Mo4—O8ⁱ	1.939 (2)	C11—C12	1.390 (5)
Mo4—O13	2.271 (2)	C11—H11	0.9300
O5—Mo2ⁱ	2.024 (2)	C10—H10	0.9300
O5—Mo3ⁱ	2.370 (2)	C8—C9	1.368 (5)
N2—C6	1.360 (4)	C8—C12	1.398 (5)
N2—C3	1.383 (4)	C8—H8	0.9300
N2—H2A	0.8600	C9—H9	0.9300
C2—C1	1.361 (5)	C6—C7	1.548 (5)

O6—Mo1—O13	104.42 (12)	O12—Mo4—O13	78.54 (10)
O6—Mo1—O15	101.34 (11)	O8ⁱ—Mo4—O13	77.86 (9)
O13—Mo1—O15	97.08 (10)	Mo2—O12—Mo4	118.21 (12)
O6—Mo1—O5	102.18 (11)	Mo1—O15—Mo3	108.29 (10)
O13—Mo1—O5	95.32 (10)	Mo1—O15—Mo2	110.37 (10)
O15—Mo1—O5	149.67 (9)	Mo3—O15—Mo2	105.41 (9)
O6—Mo1—O14	99.85 (11)	Mo1—O5—Mo2ⁱ	108.21 (10)
O13—Mo1—O14	155.72 (10)	Mo1—O5—Mo3ⁱ	109.83 (10)
O15—Mo1—O14	78.37 (9)	Mo2ⁱ—O5—Mo3ⁱ	102.84 (9)
O5—Mo1—O14	78.98 (9)	C6—N2—C3	126.2 (3)
O6—Mo1—O14ⁱ	174.94 (10)	C6—N2—H2A	116.9
O13—Mo1—O14ⁱ	80.62 (9)	C3—N2—H2A	116.9
O15—Mo1—O14ⁱ	77.46 (8)	Mo1—O13—Mo4	120.57 (11)
O5—Mo1—O14ⁱ	77.42 (8)	C1—C2—C3	119.6 (3)
O14—Mo1—O14ⁱ	75.11 (9)	C1—C2—H2	120.2
O6—Mo1—Mo3	90.19 (9)	C3—C2—H2	120.2
O13—Mo1—Mo3	133.25 (8)	N1—C5—C4	121.0 (3)
O15—Mo1—Mo3	36.17 (6)	N1—C5—H5	119.5
O5—Mo1—Mo3	125.10 (6)	C4—C5—H5	119.5
O14—Mo1—Mo3	46.13 (6)	C5—C4—C3	118.6 (3)
O14ⁱ—Mo1—Mo3	86.01 (5)	C5—C4—H4	120.7
O10—Mo2—O9	104.31 (13)	C3—C4—H4	120.7
O10—Mo2—O12	103.29 (11)	C5—N1—C1	121.6 (3)
O9—Mo2—O12	102.84 (11)	C5—N1—H1	119.2
O10—Mo2—O5ⁱ	97.46 (11)	C1—N1—H1	119.2
O9—Mo2—O5ⁱ	95.06 (11)	N2—C3—C2	117.9 (3)
O12—Mo2—O5ⁱ	148.09 (10)	N2—C3—C4	123.3 (3)
O10—Mo2—O14ⁱ	160.99 (11)	C2—C3—C4	118.8 (3)
O9—Mo2—O14ⁱ	93.28 (11)	N1—C1—C2	120.3 (3)
O12—Mo2—O14ⁱ	79.28 (9)	N1—C1—H1A	119.8
O5ⁱ—Mo2—O14ⁱ	73.47 (8)	C2—C1—H1A	119.8
O10—Mo2—O15	89.10 (11)	Mo1—O14—Mo3	91.94 (8)
O9—Mo2—O15	162.69 (11)	Mo1—O14—Mo2ⁱ	92.79 (8)
O12—Mo2—O15	84.24 (9)	Mo3—O14—Mo2ⁱ	162.71 (11)
O5ⁱ—Mo2—O15	72.02 (8)	Mo1—O14—Mo1ⁱ	104.89 (9)
O14ⁱ—Mo2—O15	72.31 (8)	Mo3—O14—Mo1ⁱ	98.15 (8)
O11—Mo3—O7	105.16 (12)	Mo2ⁱ—O14—Mo1ⁱ	96.69 (8)
O11—Mo3—O8	97.69 (11)	Mo3—O8—Mo4ⁱ	119.38 (11)
O7—Mo3—O8	101.11 (12)	C9—N3—C10	121.9 (3)
O11—Mo3—O15	102.23 (11)	C9—N3—H3	119.1
O7—Mo3—O15	98.71 (11)	C10—N3—H3	119.1
O8—Mo3—O15	147.03 (9)	C7—N4—C12	127.3 (3)
O11—Mo3—O14	158.28 (10)	C7—N4—H4A	116.3
O7—Mo3—O14	96.57 (11)	C12—N4—H4A	116.3
O8—Mo3—O14	77.93 (9)	C10—C11—C12	119.1 (3)
O15—Mo3—O14	73.83 (8)	C10—C11—H11	120.4
O11—Mo3—O5ⁱ	86.39 (10)	C12—C11—H11	120.4
O7—Mo3—O5ⁱ	166.64 (10)	N3—C10—C11	120.4 (3)
O8—Mo3—O5ⁱ	83.62 (9)	N3—C10—H10	119.8
O15—Mo3—O5ⁱ	71.82 (8)	C11—C10—H10	119.8
O14—Mo3—O5ⁱ	72.03 (8)	C9—C8—C12	119.5 (3)
O11—Mo3—Mo1	137.78 (9)	C9—C8—H8	120.3
O7—Mo3—Mo1	87.02 (9)	C12—C8—H8	120.3
O8—Mo3—Mo1	119.84 (7)	N3—C9—C8	120.1 (4)
O15—Mo3—Mo1	35.55 (6)	N3—C9—H9	119.9
O14—Mo3—Mo1	41.93 (5)	C8—C9—H9	119.9
O5ⁱ—Mo3—Mo1	79.83 (5)	N4—C12—C11	124.3 (3)
O3—Mo4—O4	104.63 (14)	N4—C12—C8	116.8 (3)
O3—Mo4—O12	104.98 (12)	C11—C12—C8	118.9 (3)
O4—Mo4—O12	97.54 (12)	O1—C6—N2	126.7 (3)
O3—Mo4—O8ⁱ	103.44 (11)	O1—C6—C7	121.6 (3)
O4—Mo4—O8ⁱ	97.81 (12)	N2—C6—C7	111.6 (3)
O12—Mo4—O8ⁱ	142.92 (9)	O2—C7—N4	127.6 (3)
O3—Mo4—O13	90.56 (11)	O2—C7—C6	122.5 (3)
O4—Mo4—O13	164.80 (11)	N4—C7—C6	110.0 (3)

Symmetry code: (i) −x, −y+1, −z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···O7ⁱⁱ	0.86	2.61	3.368 (4)	148
N1—H1···O8ⁱⁱⁱ	0.86	1.89	2.699 (4)	158
N3—H3···O5^iv	0.86	1.94	2.779 (4)	165
N4—H4A···O1	0.86	2.25	2.669 (4)	110
N4—H4A···O4^v	0.86	2.26	3.059 (4)	154

Symmetry codes: (ii) x, y, z+1; (iii) x, −y+1/2, z+3/2; (iv) x+1, −y+1/2, z+1/2; (v) x+1, y−1, z+1.

Experimental details

Crystal data
Chemical formula	(C₁₂H₁₂N₄O₂)₂[Mo₈O₂₆]
M_r	1672.03
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	10.633 (2), 11.552 (2), 17.240 (4)
β (°)	101.553 (3)
V (Å³)	2074.7 (8)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	2.45
Crystal size (mm)	0.23 × 0.22 × 0.05

Data collection
Diffractometer	Siemens CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.829, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	14669, 4534, 4215
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.022, 0.098, 1.40
No. of reflections	4534
No. of parameters	316
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.40, −2.27

Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···O7ⁱ	0.86	2.608	3.368 (4)	148
N1—H1···O8ⁱⁱ	0.86	1.885	2.699 (4)	158
N3—H3···O5ⁱⁱⁱ	0.86	1.940	2.779 (4)	165
N4—H4A···O1	0.86	2.248	2.669 (4)	110
N4—H4A···O4^iv	0.86	2.263	3.059 (4)	154

Symmetry codes: (i) x, y, z+1; (ii) x, −y+1/2, z+3/2; (iii) x+1, −y+1/2, z+1/2; (iv) x+1, y−1, z+1.

Acknowledgements

This work was supported by the Chongqing University Postgraduate Science Fund (No. 200911A1B0010317) and the Fundamental Research Funds for the Central Universities (No. CDJZR10 22 00 09)

References

Cronin, L., Beugholt, C., Krickemeyer, E., Schmidtmann, M., Bogge, H., Kogerler, P., Luong, T. K. K. & Müller, A. (2002). Angew. Chem. Int. Ed. 41, 2805–2808. CrossRef CAS Google Scholar
Cui, X. B., Xu, J. Q., Li, Y., Sun, Y. H., Ye, L. & Yang, G. Y. (2003). J. Mol. Struct. 657, 397–403. CSD CrossRef CAS Google Scholar
Fukaya, K. & Yamase, T. (2003). Angew. Chem. Int. Ed. 42, 6544–658. Web of Science CrossRef Google Scholar
Gong, Y., Hu, C. W. & Xia, Z. N. (2007). J. Mol. Struct. 837, 48–57. Web of Science CSD CrossRef CAS Google Scholar
Katsoulis, D. E. (1988). Chem. Rev. 90, 359–387. Google Scholar
Luan, G. Y., Wang, E. B., Han, Z. B., Li, Y. G., Hu, C. W., Hu, N. H. & Jia, H. Q. (2002). J. Mol. Struct. 606, 211–215. Web of Science CSD CrossRef CAS Google Scholar
Pope, M. T. & Müller, A. (1991). Angew. Chem. Int. Ed. 30, 34–48. CrossRef Web of Science Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA. Google Scholar
Tzeng, B. C., Chen, Y. F., Wu, C. C., Hu, C. C., Chang, Y. T. & Chen, C. K. (2007). New J. Chem. 31, 202–209. Web of Science CSD CrossRef CAS Google Scholar
Wang, D. R., Zhang, W. J., Gruning, K. & Rehder, D. (2003). J. Mol. Struct. 656, 79–91. Web of Science CrossRef CAS Google Scholar