1-Benzoyl-3,6-diphenyl-1,4-dihydro-1,2,4,5-tetra­zine

Xu, F.; Yang, Z.-Z.; Chen, X.-F.; Zheng, W.-X.

doi:10.1107/S1600536810038067

organic compounds

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ISSN: 2056-9890

Volume 66| Part 10| October 2010| Page o2664

doi:10.1107/S1600536810038067

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1-Benzoyl-3,6-diphenyl-1,4-dihydro-1,2,4,5-tetrazine

Feng Xu,^a ^* Zhen-Zhen Yang,^a Xiao-Fang Chen ^a and Wen-Xiu Zheng ^a

^aDepartment of Biological and Chemical Engineering, Taizhou Vocational and Technical college, Taizhou 318000, People's Republic of China
^*Correspondence e-mail: xufeng901@126.com

(Received 22 September 2010; accepted 23 September 2010; online 30 September 2010)

In the title compound, C₂₁H₁₆N₄O, the central tetrazine ring adopts an unsymmetrical boat conformation with the two N atoms as the bow and stern. The crystal packing is stabilized by intermolecular N—H—O hydrogen bonds.

Related literature

For related structures, see: Xu et al. (2010 ); Hu et al. (2004 ); Rao et al. (2006 ). For applications of 1,2,4,5-tetrazine derivatives, see: Sauer et al. (1996 ).

Experimental

Crystal data

C₂₁H₁₆N₄O
M_r = 340.38
Orthorhombic, P 2₁ 2₁ 2₁
a = 7.1100 (19) Å
b = 12.115 (3) Å
c = 19.884 (6) Å
V = 1712.7 (8) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 93 K
0.43 × 0.27 × 0.27 mm

Data collection

Rigaku AFC10/Saturn724+ diffractometer
13708 measured reflections
2254 independent reflections
2128 reflections with I > 2σ(I)
R_int = 0.032

Refinement

R[F² > 2σ(F²)] = 0.033
wR(F²) = 0.085
S = 1.00
2254 reflections
239 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N4—H4N⋯O1ⁱ	0.91 (2)	1.97 (2)	2.806 (2)	150.9 (18)
Symmetry code: (i) $[x-{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1]$ .

Data collection: CrystalClear (Rigaku/MSC, 2008 ); 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: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810038067/bq2236sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810038067/bq2236Isup2.hkl

checkCIF report

Comment top

1,2,4,5-Tetrazine derivatives have high potential for biological activity, possessing a wide spectrum of antiviral and antitumor properties. They have been widely used in pesticides and herbicides (Sauer, 1996). Dihydro-1,2,4,5- tetrazine has four isomers, namely 1,2-, 1,4-, 1,6- and 3,6-dihydro-1,2,4,5- tetrazines. The 1,4-dihydro structures (Rao et al., 2006) were found to have potential antitumor properties. In continuation of our work on the structure-activity relationship of dihydro-1,2,4,5-tetrazine derivatives (Hu et al., 2004 & Xu et al., 2010), we report here the crystal structure of the title compound (I) (Fig. 1).

In the tetrazine ring, atoms N2, C3, N5 and C6 are almost coplanar, while atoms N1 and N4 deviate from the plane by 0.447 (2) and 0.330 (2) Å, respectively. The N1/N2/C6 and C3/N4/N5 planes make dihedral angles of 35.76 (2)° and 27.66 (2)°, respectively, with the N2/C3/N5/C6 plane, i.e. the tetrazine ring adopts an unsymmetrical boat conformation. The benzene rings C7—C12, C13—C18 and C20—C25 make dihedral angles of 22.88 (2)°, 17.80 (2)° and 87.09 (2)° with the N2/C3/N5/C6 plane, respectively. Atom N1 is almost sp² hybridized due to the angles around it add up to 358.0 (2)°.

The crystal packing (Fig.2) is stabilized by intermolecular N—H—O interactions between a hydrogen on nitrogen N(4) and the O atom of carbonyl group, with a N—H—O separation of 2.806 (2) Å (Table 2).

Related literature top

For related structures, see: Xu et al. (2010); Hu et al. (2004); Rao et al. (2006). For applications of 1,2,4,5-tetrazine derivatives, see: Sauer et al. (1996).

Experimental top

To a solution of 1,2-dihydro-1,2,4,5-tetrazine (0.47 g, 2 mmol) in chloroform (20 ml) was added dropwise benzoyl chloride (0.28 g, 2 mmol) in chloroform (10 ml) under stirring at room temperature using pyridine (0.17 g, 2.1 mmol) as the catalyst. After stirring for 2 h, the solvent was distilled off under vacuum. The residue was chromatographed on a silica gel column using cyclohexane-dichloromethane (V/V, 1:2) as the eluent to get the yellow solid (0.37 g, 55%). An anhydrous ethanol solution of the title compound was stood at room temperature, and by slowly evaporating ethanol from the solution, yellow crystals suitable for X-ray diffraction analysis were isolated one month later. m.p.: 500–501 K.

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2008); cell refinement: CrystalClear (Rigaku/MSC, 2008); data reduction: CrystalClear (Rigaku/MSC, 2008); 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: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound, showing 30% probability displacement ellipsoids and the atomic numbering.
	Fig. 2. Crystal structure of (I) viewed down the a axis. N—H···O hydrogen bondings are shown as dashed lines.

1-Benzoyl-3,6-diphenyl-1,4-dihydro-1,2,4,5-tetrazine top

Crystal data top

C₂₁H₁₆N₄O	F(000) = 712
M_r = 340.38	D_x = 1.320 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 2254 reflections
a = 7.1100 (19) Å	θ = 3.4–27.5°
b = 12.115 (3) Å	µ = 0.09 mm⁻¹
c = 19.884 (6) Å	T = 93 K
V = 1712.7 (8) Å³	Column, yellow
Z = 4	0.43 × 0.27 × 0.27 mm

Data collection top

Rigaku AFC10/Saturn724+ diffractometer	2128 reflections with I > 2σ(I)
Radiation source: Rotating Anode	R_int = 0.032
Graphite monochromator	θ_max = 27.5°, θ_min = 3.0°
Detector resolution: 28.5714 pixels mm^-1	h = −9→9
ϕ and ω scans	k = −15→14
13708 measured reflections	l = −24→25
2254 independent reflections

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)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.085	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	w = 1/[σ²(F_o²) + (0.0577P)² + 0.196P] where P = (F_o² + 2F_c²)/3
2254 reflections	(Δ/σ)_max = 0.001
239 parameters	Δρ_max = 0.23 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₂₁H₁₆N₄O	V = 1712.7 (8) Å³
M_r = 340.38	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 7.1100 (19) Å	µ = 0.09 mm⁻¹
b = 12.115 (3) Å	T = 93 K
c = 19.884 (6) Å	0.43 × 0.27 × 0.27 mm

Data collection top

Rigaku AFC10/Saturn724+ diffractometer	2128 reflections with I > 2σ(I)
13708 measured reflections	R_int = 0.032
2254 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.033	0 restraints
wR(F²) = 0.085	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	Δρ_max = 0.23 e Å⁻³
2254 reflections	Δρ_min = −0.20 e Å⁻³
239 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
O1	0.41566 (18)	0.55133 (9)	0.57735 (6)	0.0169 (3)
N1	0.1772 (2)	0.56642 (12)	0.50300 (7)	0.0160 (3)
N2	0.1136 (2)	0.55047 (12)	0.43512 (7)	0.0166 (3)
N4	0.0860 (2)	0.74205 (12)	0.44154 (7)	0.0166 (3)
N5	0.0366 (2)	0.74009 (12)	0.50949 (7)	0.0171 (3)
C3	0.0818 (2)	0.64438 (14)	0.40646 (8)	0.0155 (3)
C6	0.0824 (2)	0.65060 (13)	0.53963 (8)	0.0153 (3)
C7	0.0230 (2)	0.62957 (14)	0.60945 (8)	0.0166 (4)
C8	0.0051 (3)	0.52210 (15)	0.63299 (9)	0.0203 (4)
H8	0.0357	0.4620	0.6043	0.024*
C9	−0.0570 (3)	0.50186 (15)	0.69807 (9)	0.0237 (4)
H9	−0.0689	0.4281	0.7137	0.028*
C10	−0.1015 (3)	0.58866 (16)	0.74016 (9)	0.0234 (4)
H10	−0.1438	0.5747	0.7847	0.028*
C11	−0.0842 (3)	0.69637 (16)	0.71726 (9)	0.0230 (4)
H11	−0.1144	0.7561	0.7463	0.028*
C12	−0.0230 (3)	0.71750 (15)	0.65229 (9)	0.0197 (4)
H12	−0.0124	0.7914	0.6368	0.024*
C13	0.0390 (2)	0.64618 (14)	0.33354 (8)	0.0163 (3)
C14	0.1052 (3)	0.55940 (15)	0.29386 (9)	0.0203 (4)
H14	0.1729	0.5004	0.3140	0.024*
C15	0.0725 (3)	0.55907 (16)	0.22504 (9)	0.0225 (4)
H15	0.1169	0.4996	0.1982	0.027*
C16	−0.0250 (3)	0.64547 (16)	0.19537 (9)	0.0217 (4)
H16	−0.0468	0.6453	0.1482	0.026*
C17	−0.0907 (3)	0.73210 (16)	0.23452 (9)	0.0234 (4)
H17	−0.1570	0.7914	0.2141	0.028*
C18	−0.0594 (3)	0.73225 (15)	0.30386 (9)	0.0200 (4)
H18	−0.1054	0.7913	0.3307	0.024*
C19	0.3449 (2)	0.52356 (13)	0.52322 (8)	0.0141 (3)
C20	0.4384 (2)	0.44072 (14)	0.47866 (8)	0.0153 (3)
C21	0.6317 (3)	0.45175 (15)	0.46805 (9)	0.0197 (4)
H21	0.6976	0.5123	0.4872	0.024*
C22	0.7276 (3)	0.37442 (15)	0.42963 (10)	0.0242 (4)
H22	0.8583	0.3833	0.4211	0.029*
C23	0.6319 (3)	0.28419 (16)	0.40369 (9)	0.0221 (4)
H23	0.6978	0.2302	0.3782	0.027*
C24	0.4404 (3)	0.27244 (15)	0.41477 (8)	0.0207 (4)
H24	0.3757	0.2104	0.3969	0.025*
C25	0.3424 (3)	0.35102 (14)	0.45181 (9)	0.0187 (4)
H25	0.2108	0.3435	0.4587	0.022*
H4N	0.048 (3)	0.8053 (17)	0.4209 (10)	0.020 (5)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0209 (6)	0.0155 (6)	0.0144 (5)	−0.0013 (5)	−0.0018 (5)	0.0010 (4)
N1	0.0183 (7)	0.0151 (7)	0.0145 (6)	0.0020 (6)	−0.0008 (6)	−0.0025 (6)
N2	0.0181 (7)	0.0185 (7)	0.0132 (6)	0.0027 (6)	−0.0010 (6)	−0.0031 (6)
N4	0.0226 (7)	0.0142 (7)	0.0129 (6)	0.0022 (6)	0.0006 (6)	−0.0005 (5)
N5	0.0198 (7)	0.0172 (7)	0.0145 (7)	0.0004 (6)	0.0018 (6)	−0.0028 (5)
C3	0.0140 (8)	0.0153 (8)	0.0171 (7)	0.0000 (7)	0.0003 (6)	−0.0029 (6)
C6	0.0164 (8)	0.0126 (8)	0.0170 (8)	0.0012 (7)	−0.0021 (6)	−0.0039 (6)
C7	0.0140 (8)	0.0185 (9)	0.0172 (8)	−0.0001 (7)	−0.0017 (6)	−0.0020 (7)
C8	0.0201 (9)	0.0174 (8)	0.0233 (8)	−0.0022 (7)	0.0023 (7)	−0.0025 (7)
C9	0.0226 (9)	0.0227 (10)	0.0256 (9)	−0.0035 (8)	0.0032 (8)	0.0035 (7)
C10	0.0214 (9)	0.0323 (10)	0.0165 (8)	−0.0013 (8)	0.0031 (7)	0.0020 (7)
C11	0.0239 (9)	0.0273 (10)	0.0179 (8)	0.0037 (8)	0.0005 (7)	−0.0052 (7)
C12	0.0231 (9)	0.0179 (8)	0.0181 (8)	0.0039 (8)	−0.0008 (7)	−0.0019 (7)
C13	0.0141 (8)	0.0184 (8)	0.0162 (7)	−0.0025 (7)	0.0005 (6)	−0.0009 (6)
C14	0.0222 (9)	0.0180 (9)	0.0206 (8)	0.0016 (7)	−0.0017 (7)	−0.0019 (7)
C15	0.0240 (9)	0.0241 (9)	0.0195 (8)	−0.0004 (9)	0.0015 (7)	−0.0060 (7)
C16	0.0200 (8)	0.0303 (10)	0.0148 (7)	−0.0042 (8)	−0.0006 (7)	−0.0006 (7)
C17	0.0235 (9)	0.0256 (10)	0.0210 (8)	0.0022 (8)	−0.0044 (7)	0.0016 (7)
C18	0.0197 (9)	0.0213 (9)	0.0191 (8)	0.0023 (8)	−0.0005 (7)	−0.0023 (7)
C19	0.0173 (8)	0.0108 (7)	0.0143 (7)	−0.0013 (7)	0.0017 (6)	0.0027 (6)
C20	0.0197 (8)	0.0141 (8)	0.0121 (7)	0.0015 (7)	−0.0004 (6)	0.0017 (6)
C21	0.0189 (9)	0.0183 (9)	0.0219 (8)	−0.0006 (7)	−0.0013 (7)	0.0003 (7)
C22	0.0180 (9)	0.0276 (10)	0.0269 (9)	0.0035 (8)	0.0017 (7)	−0.0001 (8)
C23	0.0254 (10)	0.0218 (9)	0.0192 (8)	0.0093 (8)	0.0009 (7)	−0.0007 (7)
C24	0.0262 (9)	0.0162 (8)	0.0197 (8)	0.0018 (8)	−0.0054 (7)	−0.0025 (7)
C25	0.0191 (8)	0.0162 (8)	0.0208 (8)	0.0008 (8)	−0.0011 (7)	−0.0008 (7)

Geometric parameters (Å, º) top

O1—C19	1.235 (2)	C13—C14	1.396 (2)
N1—C19	1.361 (2)	C14—C15	1.388 (2)
N1—C6	1.423 (2)	C14—H14	0.9500
N1—N2	1.4363 (19)	C15—C16	1.387 (3)
N2—C3	1.292 (2)	C15—H15	0.9500
N4—C3	1.374 (2)	C16—C17	1.388 (3)
N4—N5	1.3961 (19)	C16—H16	0.9500
N4—H4N	0.91 (2)	C17—C18	1.397 (2)
N5—C6	1.281 (2)	C17—H17	0.9500
C3—C13	1.482 (2)	C18—H18	0.9500
C6—C7	1.473 (2)	C19—C20	1.495 (2)
C7—C8	1.389 (3)	C20—C25	1.390 (2)
C7—C12	1.403 (2)	C20—C21	1.396 (2)
C8—C9	1.389 (3)	C21—C22	1.388 (3)
C8—H8	0.9500	C21—H21	0.9500
C9—C10	1.381 (3)	C22—C23	1.387 (3)
C9—H9	0.9500	C22—H22	0.9500
C10—C11	1.388 (3)	C23—C24	1.387 (3)
C10—H10	0.9500	C23—H23	0.9500
C11—C12	1.387 (2)	C24—C25	1.391 (3)
C11—H11	0.9500	C24—H24	0.9500
C12—H12	0.9500	C25—H25	0.9500
C13—C18	1.387 (2)

C19—N1—C6	122.48 (14)	C15—C14—H14	119.9
C19—N1—N2	120.12 (13)	C13—C14—H14	119.9
C6—N1—N2	115.36 (14)	C16—C15—C14	120.06 (17)
C3—N2—N1	110.55 (13)	C16—C15—H15	120.0
C3—N4—N5	118.11 (14)	C14—C15—H15	120.0
C3—N4—H4N	119.3 (13)	C15—C16—C17	120.02 (16)
N5—N4—H4N	112.0 (13)	C15—C16—H16	120.0
C6—N5—N4	113.79 (14)	C17—C16—H16	120.0
N2—C3—N4	122.04 (14)	C16—C17—C18	120.08 (18)
N2—C3—C13	118.71 (15)	C16—C17—H17	120.0
N4—C3—C13	119.25 (15)	C18—C17—H17	120.0
N5—C6—N1	119.17 (15)	C13—C18—C17	119.95 (17)
N5—C6—C7	120.97 (15)	C13—C18—H18	120.0
N1—C6—C7	119.61 (15)	C17—C18—H18	120.0
C8—C7—C12	119.05 (16)	O1—C19—N1	120.69 (15)
C8—C7—C6	120.39 (15)	O1—C19—C20	121.22 (15)
C12—C7—C6	120.52 (15)	N1—C19—C20	118.08 (14)
C9—C8—C7	120.56 (17)	C25—C20—C21	120.00 (17)
C9—C8—H8	119.7	C25—C20—C19	122.27 (16)
C7—C8—H8	119.7	C21—C20—C19	117.59 (16)
C10—C9—C8	120.20 (17)	C22—C21—C20	120.15 (18)
C10—C9—H9	119.9	C22—C21—H21	119.9
C8—C9—H9	119.9	C20—C21—H21	119.9
C9—C10—C11	119.80 (16)	C23—C22—C21	119.68 (18)
C9—C10—H10	120.1	C23—C22—H22	120.2
C11—C10—H10	120.1	C21—C22—H22	120.2
C12—C11—C10	120.47 (17)	C24—C23—C22	120.24 (18)
C12—C11—H11	119.8	C24—C23—H23	119.9
C10—C11—H11	119.8	C22—C23—H23	119.9
C11—C12—C7	119.92 (17)	C23—C24—C25	120.37 (18)
C11—C12—H12	120.0	C23—C24—H24	119.8
C7—C12—H12	120.0	C25—C24—H24	119.8
C18—C13—C14	119.71 (15)	C20—C25—C24	119.52 (17)
C18—C13—C3	122.06 (15)	C20—C25—H25	120.2
C14—C13—C3	118.20 (16)	C24—C25—H25	120.2
C15—C14—C13	120.18 (17)

C19—N1—N2—C3	−123.18 (17)	N2—C3—C13—C14	−25.1 (2)
C6—N1—N2—C3	41.0 (2)	N4—C3—C13—C14	155.04 (17)
C3—N4—N5—C6	33.1 (2)	C18—C13—C14—C15	−0.1 (3)
N1—N2—C3—N4	−8.0 (2)	C3—C13—C14—C15	−178.39 (17)
N1—N2—C3—C13	172.13 (14)	C13—C14—C15—C16	0.5 (3)
N5—N4—C3—N2	−30.0 (2)	C14—C15—C16—C17	−0.3 (3)
N5—N4—C3—C13	149.85 (15)	C15—C16—C17—C18	−0.2 (3)
N4—N5—C6—N1	0.9 (2)	C14—C13—C18—C17	−0.4 (3)
N4—N5—C6—C7	−173.36 (15)	C3—C13—C18—C17	177.78 (17)
C19—N1—C6—N5	124.94 (18)	C16—C17—C18—C13	0.6 (3)
N2—N1—C6—N5	−38.8 (2)	C6—N1—C19—O1	5.0 (2)
C19—N1—C6—C7	−60.7 (2)	N2—N1—C19—O1	168.06 (15)
N2—N1—C6—C7	135.50 (16)	C6—N1—C19—C20	−176.05 (15)
N5—C6—C7—C8	154.45 (17)	N2—N1—C19—C20	−13.0 (2)
N1—C6—C7—C8	−19.8 (2)	O1—C19—C20—C25	130.67 (18)
N5—C6—C7—C12	−23.1 (3)	N1—C19—C20—C25	−48.2 (2)
N1—C6—C7—C12	162.63 (17)	O1—C19—C20—C21	−45.1 (2)
C12—C7—C8—C9	−0.1 (3)	N1—C19—C20—C21	136.01 (17)
C6—C7—C8—C9	−177.77 (17)	C25—C20—C21—C22	1.2 (3)
C7—C8—C9—C10	−0.1 (3)	C19—C20—C21—C22	177.08 (16)
C8—C9—C10—C11	0.1 (3)	C20—C21—C22—C23	−2.1 (3)
C9—C10—C11—C12	0.2 (3)	C21—C22—C23—C24	1.4 (3)
C10—C11—C12—C7	−0.5 (3)	C22—C23—C24—C25	0.1 (3)
C8—C7—C12—C11	0.4 (3)	C21—C20—C25—C24	0.3 (3)
C6—C7—C12—C11	178.06 (17)	C19—C20—C25—C24	−175.30 (15)
N2—C3—C13—C18	156.66 (17)	C23—C24—C25—C20	−1.0 (3)
N4—C3—C13—C18	−23.2 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N4—H4N···O1ⁱ	0.91 (2)	1.97 (2)	2.806 (2)	150.9 (18)

Symmetry code: (i) x−1/2, −y+3/2, −z+1.

Experimental details

Crystal data
Chemical formula	C₂₁H₁₆N₄O
M_r	340.38
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	93
a, b, c (Å)	7.1100 (19), 12.115 (3), 19.884 (6)
V (Å³)	1712.7 (8)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.43 × 0.27 × 0.27

Data collection
Diffractometer	Rigaku AFC10/Saturn724+ diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	13708, 2254, 2128
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.085, 1.00
No. of reflections	2254
No. of parameters	239
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.20

Computer programs: CrystalClear (Rigaku/MSC, 2008), 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
N4—H4N···O1ⁱ	0.91 (2)	1.97 (2)	2.806 (2)	150.9 (18)

Symmetry code: (i) x−1/2, −y+3/2, −z+1.

Acknowledgements

We are very grateful to the Science Foundation for Excellent Youth Scholars of the Department of Education of Zhejiang Province and the Educational Commission of Zhejiang Province of China (Y201018289).

References

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