N-(2-Chloro-2-nitro-1-phenyl­prop­yl)-4-methyl­benzene­sulfonamide

Zhi, S.; Li, T.; An, G.; Pan, Y.

doi:10.1107/S1600536807067712

organic compounds

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ISSN: 2056-9890

Volume 64| Part 2| February 2008| Page o357

doi:10.1107/S1600536807067712

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N-(2-Chloro-2-nitro-1-phenylpropyl)-4-methylbenzenesulfonamide

Sanjun Zhi,^a Tengfei Li,^a Guanghui An ^a and Yi Pan ^a ^*

^aSchool of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093, People's Republic of China
^*Correspondence e-mail: jchyzhi2003@126.com

(Received 29 November 2007; accepted 19 December 2007; online 4 January 2008)

In the title compound, C₁₆H₁₇ClN₂O₄S, the dihedral angle between the phenyl and benzene rings is 19.4 (2)°. The crystal packing is stabilized by intermolecular N—H⋯O hydrogen bonds, as well as by intra- and intermolecular C—H⋯O hydrogen bonds.

Related literature

For general background, see Kemp (1991 ); Qui & Silverman (2000 ); Orlek & Stemp (1991 ), Han et al. (2007 ); Li et al. (2007 ). For bond-length data, see: Allen et al. (1987 ).

Experimental

Crystal data

C₁₆H₁₇ClN₂O₄S
M_r = 368.83
Orthorhombic, P b c a
a = 7.8254 (8) Å
b = 19.610 (2) Å
c = 22.533 (3) Å
V = 3457.8 (7) Å³
Z = 8
Mo Kα radiation
μ = 0.36 mm⁻¹
T = 291 (2) K
0.30 × 0.26 × 0.24 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000 ) T_min = 0.901, T_max = 0.921
17527 measured reflections
3396 independent reflections
2467 reflections with I > 2σ(I)
R_int = 0.070

Refinement

R[F² > 2σ(F²)] = 0.056
wR(F²) = 0.125
S = 1.01
3396 reflections
222 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.26 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3—H3⋯O1	0.98	2.46	2.933 (4)	109
C3—H3⋯O3	0.98	2.42	2.779 (4)	101
C1—H1A⋯O2ⁱ	0.96	2.52	3.369 (4)	147
C1—H1B⋯O1ⁱⁱ	0.96	2.58	3.310 (4)	133
N2—H2A⋯O2ⁱ	0.89 (2)	2.32 (3)	3.141 (3)	153
Symmetry codes: (i) $[x+{\script{1\over 2}}, y, -z+{\script{3\over 2}}]$ ; (ii) x+1, y, z.

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Bruker, 2000); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536807067712/at2518sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536807067712/at2518Isup2.hkl

checkCIF report

Comment top

Since the vicinal haloamines are important building blocks in organic and medicinal chemistry, many attentions are attracted to the aminohalogenation reactions of functionalized alkenes (Kemp, 1991; Qui & Silverman, 2000). In recent years, many new aminohalogenation processes of several kinds of functionalized alkenes have been developed (Han et al., 2007), with the different nitrogen/halogen sources in the presence of metallic catalysts (Li et al., 2007). However, the aminohalogenation reactions of 2-nitro-propenyl benzene was not been well documented. Recently, we synthesized the title compound (I) from 2-nitro-propenyl benzene. As part of this study, we have undertaken the X-ray crystallographic analysis of (I) in order to elucidate the conformation and configuration of this product.

The bond lengths and angles in (I) are in good agree with expected values (Allen et al., 1987). The dihedral angle between the phenyl and benzene rings is 19.4 (2)°. The packing is stabilized by intermolecular N—H···O as well as intra and intermolecular C—H···O interactions in the crystal structure (Table 1).

Related literature top

For general background, see Kemp (1991); Qui & Silverman (2000); Orlek & Stemp (1991), Han et al. (2007); Li et al. (2007). For bond-length data, see: Allen et al. (1987).

Experimental top

N-cChlorosuccinimide (400 mg, 3.0 mmol) was added into a solution of MnSO₄ (30.2 mg, 0.20 mmol), 1-benzyl-2-nitro-propene (163 mg, 1 mmol), tolunesulfonamide (513 mg, 3 mmol) and 4 Å molecular sieves (500 mg) in CH₂Cl₂ (5.0 ml) with nitrogen atmosphere. The resulting mixture was stirred at room temperature for 48 h. Reaction was quenched with saturated aqueous Na₂S₂O₃ solution. The solid precipitates were filtered off and washed with ethyl acetate (3 × 10 ml). The organic solution was concentrated and then purified via flash chromatography (ethyl acetate/ hexane, 1:4, v/v) provide the title compound (I) as white solid (276 mg) in yield of 75%. A colourless crystal of (I) for X-ray analysis was obtained by slow evaporation from ethyl acetate solution system.

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SMART (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXTL (Bruker, 2000); program(s) used to refine structure: SHELXTL (Bruker, 2000); molecular graphics: SHELXTL (Bruker, 2000); software used to prepare material for publication: SHELXTL (Bruker, 2000) and PLATON (Spek, 2003).

Figures top

Fig. 1. The molecular structure of (I), with atom labels and 30% probability displacement ellipsoids for non-H atoms.

N-(2-Chloro-2-nitro-1-phenylpropyl)-4-methylbenzenesulfonamide top

Crystal data top

C₁₆H₁₇ClN₂O₄S	D_x = 1.417 Mg m⁻³
M_r = 368.83	Melting point: 423.2 K
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 7468 reflections
a = 7.8254 (8) Å	θ = 2.3–27.9°
b = 19.610 (2) Å	µ = 0.36 mm⁻¹
c = 22.533 (3) Å	T = 291 K
V = 3457.8 (7) Å³	Block, colourless
Z = 8	0.30 × 0.26 × 0.24 mm
F(000) = 1536

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	3396 independent reflections
Radiation source: sealed tube	2467 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.070
ϕ and ω scans	θ_max = 26.0°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −9→8
T_min = 0.901, T_max = 0.921	k = −24→24
17527 measured reflections	l = −16→27

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)] = 0.056	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.125	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	w = 1/[σ²(F_o²) + (0.06P)² + 0.58P] where P = (F_o² + 2F_c²)/3
3396 reflections	(Δ/σ)_max < 0.001
222 parameters	Δρ_max = 0.28 e Å⁻³
0 restraints	Δρ_min = −0.26 e Å⁻³

Crystal data top

C₁₆H₁₇ClN₂O₄S	V = 3457.8 (7) Å³
M_r = 368.83	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 7.8254 (8) Å	µ = 0.36 mm⁻¹
b = 19.610 (2) Å	T = 291 K
c = 22.533 (3) Å	0.30 × 0.26 × 0.24 mm

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	3396 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2000)	2467 reflections with I > 2σ(I)
T_min = 0.901, T_max = 0.921	R_int = 0.070
17527 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.056	0 restraints
wR(F²) = 0.125	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	Δρ_max = 0.28 e Å⁻³
3396 reflections	Δρ_min = −0.26 e Å⁻³
222 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
C1	0.7916 (4)	0.10320 (17)	0.61740 (13)	0.0374 (7)
H1A	0.7709	0.1030	0.6594	0.056*
H1B	0.8606	0.1420	0.6072	0.056*
H1C	0.8503	0.0621	0.6064	0.056*
C2	0.6185 (4)	0.10723 (16)	0.58376 (13)	0.0333 (7)
C3	0.5059 (4)	0.16923 (14)	0.59888 (13)	0.0292 (6)
H3	0.3995	0.1645	0.5763	0.035*
C4	0.5853 (3)	0.23727 (15)	0.58138 (13)	0.0293 (6)
C5	0.5405 (4)	0.26704 (17)	0.52790 (13)	0.0362 (7)
H5	0.4651	0.2445	0.5028	0.043*
C6	0.6055 (4)	0.32954 (17)	0.51103 (14)	0.0415 (8)
H6	0.5765	0.3484	0.4745	0.050*
C7	0.7156 (4)	0.36407 (18)	0.54968 (15)	0.0437 (8)
H7	0.7570	0.4070	0.5396	0.052*
C8	0.7623 (4)	0.33466 (18)	0.60226 (15)	0.0444 (8)
H8	0.8381	0.3572	0.6273	0.053*
C9	0.6972 (4)	0.27113 (17)	0.61859 (14)	0.0414 (8)
H9	0.7290	0.2516	0.6545	0.050*
C10	0.3185 (3)	0.28495 (15)	0.69070 (12)	0.0314 (6)
C11	0.2653 (4)	0.32776 (18)	0.64579 (14)	0.0402 (7)
H11	0.2085	0.3099	0.6131	0.048*
C12	0.2959 (5)	0.39679 (18)	0.64904 (15)	0.0465 (8)
H12	0.2601	0.4252	0.6184	0.056*
C13	0.3804 (4)	0.42454 (18)	0.69822 (14)	0.0419 (8)
C14	0.4350 (4)	0.38054 (17)	0.74268 (15)	0.0423 (8)
H14	0.4939	0.3980	0.7751	0.051*
C15	0.4037 (4)	0.31171 (16)	0.73966 (13)	0.0349 (7)
H15	0.4392	0.2831	0.7702	0.042*
C16	0.4064 (4)	0.49975 (18)	0.70326 (17)	0.0491 (9)
H16A	0.3241	0.5184	0.7304	0.074*
H16B	0.3922	0.5204	0.6650	0.074*
H16C	0.5196	0.5087	0.7177	0.074*
Cl1	0.65350 (9)	0.10276 (4)	0.50665 (3)	0.03580 (19)
N1	0.5083 (4)	0.04372 (13)	0.59707 (12)	0.0407 (6)
N2	0.4620 (3)	0.16217 (13)	0.66251 (11)	0.0334 (6)
H2A	0.547 (4)	0.1794 (17)	0.6841 (15)	0.040*
O1	0.1557 (3)	0.18367 (12)	0.64347 (10)	0.0439 (6)
O2	0.2635 (3)	0.17162 (12)	0.74582 (9)	0.0432 (6)
O3	0.3667 (3)	0.04155 (12)	0.57591 (12)	0.0547 (7)
O4	0.5674 (3)	−0.00057 (13)	0.62846 (12)	0.0595 (7)
S1	0.28433 (9)	0.19677 (4)	0.68662 (3)	0.03081 (19)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0406 (16)	0.0483 (18)	0.0233 (14)	0.0236 (14)	−0.0020 (12)	−0.0033 (14)
C2	0.0365 (16)	0.0373 (16)	0.0261 (14)	0.0020 (13)	0.0056 (12)	−0.0015 (13)
C3	0.0296 (15)	0.0309 (14)	0.0270 (14)	−0.0002 (12)	0.0055 (11)	−0.0002 (12)
C4	0.0267 (14)	0.0322 (15)	0.0290 (15)	−0.0027 (11)	0.0033 (12)	−0.0024 (12)
C5	0.0344 (15)	0.0448 (17)	0.0295 (15)	−0.0005 (14)	−0.0042 (12)	0.0001 (13)
C6	0.056 (2)	0.0446 (19)	0.0242 (16)	0.0022 (15)	0.0026 (14)	0.0134 (14)
C7	0.0534 (19)	0.0383 (18)	0.0393 (19)	−0.0083 (15)	0.0079 (15)	0.0100 (15)
C8	0.0513 (19)	0.0471 (19)	0.0349 (18)	−0.0214 (16)	0.0037 (15)	0.0031 (15)
C9	0.0496 (18)	0.0467 (19)	0.0279 (15)	−0.0154 (15)	−0.0060 (14)	0.0084 (14)
C10	0.0265 (14)	0.0402 (17)	0.0275 (15)	0.0008 (12)	0.0057 (11)	0.0011 (12)
C11	0.0452 (17)	0.0461 (19)	0.0293 (16)	0.0124 (14)	−0.0042 (14)	0.0062 (14)
C12	0.059 (2)	0.0433 (19)	0.0368 (18)	0.0120 (16)	−0.0016 (16)	0.0137 (16)
C13	0.0474 (19)	0.0432 (18)	0.0350 (17)	−0.0008 (14)	0.0099 (14)	0.0068 (15)
C14	0.0435 (18)	0.0471 (19)	0.0363 (17)	−0.0077 (14)	−0.0042 (14)	−0.0025 (15)
C15	0.0373 (15)	0.0392 (16)	0.0281 (15)	−0.0009 (13)	−0.0026 (12)	0.0021 (13)
C16	0.0394 (17)	0.050 (2)	0.058 (2)	−0.0181 (15)	0.0056 (17)	0.0087 (18)
Cl1	0.0403 (4)	0.0396 (4)	0.0275 (4)	0.0017 (3)	0.0128 (3)	−0.0108 (3)
N1	0.0507 (17)	0.0366 (15)	0.0347 (15)	−0.0014 (13)	0.0048 (13)	−0.0007 (12)
N2	0.0326 (13)	0.0325 (14)	0.0351 (15)	0.0000 (10)	0.0028 (11)	−0.0005 (11)
O1	0.0323 (10)	0.0607 (15)	0.0387 (12)	−0.0070 (10)	−0.0006 (10)	−0.0059 (11)
O2	0.0565 (14)	0.0451 (13)	0.0281 (11)	−0.0041 (10)	0.0182 (11)	0.0042 (10)
O3	0.0564 (15)	0.0482 (14)	0.0597 (17)	−0.0259 (12)	0.0007 (13)	−0.0081 (12)
O4	0.0644 (16)	0.0474 (15)	0.0667 (18)	0.0107 (12)	0.0152 (14)	0.0303 (14)
S1	0.0299 (3)	0.0364 (4)	0.0261 (4)	−0.0028 (3)	0.0059 (3)	0.0004 (3)

Geometric parameters (Å, º) top

C1—C2	1.555 (4)	C10—C11	1.379 (4)
C1—H1A	0.9600	C10—C15	1.392 (4)
C1—H1B	0.9600	C10—S1	1.752 (3)
C1—H1C	0.9600	C11—C12	1.377 (5)
C2—C3	1.539 (4)	C11—H11	0.9300
C2—N1	1.544 (4)	C12—C13	1.400 (5)
C2—Cl1	1.761 (3)	C12—H12	0.9300
C3—N2	1.481 (4)	C13—C14	1.390 (5)
C3—C4	1.524 (4)	C13—C16	1.493 (5)
C3—H3	0.9800	C14—C15	1.373 (4)
C4—C9	1.382 (4)	C14—H14	0.9300
C4—C5	1.384 (4)	C15—H15	0.9300
C5—C6	1.380 (4)	C16—H16A	0.9600
C5—H5	0.9300	C16—H16B	0.9600
C6—C7	1.400 (5)	C16—H16C	0.9600
C6—H6	0.9300	N1—O3	1.207 (3)
C7—C8	1.367 (5)	N1—O4	1.212 (3)
C7—H7	0.9300	N2—S1	1.639 (3)
C8—C9	1.395 (4)	N2—H2A	0.89 (3)
C8—H8	0.9300	O1—S1	1.423 (2)
C9—H9	0.9300	O2—S1	1.432 (2)

C2—C1—H1A	109.5	C11—C10—C15	119.8 (3)
C2—C1—H1B	109.5	C11—C10—S1	121.1 (2)
H1A—C1—H1B	109.5	C15—C10—S1	119.1 (2)
C2—C1—H1C	109.5	C12—C11—C10	120.5 (3)
H1A—C1—H1C	109.5	C12—C11—H11	119.8
H1B—C1—H1C	109.5	C10—C11—H11	119.8
C3—C2—N1	105.9 (2)	C11—C12—C13	120.4 (3)
C3—C2—C1	115.5 (2)	C11—C12—H12	119.8
N1—C2—C1	110.5 (2)	C13—C12—H12	119.8
C3—C2—Cl1	110.3 (2)	C14—C13—C12	118.3 (3)
N1—C2—Cl1	103.78 (19)	C14—C13—C16	121.1 (3)
C1—C2—Cl1	110.1 (2)	C12—C13—C16	120.6 (3)
N2—C3—C4	115.3 (2)	C15—C14—C13	121.3 (3)
N2—C3—C2	105.9 (2)	C15—C14—H14	119.3
C4—C3—C2	113.6 (2)	C13—C14—H14	119.3
N2—C3—H3	107.2	C14—C15—C10	119.7 (3)
C4—C3—H3	107.2	C14—C15—H15	120.2
C2—C3—H3	107.2	C10—C15—H15	120.2
C9—C4—C5	119.1 (3)	C13—C16—H16A	109.5
C9—C4—C3	121.5 (3)	C13—C16—H16B	109.5
C5—C4—C3	119.4 (3)	H16A—C16—H16B	109.5
C6—C5—C4	121.4 (3)	C13—C16—H16C	109.5
C6—C5—H5	119.3	H16A—C16—H16C	109.5
C4—C5—H5	119.3	H16B—C16—H16C	109.5
C5—C6—C7	119.0 (3)	O3—N1—O4	123.8 (3)
C5—C6—H6	120.5	O3—N1—C2	117.7 (3)
C7—C6—H6	120.5	O4—N1—C2	118.6 (3)
C8—C7—C6	120.0 (3)	C3—N2—S1	118.6 (2)
C8—C7—H7	120.0	C3—N2—H2A	109 (2)
C6—C7—H7	120.0	S1—N2—H2A	107 (2)
C7—C8—C9	120.5 (3)	O1—S1—O2	119.59 (14)
C7—C8—H8	119.8	O1—S1—N2	107.37 (14)
C9—C8—H8	119.8	O2—S1—N2	105.25 (14)
C4—C9—C8	120.0 (3)	O1—S1—C10	108.79 (14)
C4—C9—H9	120.0	O2—S1—C10	107.97 (14)
C8—C9—H9	120.0	N2—S1—C10	107.24 (13)

N1—C2—C3—N2	59.6 (3)	C12—C13—C14—C15	−1.7 (5)
C1—C2—C3—N2	−63.2 (3)	C16—C13—C14—C15	176.7 (3)
Cl1—C2—C3—N2	171.28 (19)	C13—C14—C15—C10	1.2 (5)
N1—C2—C3—C4	−172.9 (2)	C11—C10—C15—C14	−0.4 (4)
C1—C2—C3—C4	64.4 (3)	S1—C10—C15—C14	178.4 (2)
Cl1—C2—C3—C4	−61.2 (3)	C3—C2—N1—O3	50.9 (3)
N2—C3—C4—C9	36.7 (4)	C1—C2—N1—O3	176.7 (3)
C2—C3—C4—C9	−85.7 (3)	Cl1—C2—N1—O3	−65.3 (3)
N2—C3—C4—C5	−141.2 (3)	C3—C2—N1—O4	−128.4 (3)
C2—C3—C4—C5	96.3 (3)	C1—C2—N1—O4	−2.5 (4)
C9—C4—C5—C6	0.2 (5)	Cl1—C2—N1—O4	115.5 (3)
C3—C4—C5—C6	178.1 (3)	C4—C3—N2—S1	80.2 (3)
C4—C5—C6—C7	−1.6 (5)	C2—C3—N2—S1	−153.3 (2)
C5—C6—C7—C8	2.4 (5)	C3—N2—S1—O1	41.9 (3)
C6—C7—C8—C9	−1.8 (5)	C3—N2—S1—O2	170.3 (2)
C5—C4—C9—C8	0.5 (5)	C3—N2—S1—C10	−74.9 (2)
C3—C4—C9—C8	−177.4 (3)	C11—C10—S1—O1	−18.0 (3)
C7—C8—C9—C4	0.4 (5)	C15—C10—S1—O1	163.2 (2)
C15—C10—C11—C12	0.0 (5)	C11—C10—S1—O2	−149.2 (2)
S1—C10—C11—C12	−178.8 (3)	C15—C10—S1—O2	32.0 (3)
C10—C11—C12—C13	−0.4 (5)	C11—C10—S1—N2	97.8 (3)
C11—C12—C13—C14	1.2 (5)	C15—C10—S1—N2	−80.9 (2)
C11—C12—C13—C16	−177.1 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O1	0.98	2.46	2.933 (4)	109
C3—H3···O3	0.98	2.42	2.779 (4)	101
C1—H1A···O2ⁱ	0.96	2.52	3.369 (4)	147
C1—H1B···O1ⁱⁱ	0.96	2.58	3.310 (4)	133
N2—H2A···O2ⁱ	0.89 (2)	2.32 (3)	3.141 (3)	153

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

Experimental details

Crystal data
Chemical formula	C₁₆H₁₇ClN₂O₄S
M_r	368.83
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	291
a, b, c (Å)	7.8254 (8), 19.610 (2), 22.533 (3)
V (Å³)	3457.8 (7)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.36
Crystal size (mm)	0.30 × 0.26 × 0.24

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2000)
T_min, T_max	0.901, 0.921
No. of measured, independent and observed [I > 2σ(I)] reflections	17527, 3396, 2467
R_int	0.070
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.056, 0.125, 1.01
No. of reflections	3396
No. of parameters	222
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.28, −0.26

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXTL (Bruker, 2000) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O1	0.98	2.46	2.933 (4)	109
C3—H3···O3	0.98	2.42	2.779 (4)	101
C1—H1A···O2ⁱ	0.96	2.52	3.369 (4)	147
C1—H1B···O1ⁱⁱ	0.96	2.58	3.310 (4)	133
N2—H2A···O2ⁱ	0.89 (2)	2.32 (3)	3.141 (3)	153

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

Acknowledgements

This work was supported by the 863 High Technology Program (to YP). The research funds for YP from the Qing-Lan Program of Jiangsu Province and the Kua-Shi-Ji Program of the Education Ministry of China are also acknowledged.

References

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