Ethyl 5-amino-1-(4-chloro-2-nitro­phen­yl)-1H-pyrazole-4-carboxyl­ate

Zia-ur-Rehman, M.; Elsegood, M.R.J.; Choudary, J.A.; Fasih Ullah, M.; Siddiqui, H.L.

doi:10.1107/S1600536809000488

organic compounds

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ISSN: 2056-9890

Volume 65| Part 2| February 2009| Pages o275-o276

doi:10.1107/S1600536809000488

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Ethyl 5-amino-1-(4-chloro-2-nitrophenyl)-1H-pyrazole-4-carboxylate

Muhammad Zia-ur-Rehman,^a ^* Mark R. J. Elsegood,^b Jamil Anwar Choudary,^c Muhammad Fasih Ullah ^c and Hamid Latif Siddiqui ^c

^aApplied Chemistry Research Centre, PCSIR Laboratories Complex, Lahore 54600, Pakistan, ^bChemistry Department, Loughborough University, Loughborough, Leicestershire LE11 3TU, England, and ^cInstitute of Chemistry, University of the Punjab, Lahore 54590, Pakistan
^*Correspondence e-mail: rehman_pcsir@hotmail.com

(Received 20 December 2008; accepted 6 January 2009; online 10 January 2009)

In the molecule of the title compound, C₁₂H₁₁ClN₄O₄, the pyrazole ring is coplanar with the amino and ethoxycarbonyl groups within 0.026 (2) and 0.105 (2) Å, respectively. The C₆ ring of the 4-chloro-2-nitrophenyl group is twisted by 53.58 (4)° relative to the plane of the pyrazole ring. The planar structure of the pyrazole ring is stabilized by an intramolecular N—H⋯O hydrogen bond between its substituents. Neighbouring molecules are linked through intermolecular N—H⋯N and N—H⋯O hydrogen bonds, giving rise to one-dimensional tapes along the b axis. Molecules in the chain are linked to those of an adjacent chain through weak C—H⋯O interactions, forming a three-dimensional network.

Related literature

For the biological activity of pyrazole and its derivatives, see: Iovu et al. (2003 ); Mahajan et al. (1991 ); related literature, see: Akhtar et al. (2008 ); Baraldi et al. (1998 ); Bruno et al. (1990 ); Cottineau et al. (2002 ); Smith et al. (2001 ). For the use of pyrazole-based ligands in investigating the structure–activity relationship of the active site of metalloproteins, see: Dardari et al. (2006 ), and in the preparation of commercially important dyestuffs, see: Baroni & Kovyrzina (1961 ); Neunhoeffer et al. (1959 ). For the synthesis and biological evaluation of heterocyclic compounds, see: Akhtar et al. (2008); Zia-ur-Rehman et al. (2006 , 2008 ).

Experimental

Crystal data

C₁₂H₁₁ClN₄O₄
M_r = 310.70
Monoclinic, P 2₁ /n
a = 8.5899 (8) Å
b = 10.2413 (9) Å
c = 15.6633 (14) Å
β = 96.5415 (13)°
V = 1369.0 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.30 mm⁻¹
T = 150 (2) K
0.79 × 0.27 × 0.09 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2007 ) T_min = 0.797, T_max = 0.973
15944 measured reflections
4189 independent reflections
3588 reflections with I > 2σ(I)
R_int = 0.022

Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.096
S = 1.04
4189 reflections
197 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.44 e Å⁻³
Δρ_min = −0.27 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N4—H4A⋯O3	0.866 (16)	2.328 (16)	2.9383 (13)	127.7 (12)
N4—H4A⋯O2ⁱ	0.866 (16)	2.610 (15)	3.1356 (13)	120.1 (12)
N4—H4B⋯N3ⁱ	0.871 (15)	2.153 (16)	3.0074 (13)	166.8 (14)
Symmetry code: (i) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Data collection: APEX2 (Bruker, 2006 ); cell refinement: SAINT (Bruker, 2006); 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 and local programs.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809000488/bt2841sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809000488/bt2841Isup2.hkl

checkCIF report

Comment top

Pyrazole and its derivatives represent one of the most important classes of organic heterocyclic compounds, possessing a wide spectrum of biological activities such as antibacterial, fungicidal (Iovu et al., 2003), herbicidal (Mahajan et al.,1991) and antiviral (Baraldi et al., 1998) activities. Some of their derivatives have been reported to possess significant antiarrhythmic & sedative (Bruno et al., 1990), hypoglycemic (Cottineau et al., 2002) and anti-inflammatory (Smith et al., 2001) activities. In addition, pyrazole based ligands have also been used to investigate the structure-activity relationship of the active site of metalloproteins (Dardari et al., 2006) and for the preparation of commercially important dyestuffs (Baroni & Kovyrzina, 1961; Neunhoeffer et al.,1959). As part of our ongoing research on the synthesis and biological evaluation of heterocyclic compounds (Akhtar et al., 2008; Zia-ur-Rehman et al., 2006; Zia-ur-Rehman et al., 2008), crystal structure of the title compound, (I) was determined.

In I (Fig. 1) the pyrazole ring is approximately coplanar with the amino and ethyl carboxylate groups. The C₆ ring of the 4-chloro-2-nitro phenyl group is essentially planar and is twisted by 53.58 (4)° relative to the plane of the pyrazole ring about the C6—N2 bond. The planar structure of the pyrazole ring is stabilized by an intramolecular N—H···O hydrogen bond between the amino and ethyl carboxylate substituents (Table 1). Neighbouring molecules are linked through one N—H···N and one N—H···O intermolecular hydrogen bond giving rise to one-dimensional tapes along the b axis (Fig. 2, Table 1). The nitro group is twisted by 37.98 (4)° relative to the C₆ ring, driven by the desire to form the aforementioned H-bond. Each chain is cross-linked to the next through weak C–H···O interactions.

Related literature top

For the biological activity of pyrazole and its derivatives, see: Iovu et al. (2003); Mahajan et al. (1991); related literature, see: Akhtar et al. (2008); Baraldi et al. (1998); Bruno et al. (1990); Cottineau et al. (2002); Smith et al. (2001). For the use of pyrazole-based ligands in investigating the structure–activity relationship of the active site of metalloproteins, see: Dardari et al., 2006), and in the preparation of commercially important dyestuffs, see: Baroni & Kovyrzina (1961); Neunhoeffer et al. (1959). For the synthesis and biological evaluation of heterocyclic compounds, see: Akhtar et al. (2008); Zia-ur-Rehman et al. (2006, 2008).

Experimental top

A mixture of 5-amino-1-(4-chloro-2-nitrophenyl)-1H-pyrazole-4-carboxylic acid (3.05 g; 10.0 mmoles), phosphoric acid (0.196 g; 2.0 mmoles) and ethyl alcohol (100 ml) was refluxed for a period of five hours. The reaction mixture was then concentrated (to a volume of 20 ml) by slow distillation of ethanol followed by cooling and addition of cold water. The precipitated solid was then filtered, washed with cold water and dried. Crystals suitable for single-crystal X-ray diffraction were grown by slow evaporation of a solution of the title compound in a mixture of ethanol and water (85: 15); yield: 73.68%.

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 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: SHELXTL (Sheldrick, 2008) and local programs.

Figures top

	Fig. 1. The asymmetric unit of the title compound highlighting the intramolecular H-bond. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Perspective view of the crystal packing showing hydrogen-bond interactions (dashed lines). H atoms not involved in hydrogen bonding have been omitted for clarity. Symmetry operator i = -x + 1/2, y - 1/2, -z + 3/2.

Ethyl 1-(4-chloro-2-nitrophenyl)-5-nitro-4, 5-dihydro-1H-pyrazole-4-carboxylate top

Crystal data top

C₁₂H₁₁ClN₄O₄	F(000) = 640
M_r = 310.70	D_x = 1.508 Mg m⁻³
Monoclinic, P2₁/n	Melting point: 435 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 8.5899 (8) Å	Cell parameters from 6502 reflections
b = 10.2413 (9) Å	θ = 2.6–30.6°
c = 15.6633 (14) Å	µ = 0.30 mm⁻¹
β = 96.5415 (13)°	T = 150 K
V = 1369.0 (2) Å³	Lath, colourless
Z = 4	0.79 × 0.27 × 0.09 mm

Data collection top

Bruker APEXII CCD diffractometer	4189 independent reflections
Radiation source: fine-focus sealed tube	3588 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.022
ω rotation with narrow frames scans	θ_max = 30.6°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 2007)	h = −12→12
T_min = 0.797, T_max = 0.973	k = −14→14
15944 measured reflections	l = −22→22

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: all non-H atoms found by direct methods
R[F² > 2σ(F²)] = 0.034	Hydrogen site location: geom except NH coords freely refined
wR(F²) = 0.096	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ²(F_o²) + (0.0507P)² + 0.3692P] where P = (F_o² + 2F_c²)/3
4189 reflections	(Δ/σ)_max = 0.001
197 parameters	Δρ_max = 0.44 e Å⁻³
0 restraints	Δρ_min = −0.27 e Å⁻³

Crystal data top

C₁₂H₁₁ClN₄O₄	V = 1369.0 (2) Å³
M_r = 310.70	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 8.5899 (8) Å	µ = 0.30 mm⁻¹
b = 10.2413 (9) Å	T = 150 K
c = 15.6633 (14) Å	0.79 × 0.27 × 0.09 mm
β = 96.5415 (13)°

Data collection top

Bruker APEXII CCD diffractometer	4189 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2007)	3588 reflections with I > 2σ(I)
T_min = 0.797, T_max = 0.973	R_int = 0.022
15944 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	0 restraints
wR(F²) = 0.096	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	Δρ_max = 0.44 e Å⁻³
4189 reflections	Δρ_min = −0.27 e Å⁻³
197 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	0.16661 (12)	0.37722 (10)	0.87165 (6)	0.01863 (19)
N1	0.00154 (11)	0.39144 (9)	0.83571 (6)	0.02209 (18)
O1	−0.04727 (11)	0.32020 (9)	0.77617 (6)	0.0316 (2)
O2	−0.07682 (10)	0.47313 (9)	0.86871 (6)	0.03110 (19)
C2	0.19621 (13)	0.36020 (11)	0.95971 (7)	0.0216 (2)
H2	0.1135	0.3609	0.9951	0.026*
C3	0.35046 (14)	0.34216 (10)	0.99458 (7)	0.0224 (2)
Cl1	0.39123 (4)	0.31052 (3)	1.103127 (17)	0.03302 (9)
C4	0.47238 (13)	0.34677 (11)	0.94341 (7)	0.0229 (2)
H4	0.5777	0.3370	0.9685	0.028*
C5	0.43941 (13)	0.36565 (10)	0.85546 (7)	0.0218 (2)
H5	0.5227	0.3691	0.8205	0.026*
C6	0.28554 (12)	0.37949 (10)	0.81810 (6)	0.01836 (19)
N2	0.25381 (11)	0.40263 (9)	0.72882 (5)	0.01940 (17)
N3	0.16947 (11)	0.51311 (9)	0.69958 (6)	0.02197 (19)
C7	0.17042 (12)	0.51027 (10)	0.61560 (7)	0.0206 (2)
H7	0.1215	0.5744	0.5778	0.025*
C8	0.25215 (12)	0.40156 (10)	0.58811 (6)	0.01772 (19)
C9	0.30396 (12)	0.33322 (10)	0.66310 (6)	0.01755 (19)
N4	0.39081 (12)	0.22356 (9)	0.67437 (6)	0.0241 (2)
H4A	0.4077 (18)	0.1853 (14)	0.6270 (11)	0.029*
H4B	0.3806 (18)	0.1713 (14)	0.7173 (10)	0.029*
C10	0.28074 (12)	0.36124 (10)	0.50279 (6)	0.01900 (19)
O3	0.35936 (10)	0.26670 (8)	0.48774 (5)	0.02577 (17)
O4	0.20696 (9)	0.43861 (8)	0.44194 (5)	0.02405 (17)
C11	0.23017 (13)	0.40996 (12)	0.35329 (7)	0.0250 (2)
H11A	0.1377	0.4396	0.3146	0.030*
H11B	0.2407	0.3145	0.3460	0.030*
C12	0.37412 (17)	0.47691 (14)	0.32935 (9)	0.0355 (3)
H12A	0.3655	0.5711	0.3389	0.053*
H12B	0.3845	0.4605	0.2686	0.053*
H12C	0.4665	0.4429	0.3649	0.053*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0220 (5)	0.0179 (4)	0.0160 (4)	0.0002 (4)	0.0023 (4)	−0.0002 (3)
N1	0.0232 (4)	0.0248 (4)	0.0183 (4)	−0.0023 (3)	0.0024 (3)	0.0032 (3)
O1	0.0339 (5)	0.0367 (5)	0.0230 (4)	−0.0084 (4)	−0.0021 (3)	−0.0042 (3)
O2	0.0271 (4)	0.0339 (5)	0.0330 (5)	0.0062 (3)	0.0063 (3)	−0.0003 (4)
C2	0.0273 (5)	0.0227 (5)	0.0153 (4)	−0.0007 (4)	0.0047 (4)	−0.0004 (4)
C3	0.0319 (5)	0.0202 (5)	0.0146 (4)	0.0005 (4)	0.0007 (4)	−0.0002 (4)
Cl1	0.04426 (18)	0.03893 (17)	0.01462 (13)	0.00482 (13)	−0.00204 (11)	0.00275 (10)
C4	0.0253 (5)	0.0213 (5)	0.0213 (5)	0.0024 (4)	−0.0011 (4)	0.0009 (4)
C5	0.0243 (5)	0.0208 (5)	0.0209 (5)	0.0029 (4)	0.0054 (4)	0.0020 (4)
C6	0.0256 (5)	0.0164 (4)	0.0134 (4)	0.0016 (4)	0.0035 (4)	0.0008 (3)
N2	0.0258 (4)	0.0188 (4)	0.0142 (4)	0.0057 (3)	0.0046 (3)	0.0019 (3)
N3	0.0291 (4)	0.0192 (4)	0.0179 (4)	0.0085 (3)	0.0044 (3)	0.0019 (3)
C7	0.0237 (5)	0.0207 (5)	0.0174 (4)	0.0043 (4)	0.0030 (4)	0.0022 (4)
C8	0.0202 (4)	0.0185 (4)	0.0149 (4)	0.0013 (3)	0.0038 (3)	0.0015 (3)
C9	0.0205 (4)	0.0171 (4)	0.0156 (4)	0.0007 (3)	0.0048 (3)	0.0004 (3)
N4	0.0361 (5)	0.0188 (4)	0.0187 (4)	0.0091 (4)	0.0090 (4)	0.0037 (3)
C10	0.0193 (4)	0.0223 (5)	0.0157 (4)	−0.0012 (4)	0.0028 (3)	0.0010 (4)
O3	0.0318 (4)	0.0266 (4)	0.0196 (4)	0.0076 (3)	0.0058 (3)	−0.0015 (3)
O4	0.0266 (4)	0.0313 (4)	0.0145 (3)	0.0064 (3)	0.0031 (3)	0.0029 (3)
C11	0.0238 (5)	0.0369 (6)	0.0141 (4)	−0.0005 (4)	0.0019 (4)	0.0012 (4)
C12	0.0395 (7)	0.0374 (7)	0.0321 (6)	−0.0095 (6)	0.0150 (5)	0.0001 (5)

Geometric parameters (Å, º) top

C1—C2	1.3848 (14)	C7—C8	1.4096 (14)
C1—C6	1.3940 (14)	C7—H7	0.9500
C1—N1	1.4719 (14)	C8—C9	1.3958 (14)
N1—O1	1.2202 (13)	C8—C10	1.4462 (14)
N1—O2	1.2245 (13)	C9—N4	1.3487 (13)
C2—C3	1.3868 (16)	N4—H4A	0.866 (16)
C2—H2	0.9500	N4—H4B	0.871 (15)
C3—C4	1.3902 (16)	C10—O3	1.2188 (13)
C3—Cl1	1.7271 (11)	C10—O4	1.3418 (12)
C4—C5	1.3881 (15)	O4—C11	1.4549 (13)
C4—H4	0.9500	C11—C12	1.4985 (17)
C5—C6	1.3904 (15)	C11—H11A	0.9900
C5—H5	0.9500	C11—H11B	0.9900
C6—N2	1.4140 (12)	C12—H12A	0.9800
N2—C9	1.3607 (13)	C12—H12B	0.9800
N2—N3	1.3925 (12)	C12—H12C	0.9800
N3—C7	1.3166 (13)

C2—C1—C6	122.51 (10)	C8—C7—H7	123.8
C2—C1—N1	116.93 (9)	C9—C8—C7	105.13 (9)
C6—C1—N1	120.55 (9)	C9—C8—C10	124.27 (9)
O1—N1—O2	125.00 (10)	C7—C8—C10	130.60 (9)
O1—N1—C1	117.73 (9)	N4—C9—N2	123.64 (9)
O2—N1—C1	117.26 (9)	N4—C9—C8	130.26 (9)
C1—C2—C3	117.89 (10)	N2—C9—C8	106.06 (9)
C1—C2—H2	121.1	C9—N4—H4A	114.1 (10)
C3—C2—H2	121.1	C9—N4—H4B	120.7 (10)
C2—C3—C4	121.15 (10)	H4A—N4—H4B	115.1 (14)
C2—C3—Cl1	119.35 (9)	O3—C10—O4	123.99 (9)
C4—C3—Cl1	119.49 (9)	O3—C10—C8	124.18 (9)
C5—C4—C3	119.67 (10)	O4—C10—C8	111.82 (9)
C5—C4—H4	120.2	C10—O4—C11	116.99 (9)
C3—C4—H4	120.2	O4—C11—C12	110.69 (10)
C4—C5—C6	120.57 (10)	O4—C11—H11A	109.5
C4—C5—H5	119.7	C12—C11—H11A	109.5
C6—C5—H5	119.7	O4—C11—H11B	109.5
C5—C6—C1	118.15 (9)	C12—C11—H11B	109.5
C5—C6—N2	120.01 (9)	H11A—C11—H11B	108.1
C1—C6—N2	121.74 (9)	C11—C12—H12A	109.5
C9—N2—N3	111.92 (8)	C11—C12—H12B	109.5
C9—N2—C6	128.23 (9)	H12A—C12—H12B	109.5
N3—N2—C6	119.72 (8)	C11—C12—H12C	109.5
C7—N3—N2	104.38 (8)	H12A—C12—H12C	109.5
N3—C7—C8	112.50 (9)	H12B—C12—H12C	109.5
N3—C7—H7	123.8

C2—C1—N1—O1	−127.78 (11)	C9—N2—N3—C7	−0.53 (12)
C6—C1—N1—O1	51.47 (14)	C6—N2—N3—C7	175.66 (9)
C2—C1—N1—O2	51.39 (13)	N2—N3—C7—C8	0.14 (12)
C6—C1—N1—O2	−129.37 (11)	N3—C7—C8—C9	0.27 (12)
C6—C1—C2—C3	−1.37 (16)	N3—C7—C8—C10	179.76 (10)
N1—C1—C2—C3	177.85 (9)	N3—N2—C9—N4	178.62 (10)
C1—C2—C3—C4	2.81 (16)	C6—N2—C9—N4	2.83 (17)
C1—C2—C3—Cl1	−176.02 (8)	N3—N2—C9—C8	0.70 (12)
C2—C3—C4—C5	−2.04 (17)	C6—N2—C9—C8	−175.09 (10)
Cl1—C3—C4—C5	176.78 (8)	C7—C8—C9—N4	−178.30 (11)
C3—C4—C5—C6	−0.24 (16)	C10—C8—C9—N4	2.17 (18)
C4—C5—C6—C1	1.62 (16)	C7—C8—C9—N2	−0.57 (11)
C4—C5—C6—N2	178.08 (10)	C10—C8—C9—N2	179.90 (10)
C2—C1—C6—C5	−0.81 (16)	C9—C8—C10—O3	−3.61 (17)
N1—C1—C6—C5	179.99 (9)	C7—C8—C10—O3	176.99 (11)
C2—C1—C6—N2	−177.21 (10)	C9—C8—C10—O4	174.82 (10)
N1—C1—C6—N2	3.59 (15)	C7—C8—C10—O4	−4.59 (16)
C5—C6—N2—C9	52.72 (15)	O3—C10—O4—C11	−3.17 (15)
C1—C6—N2—C9	−130.95 (11)	C8—C10—O4—C11	178.40 (9)
C5—C6—N2—N3	−122.79 (11)	C10—O4—C11—C12	−86.64 (13)
C1—C6—N2—N3	53.54 (14)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N4—H4A···O3	0.866 (16)	2.328 (16)	2.9383 (13)	127.7 (12)
N4—H4A···O2ⁱ	0.866 (16)	2.610 (15)	3.1356 (13)	120.1 (12)
N4—H4B···N3ⁱ	0.871 (15)	2.153 (16)	3.0074 (13)	166.8 (14)

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

Experimental details

Crystal data
Chemical formula	C₁₂H₁₁ClN₄O₄
M_r	310.70
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	150
a, b, c (Å)	8.5899 (8), 10.2413 (9), 15.6633 (14)
β (°)	96.5415 (13)
V (Å³)	1369.0 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.30
Crystal size (mm)	0.79 × 0.27 × 0.09

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2007)
T_min, T_max	0.797, 0.973
No. of measured, independent and observed [I > 2σ(I)] reflections	15944, 4189, 3588
R_int	0.022
(sin θ/λ)_max (Å⁻¹)	0.715

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.034, 0.096, 1.04
No. of reflections	4189
No. of parameters	197
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.44, −0.27

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and local programs.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N4—H4A···O3	0.866 (16)	2.328 (16)	2.9383 (13)	127.7 (12)
N4—H4A···O2ⁱ	0.866 (16)	2.610 (15)	3.1356 (13)	120.1 (12)
N4—H4B···N3ⁱ	0.871 (15)	2.153 (16)	3.0074 (13)	166.8 (14)

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

Acknowledgements

The authors are grateful to the Pakistan Council of Scientific & Industrial Research Laboratories, Lahore, Pakistan, for the provision of necessary chemicals.

References

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