organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

Ethyl 5-amino-1-(6-chloro­pyridazin-3-yl)-1H-pyrazole-4-carboxyl­ate

aDepartment of Chemistry, Islamia University, Bahawalpur, Pakistan, bApplied Chemistry Research Center, PCSIR Laboratories Complex, Lahore 54600, Pakistan, cDepartment of Physics, University of Sargodha, Sargodha, Pakistan, dInstitute of Chemistry, University of the Punjab, Lahore, Pakistan, and eInstituto de Quimica, Universidade Estadual de Londrina, Londrina, Pr., Brazil
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 23 August 2010; accepted 25 August 2010; online 28 August 2010)

In the title compound, C10H10ClN5O2, the dihedral angle between the aromatic rings is 0.16 (9)°. Two S(6) ring motifs are formed due to intra­molecular N—H⋯N and N—H⋯O hydrogen bonds. In the crystal, inversion dimers linked by pairs of N—H⋯N hydrogen bonds generate R22(14) [or R44(10) via the intra­molecular hydrogen bonds] ring motifs. Polymeric chains propagating in [210] are formed as a result of inter­linking the dimers by pairs of C—H⋯N inter­actions, completing R22(6) ring motifs.

Related literature

For biochemical background and related structures, see: Ather et al. (2010a[Ather, A. Q., Tahir, M. N., Khan, M. A. & Athar, M. M. (2010a). Acta Cryst. E66, o1327.],b[Ather, A. Q., Tahir, M. N., Khan, M. A., Athar, M. M. & Bueno, E. A. S. (2010b). Acta Cryst. E66, o1900.],c[Ather, A. Q., Tahir, M. N., Khan, M. A., Athar, M. M. & Bueno, E. A. S. (2010c). Acta Cryst. E66, o2016.]). For graph-set notation, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C10H10ClN5O2

  • Mr = 267.68

  • Triclinic, [P \overline 1]

  • a = 5.3618 (3) Å

  • b = 8.6168 (4) Å

  • c = 13.1585 (7) Å

  • α = 77.734 (2)°

  • β = 82.928 (1)°

  • γ = 86.722 (2)°

  • V = 589.24 (5) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.33 mm−1

  • T = 296 K

  • 0.25 × 0.20 × 0.08 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.982, Tmax = 0.988

  • 8832 measured reflections

  • 2125 independent reflections

  • 1721 reflections with I > 2σ(I)

  • Rint = 0.032

Refinement
  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.101

  • S = 1.06

  • 2125 reflections

  • 164 parameters

  • H-atom parameters constrained

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.16 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N5—H5A⋯N1 0.86 2.17 2.775 (2) 127
N5—H5B⋯O2 0.86 2.40 2.942 (2) 122
N5—H5B⋯N2i 0.86 2.41 3.017 (2) 128
C5—H5⋯N4ii 0.93 2.53 3.313 (2) 142
Symmetry codes: (i) -x+2, -y+1, -z; (ii) -x, -y+2, -z.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information


Comment top

In continuation of our studies of pyrazolylpyridazine derivatives (Ather et al., 2010a, b, c), the title compound (I, Fig. 1) is being reported here.

In (I), the 1-(6-chloropyridazin-3-yl)-1H-pyrazol-5-amine moiety A (C1—C7/N1—N5/CL1) and ethyl formate group B (C8—C10/O1/O2) are planar with r. m. s. deviations of 0.0026 and 0.0293 Å, respectively. The dihedral angle between A/B is 3.09 (12)°. There exist two S(6) ring motifs (Bernstein et al., 1995) due to N–H···N and N—H···O types of intramolecular H-bondings (Table 1, Fig. 1). The molecules are dimerized due to N–H···N type of H-bonding (Table 2, Fig. 2) with R44(10) ring motifs. The dimers are interliked in the from of polymeric chains due to H-bondings of C—H···N type with R22(6) ring motifs (Table 2, Fig. 2).

Related literature top

For biochemical background and related structures, see: Ather et al. (2010a,b,c). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

3-Chloro-6-hydrazinylpyridazine (2 g, 13.84 mmol) and ethylethoxymethylene cyanoacetate (2.35 g, 13.84 mmol) were dissolved in acetic acid (10 ml). The obtained reaction mixture was refluxed for 4 h and cooled to room temperature. The resulting product was poured in 100 ml of distiled water and the precipitates were formed. The precipitates obtained by filteration were washed three times by water. The crude material obtained was dried and purified by column chromatography. The final product was re-crystallized in benzene to obtain light brown plates of (I).

Refinement top

The H-atoms were positioned geometrically (N–H = 0.86, C–H = 0.93–0.97 Å) and were included in the refinement in the riding model approximation, with Uiso(H) = xUeq(C, N), where x = 1.5 for methyl and x = 1.2 for all other H-atoms.

Structure description top

In continuation of our studies of pyrazolylpyridazine derivatives (Ather et al., 2010a, b, c), the title compound (I, Fig. 1) is being reported here.

In (I), the 1-(6-chloropyridazin-3-yl)-1H-pyrazol-5-amine moiety A (C1—C7/N1—N5/CL1) and ethyl formate group B (C8—C10/O1/O2) are planar with r. m. s. deviations of 0.0026 and 0.0293 Å, respectively. The dihedral angle between A/B is 3.09 (12)°. There exist two S(6) ring motifs (Bernstein et al., 1995) due to N–H···N and N—H···O types of intramolecular H-bondings (Table 1, Fig. 1). The molecules are dimerized due to N–H···N type of H-bonding (Table 2, Fig. 2) with R44(10) ring motifs. The dimers are interliked in the from of polymeric chains due to H-bondings of C—H···N type with R22(6) ring motifs (Table 2, Fig. 2).

For biochemical background and related structures, see: Ather et al. (2010a,b,c). For graph-set notation, see: Bernstein et al. (1995).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. View of (I) with displacement ellipsoids drawn at the 50% probability level. H-atoms are shown as small spheres of arbitrary radius. The dotted lines indicate the intramolecular H-bonds.
[Figure 2] Fig. 2. Packing diagram of (I) showing that the molecules form dimers, which are interlinked in the form of polymeric chains.
Ethyl 5-amino-1-(6-chloropyridazin-3-yl)-1H-pyrazole-4-carboxylate top
Crystal data top
C10H10ClN5O2Z = 2
Mr = 267.68F(000) = 276
Triclinic, P1Dx = 1.509 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 5.3618 (3) ÅCell parameters from 1721 reflections
b = 8.6168 (4) Åθ = 2.4–25.2°
c = 13.1585 (7) ŵ = 0.33 mm1
α = 77.734 (2)°T = 296 K
β = 82.928 (1)°Plate, light brown
γ = 86.722 (2)°0.25 × 0.20 × 0.08 mm
V = 589.24 (5) Å3
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2125 independent reflections
Radiation source: fine-focus sealed tube1721 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.032
Detector resolution: 8.10 pixels mm-1θmax = 25.2°, θmin = 2.4°
ω scansh = 66
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
k = 1010
Tmin = 0.982, Tmax = 0.988l = 1515
8832 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.101H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.049P)2 + 0.1261P]
where P = (Fo2 + 2Fc2)/3
2125 reflections(Δ/σ)max = 0.001
164 parametersΔρmax = 0.22 e Å3
0 restraintsΔρmin = 0.16 e Å3
Crystal data top
C10H10ClN5O2γ = 86.722 (2)°
Mr = 267.68V = 589.24 (5) Å3
Triclinic, P1Z = 2
a = 5.3618 (3) ÅMo Kα radiation
b = 8.6168 (4) ŵ = 0.33 mm1
c = 13.1585 (7) ÅT = 296 K
α = 77.734 (2)°0.25 × 0.20 × 0.08 mm
β = 82.928 (1)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2125 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
1721 reflections with I > 2σ(I)
Tmin = 0.982, Tmax = 0.988Rint = 0.032
8832 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.101H-atom parameters constrained
S = 1.06Δρmax = 0.22 e Å3
2125 reflectionsΔρmin = 0.16 e Å3
164 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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
xyzUiso*/Ueq
Cl11.21255 (10)0.81971 (7)0.39777 (4)0.0677 (2)
O10.0151 (3)0.69934 (15)0.27701 (10)0.0604 (4)
O20.3413 (3)0.52161 (16)0.27988 (10)0.0640 (5)
N10.8615 (3)0.69752 (18)0.12132 (12)0.0510 (5)
N21.0286 (3)0.70752 (18)0.20741 (12)0.0542 (5)
N30.4983 (2)0.78156 (16)0.03130 (10)0.0431 (5)
N40.2872 (3)0.88448 (17)0.03037 (12)0.0502 (5)
N50.6846 (3)0.56546 (17)0.08430 (12)0.0555 (5)
C10.6639 (3)0.79680 (19)0.12305 (13)0.0415 (5)
C20.6174 (3)0.9141 (2)0.21063 (15)0.0533 (6)
C30.7854 (3)0.9223 (2)0.29680 (15)0.0561 (6)
C40.9885 (3)0.8155 (2)0.29040 (14)0.0481 (6)
C50.1714 (3)0.8415 (2)0.06357 (14)0.0500 (6)
C60.2931 (3)0.7149 (2)0.12671 (13)0.0445 (5)
C70.5052 (3)0.67718 (19)0.06360 (13)0.0422 (5)
C80.2250 (3)0.6341 (2)0.23350 (14)0.0486 (6)
C90.0707 (5)0.6236 (3)0.38284 (17)0.0732 (8)
C100.2913 (4)0.7155 (3)0.42191 (19)0.0806 (9)
H20.477680.983100.209530.0639*
H30.765390.996750.357970.0673*
H50.022100.890120.086730.0600*
H5A0.806220.555120.036860.0665*
H5B0.678870.503660.145120.0665*
H9A0.063060.619350.426850.0879*
H9B0.117310.515680.385140.0879*
H10A0.422480.719870.377780.1208*
H10B0.242950.821390.420990.1208*
H10C0.351080.664600.492220.1208*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0694 (3)0.0765 (4)0.0499 (3)0.0052 (3)0.0126 (2)0.0098 (3)
O10.0675 (8)0.0591 (8)0.0434 (7)0.0132 (6)0.0109 (6)0.0005 (6)
O20.0691 (9)0.0651 (9)0.0483 (8)0.0172 (7)0.0037 (7)0.0029 (6)
N10.0510 (8)0.0536 (9)0.0424 (8)0.0121 (7)0.0004 (7)0.0037 (7)
N20.0530 (9)0.0583 (10)0.0457 (9)0.0122 (7)0.0024 (7)0.0064 (8)
N30.0442 (8)0.0407 (8)0.0398 (8)0.0096 (6)0.0023 (6)0.0027 (6)
N40.0469 (8)0.0485 (8)0.0486 (9)0.0168 (7)0.0014 (7)0.0022 (7)
N50.0544 (9)0.0579 (10)0.0445 (9)0.0196 (7)0.0021 (7)0.0032 (7)
C10.0422 (9)0.0420 (9)0.0395 (9)0.0041 (7)0.0040 (7)0.0085 (7)
C20.0535 (10)0.0515 (10)0.0480 (11)0.0137 (8)0.0039 (8)0.0003 (8)
C30.0608 (11)0.0570 (11)0.0428 (10)0.0081 (9)0.0026 (9)0.0026 (9)
C40.0512 (10)0.0512 (10)0.0403 (10)0.0011 (8)0.0008 (8)0.0093 (8)
C50.0472 (9)0.0500 (10)0.0479 (10)0.0106 (8)0.0013 (8)0.0064 (8)
C60.0462 (9)0.0451 (9)0.0390 (9)0.0058 (7)0.0027 (7)0.0050 (8)
C70.0441 (9)0.0404 (9)0.0400 (9)0.0047 (7)0.0058 (7)0.0050 (7)
C80.0526 (10)0.0482 (10)0.0429 (10)0.0042 (8)0.0034 (8)0.0073 (8)
C90.0894 (15)0.0670 (13)0.0492 (12)0.0089 (11)0.0189 (11)0.0010 (10)
C100.0777 (15)0.0906 (17)0.0658 (15)0.0008 (13)0.0197 (12)0.0161 (13)
Geometric parameters (Å, º) top
Cl1—C41.7337 (18)C2—C31.351 (3)
O1—C81.348 (2)C3—C41.384 (2)
O1—C91.438 (3)C5—C61.405 (2)
O2—C81.214 (2)C6—C71.389 (2)
N1—N21.346 (2)C6—C81.442 (2)
N1—C11.323 (2)C9—C101.486 (4)
N2—C41.307 (2)C2—H20.9300
N3—N41.398 (2)C3—H30.9300
N3—C11.395 (2)C5—H50.9300
N3—C71.378 (2)C9—H9A0.9700
N4—C51.301 (2)C9—H9B0.9700
N5—C71.332 (2)C10—H10A0.9600
N5—H5A0.8600C10—H10B0.9600
N5—H5B0.8600C10—H10C0.9600
C1—C21.400 (2)
C8—O1—C9115.59 (16)N3—C7—N5124.20 (15)
N2—N1—C1119.35 (15)N3—C7—C6105.71 (14)
N1—N2—C4118.42 (16)O1—C8—O2123.39 (16)
N4—N3—C1118.30 (13)O1—C8—C6111.74 (15)
N4—N3—C7111.47 (12)O2—C8—C6124.87 (16)
C1—N3—C7130.23 (13)O1—C9—C10109.1 (2)
N3—N4—C5104.02 (14)C1—C2—H2122.00
H5A—N5—H5B120.00C3—C2—H2122.00
C7—N5—H5A120.00C2—C3—H3121.00
C7—N5—H5B120.00C4—C3—H3121.00
N1—C1—N3116.76 (15)N4—C5—H5123.00
N1—C1—C2123.38 (16)C6—C5—H5123.00
N3—C1—C2119.86 (15)O1—C9—H9A110.00
C1—C2—C3116.75 (16)O1—C9—H9B110.00
C2—C3—C4117.32 (17)C10—C9—H9A110.00
N2—C4—C3124.78 (17)C10—C9—H9B110.00
Cl1—C4—C3119.87 (14)H9A—C9—H9B108.00
Cl1—C4—N2115.35 (13)C9—C10—H10A109.00
N4—C5—C6113.70 (15)C9—C10—H10B109.00
C5—C6—C7105.11 (15)C9—C10—H10C109.00
C5—C6—C8130.39 (16)H10A—C10—H10B109.00
C7—C6—C8124.51 (15)H10A—C10—H10C109.00
N5—C7—C6130.09 (16)H10B—C10—H10C109.00
C9—O1—C8—O22.0 (3)C1—N3—C7—C6179.82 (16)
C9—O1—C8—C6178.45 (17)N3—N4—C5—C60.2 (2)
C8—O1—C9—C10176.03 (17)N1—C1—C2—C30.6 (3)
C1—N1—N2—C40.3 (2)N3—C1—C2—C3179.95 (16)
N2—N1—C1—N3179.52 (15)C1—C2—C3—C40.6 (2)
N2—N1—C1—C20.1 (3)C2—C3—C4—Cl1179.69 (14)
N1—N2—C4—Cl1179.85 (13)C2—C3—C4—N20.2 (3)
N1—N2—C4—C30.2 (3)N4—C5—C6—C70.2 (2)
C1—N3—N4—C5179.72 (14)N4—C5—C6—C8179.72 (17)
C7—N3—N4—C50.00 (18)C5—C6—C7—N30.21 (18)
N4—N3—C1—N1179.93 (15)C5—C6—C7—N5179.42 (18)
N4—N3—C1—C20.6 (2)C8—C6—C7—N3179.73 (16)
C7—N3—C1—N10.3 (3)C8—C6—C7—N50.1 (3)
C7—N3—C1—C2179.69 (16)C5—C6—C8—O12.9 (3)
N4—N3—C7—N5179.53 (15)C5—C6—C8—O2177.57 (18)
N4—N3—C7—C60.13 (18)C7—C6—C8—O1177.73 (16)
C1—N3—C7—N50.2 (3)C7—C6—C8—O21.8 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N5—H5A···N10.862.172.775 (2)127
N5—H5B···O20.862.402.942 (2)122
N5—H5B···N2i0.862.413.017 (2)128
C5—H5···N4ii0.932.533.313 (2)142
Symmetry codes: (i) x+2, y+1, z; (ii) x, y+2, z.

Experimental details

Crystal data
Chemical formulaC10H10ClN5O2
Mr267.68
Crystal system, space groupTriclinic, P1
Temperature (K)296
a, b, c (Å)5.3618 (3), 8.6168 (4), 13.1585 (7)
α, β, γ (°)77.734 (2), 82.928 (1), 86.722 (2)
V3)589.24 (5)
Z2
Radiation typeMo Kα
µ (mm1)0.33
Crystal size (mm)0.25 × 0.20 × 0.08
Data collection
DiffractometerBruker Kappa APEXII CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.982, 0.988
No. of measured, independent and
observed [I > 2σ(I)] reflections
8832, 2125, 1721
Rint0.032
(sin θ/λ)max1)0.600
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.101, 1.06
No. of reflections2125
No. of parameters164
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.22, 0.16

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N5—H5A···N10.862.172.775 (2)127
N5—H5B···O20.862.402.942 (2)122
N5—H5B···N2i0.862.413.017 (2)128
C5—H5···N4ii0.932.533.313 (2)142
Symmetry codes: (i) x+2, y+1, z; (ii) x, y+2, z.
 

Acknowledgements

The authors acknowledge the provision of funds for the purchase of the diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha, Pakistan. They also acknowledge the technical support provided by Bana Inter­national, Karachi, Pakistan.

References

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