5-Amino-3-anilino-1H-pyrazole-4-carbonitrile

Mohamed, S.K.; Akkurt, M.; Fronczek, F.R.; El-Remaily, M.A.A.; Abdelhamid, A.A.

doi:10.1107/S1600536812036045

organic compounds

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Volume 68| Part 9| September 2012| Page o2784

doi:10.1107/S1600536812036045

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5-Amino-3-anilino-1H-pyrazole-4-carbonitrile

Shaaban K. Mohamed,^a Mehmet Akkurt,^b ^* Frank R. Fronczek,^c Mahmoud A. A. El-Remaily ^d and Antar A. Abdelhamid ^a

^aChemistry and Environmental Division, Manchester Metropolitan University, Manchester M1 5GD, England, ^bDepartment of Physics, Faculty of Sciences, Erciyes University, 38039 Kayseri, Turkey, ^cDepartment of Chemistry, Louisiana State University, Baton Rouge, LA 70803-1804, USA, and ^dDepartment of Chemistry, Faculty of Science, Sohag University, 82524 Sohag, Egypt
^*Correspondence e-mail: akkurt@erciyes.edu.tr

(Received 14 August 2012; accepted 16 August 2012; online 25 August 2012)

In the title compound, C₁₀H₉N₅, the phenyl ring is twisted with respect to the pyrazole ring, forming a dihedral angle of 24.00 (6)°. In the crystal, molecules are linked by N—H⋯N hydrogen bonds into chains running parallel to [010] containing alternating R₂²(6) and R₂²(12) rings. Further interactions are found in the crystal, viz. N—H⋯π(phenyl) interactions and weak face-to-face π–π stacking interactions [centroid–centroid distance = 3.8890 (6) Å] between the centroids of the pyrazole and phenyl rings are observed.

Related literature

For biological activities of pyrazoles, see: Kaushik et al. (2010 ); Sheikh et al. (2009 ); Krishnamurthy et al. (2004 ); Grimmett (1970 ). For the use of related compounds as bridging ligands, see: Lynch & McClenaghan (2005 ). For the synthesis of the title compound, see: Soliman et al. (2010 ). For hydrogen-bond motifs, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₁₀H₉N₅
M_r = 199.22
Orthorhombic, P 2₁ 2₁ 2₁
a = 6.3441 (1) Å
b = 11.1354 (2) Å
c = 13.7754 (3) Å
V = 973.15 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 90 K
0.25 × 0.17 × 0.08 mm

Data collection

Bruker Kappa APEXII DUO diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2004 ) T_min = 0.978, T_max = 0.993
32878 measured reflections
2975 independent reflections
2767 reflections with I > 2σ(I)
R_int = 0.035
Standard reflections: 0

Refinement

R[F² > 2σ(F²)] = 0.033
wR(F²) = 0.086
S = 1.09
2975 reflections
152 parameters
4 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.32 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of the C1–C6 phenyl ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N⋯N5ⁱ	0.84 (2)	2.15 (2)	2.9934 (13)	179 (2)
N3—H3N⋯N2ⁱⁱ	0.87 (2)	2.09 (2)	2.8947 (13)	154 (2)
N4—H12⋯Cg2ⁱⁱⁱ	0.85 (2)	2.51 (2)	3.2011 (12)	140 (2)
Symmetry codes: (i) $[x-{\script{1\over 2}}, -y-{\script{1\over 2}}, -z+2]$ ; (ii) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+2]$ ; (iii) $[-x+{\script{3\over 2}}, -y, z+{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SIR97 (Altomare et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ) and PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812036045/tk5143sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812036045/tk5143Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812036045/tk5143Isup3.cml

checkCIF report

Comment top

The interest in pyrazole compounds stems from their pharmaceutical and agricultural applications such as drugs, dyes and anaesthetics (Grimmett, 1970; Sheikh et al., 2009; Kaushik et al., 2010; Krishnamurthy et al., 2004). In addition, such pyrazoles and related compounds are common molecules used in coordination or organometallic chemistry as bridging ligands, utilizing the ring positions of the two N atoms (Lynch & McClenaghan, 2005). We report herein the crystal structure of the title compound which was synthesized by our team as a precursor having two functional substituents (amino and nitrile groups) for the purposes of synthesis of multi-fused pyrazolo-heterocyclic compounds such as nitrogen bridgehead derivatives having potential biological activities (Soliman et al., 2010).

In the molecule of the title compound, (Fig. 1), the phenyl and 1H-pyrazole ring makes a dihedral angle of 24.00 (6)° with each other.

The crystal structure is stabilized by N—H···N hydrogen bonds (Table 1, Fig. 2) which link the molecules into chains running parallel to [010] with alternating R₂²(6) and R₂²(12) motifs (Bernstein et al., 1995). In addition, the crystal structure exhibits N—H···π(phenyl) interactions, Table 1, and weak face-to-face π—π stacking interactions [Cg1···Cg2 (1 + x, y, z) = 3.8890 (6) Å; where Cg1 and Cg2 are the centroid of the (N2/N3/C7–C9) 1H-pyrazole and (C1–C6) phenyl rings].

Related literature top

For biological activities of pyrazoles, see: Kaushik et al. (2010); Sheikh et al. (2009); Krishnamurthy et al. (2004); Grimmett (1970). For related literature, see: Lynch & McClenaghan (2005). For the synthesis of the title compound, see: Soliman et al. (2010). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

The title compound was prepared according to the literature procedure (Soliman et al., 2010). Crystals were obtained from an ethanol solution of (I) by slow evaporation (M.pt: 481 K).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top

The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids for non-H atoms are drawn at the 50% probability level.

View of chains of the dimers formed by pairs of N—H···N hydrogen bonds, with the R₂²(12) and R₂²(6) motifs connected into a supramolecular chain. H atoms not involved in hydrogen bonds have been omitted for clarity.

5-Amino-3-anilino-1H-pyrazole-4-carbonitrile top

Crystal data top

C₁₀H₉N₅	F(000) = 416
M_r = 199.22	D_x = 1.360 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 9908 reflections
a = 6.3441 (1) Å	θ = 2.4–30.5°
b = 11.1354 (2) Å	µ = 0.09 mm⁻¹
c = 13.7754 (3) Å	T = 90 K
V = 973.15 (3) Å³	Plate, colourless
Z = 4	0.25 × 0.17 × 0.08 mm

Data collection top

Bruker Kappa APEXII DUO diffractometer	2975 independent reflections
Radiation source: fine-focus sealed tube	2767 reflections with I > 2σ(I)
TRIUMPH curved graphite monochromator	R_int = 0.035
ϕ and ω scans	θ_max = 30.6°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	h = −9→9
T_min = 0.978, T_max = 0.993	k = −15→15
32878 measured reflections	l = −19→19

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.033	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.086	w = 1/[σ²(F_o²) + (0.0494P)² + 0.1533P] where P = (F_o² + 2F_c²)/3
S = 1.09	(Δ/σ)_max = 0.001
2975 reflections	Δρ_max = 0.32 e Å⁻³
152 parameters	Δρ_min = −0.20 e Å⁻³
4 restraints	Absolute structure: nd
Primary atom site location: structure-invariant direct methods

Crystal data top

C₁₀H₉N₅	V = 973.15 (3) Å³
M_r = 199.22	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 6.3441 (1) Å	µ = 0.09 mm⁻¹
b = 11.1354 (2) Å	T = 90 K
c = 13.7754 (3) Å	0.25 × 0.17 × 0.08 mm

Data collection top

Bruker Kappa APEXII DUO diffractometer	2975 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	2767 reflections with I > 2σ(I)
T_min = 0.978, T_max = 0.993	R_int = 0.035
32878 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.033	4 restraints
wR(F²) = 0.086	H atoms treated by a mixture of independent and constrained refinement
S = 1.09	Δρ_max = 0.32 e Å⁻³
2975 reflections	Δρ_min = −0.20 e Å⁻³
152 parameters	Absolute structure: nd

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 on F² for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The observed criterion of F² > σ(F²) is used only for calculating -R-factor-obs 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
N1	0.50345 (15)	−0.01004 (8)	0.89839 (7)	0.0142 (2)
N2	0.71282 (15)	0.15769 (8)	0.94613 (7)	0.0154 (2)
N3	0.89266 (15)	0.16812 (8)	1.00299 (7)	0.0168 (2)
N4	1.13973 (17)	0.05235 (10)	1.09010 (8)	0.0234 (3)
N5	0.84875 (15)	−0.24944 (9)	1.03572 (7)	0.0204 (3)
C1	0.40580 (18)	0.15607 (10)	0.78868 (8)	0.0173 (3)
C2	0.2548 (2)	0.20761 (11)	0.72811 (8)	0.0205 (3)
C3	0.06057 (19)	0.15345 (11)	0.71341 (8)	0.0213 (3)
C4	0.01783 (19)	0.04497 (11)	0.75945 (8)	0.0193 (3)
C5	0.16597 (18)	−0.00746 (10)	0.82040 (7)	0.0152 (3)
C6	0.36064 (16)	0.04854 (9)	0.83683 (7)	0.0130 (2)
C7	0.66942 (16)	0.04110 (9)	0.94711 (7)	0.0122 (2)
C8	0.81769 (17)	−0.02408 (9)	1.00460 (8)	0.0133 (2)
C9	0.96026 (17)	0.06332 (10)	1.03764 (8)	0.0153 (3)
C10	0.83277 (17)	−0.14847 (9)	1.02122 (7)	0.0145 (2)
H1	0.53600	0.19300	0.79700	0.0210*
H1N	0.459 (3)	−0.0771 (13)	0.9176 (12)	0.027 (4)*
H2	0.28480	0.27970	0.69700	0.0250*
H3	−0.03960	0.18910	0.67340	0.0260*
H3N	0.958 (3)	0.2358 (13)	1.0116 (14)	0.034 (5)*
H4	−0.11110	0.00720	0.74930	0.0230*
H5	0.13580	−0.08020	0.85050	0.0180*
H11	1.200 (3)	0.1170 (14)	1.1129 (13)	0.038 (5)*
H12	1.165 (3)	−0.0151 (14)	1.1162 (13)	0.036 (5)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0145 (4)	0.0093 (4)	0.0189 (4)	−0.0012 (3)	−0.0034 (4)	0.0031 (3)
N2	0.0152 (4)	0.0112 (4)	0.0197 (4)	−0.0003 (3)	−0.0030 (3)	−0.0012 (3)
N3	0.0178 (4)	0.0117 (4)	0.0208 (4)	−0.0023 (3)	−0.0038 (3)	−0.0005 (3)
N4	0.0219 (5)	0.0230 (5)	0.0253 (5)	−0.0035 (4)	−0.0095 (4)	0.0041 (4)
N5	0.0189 (5)	0.0160 (4)	0.0262 (5)	0.0023 (4)	0.0001 (4)	0.0038 (4)
C1	0.0189 (5)	0.0150 (5)	0.0179 (5)	−0.0012 (4)	−0.0018 (4)	0.0018 (4)
C2	0.0260 (6)	0.0172 (5)	0.0183 (5)	0.0030 (4)	−0.0029 (4)	0.0044 (4)
C3	0.0206 (5)	0.0250 (6)	0.0182 (5)	0.0068 (5)	−0.0037 (4)	0.0018 (4)
C4	0.0144 (5)	0.0251 (5)	0.0184 (5)	0.0007 (4)	−0.0004 (4)	−0.0010 (4)
C5	0.0134 (5)	0.0170 (4)	0.0153 (4)	−0.0011 (4)	0.0010 (4)	0.0006 (4)
C6	0.0136 (4)	0.0126 (4)	0.0129 (4)	0.0025 (4)	−0.0004 (3)	−0.0002 (3)
C7	0.0124 (4)	0.0105 (4)	0.0137 (4)	0.0007 (4)	0.0005 (4)	0.0003 (3)
C8	0.0128 (4)	0.0126 (4)	0.0145 (4)	0.0008 (3)	0.0001 (4)	0.0011 (3)
C9	0.0157 (4)	0.0155 (5)	0.0147 (4)	−0.0005 (4)	0.0002 (3)	0.0004 (4)
C10	0.0125 (4)	0.0164 (4)	0.0147 (4)	0.0011 (4)	0.0008 (3)	0.0017 (3)

Geometric parameters (Å, º) top

N1—C6	1.4020 (14)	C2—C3	1.3868 (17)
N1—C7	1.3724 (14)	C3—C4	1.3910 (17)
N2—N3	1.3888 (14)	C4—C5	1.3889 (16)
N2—C7	1.3272 (13)	C5—C6	1.4019 (15)
N3—C9	1.3318 (14)	C7—C8	1.4279 (15)
N4—C9	1.3541 (15)	C8—C9	1.4044 (15)
N5—C10	1.1464 (14)	C8—C10	1.4072 (14)
N1—H1N	0.841 (15)	C1—H1	0.9300
N3—H3N	0.868 (16)	C2—H2	0.9300
N4—H11	0.874 (17)	C3—H3	0.9300
N4—H12	0.848 (16)	C4—H4	0.9300
C1—C2	1.3940 (16)	C5—H5	0.9300
C1—C6	1.3985 (15)

C6—N1—C7	126.77 (9)	N1—C7—N2	124.06 (9)
N3—N2—C7	104.27 (8)	N1—C7—C8	124.46 (9)
N2—N3—C9	113.17 (9)	C7—C8—C9	104.58 (9)
C6—N1—H1N	112.8 (13)	C7—C8—C10	129.45 (10)
C7—N1—H1N	118.2 (12)	C9—C8—C10	125.85 (10)
N2—N3—H3N	122.8 (12)	N3—C9—N4	122.76 (10)
C9—N3—H3N	123.9 (12)	N3—C9—C8	106.48 (9)
C9—N4—H12	117.7 (12)	N4—C9—C8	130.69 (11)
H11—N4—H12	119.7 (17)	N5—C10—C8	178.64 (11)
C9—N4—H11	119.1 (12)	C2—C1—H1	120.00
C2—C1—C6	119.71 (10)	C6—C1—H1	120.00
C1—C2—C3	121.26 (11)	C1—C2—H2	119.00
C2—C3—C4	118.97 (11)	C3—C2—H2	119.00
C3—C4—C5	120.58 (11)	C2—C3—H3	121.00
C4—C5—C6	120.45 (10)	C4—C3—H3	121.00
N1—C6—C1	123.57 (9)	C3—C4—H4	120.00
N1—C6—C5	117.39 (9)	C5—C4—H4	120.00
C1—C6—C5	119.00 (9)	C4—C5—H5	120.00
N2—C7—C8	111.48 (9)	C6—C5—H5	120.00

C7—N1—C6—C5	−159.01 (10)	C2—C3—C4—C5	0.99 (17)
C6—N1—C7—N2	3.39 (17)	C3—C4—C5—C6	0.32 (16)
C7—N1—C6—C1	23.65 (16)	C4—C5—C6—C1	−1.90 (15)
C6—N1—C7—C8	−176.20 (10)	C4—C5—C6—N1	−179.36 (10)
C7—N2—N3—C9	0.38 (12)	N1—C7—C8—C9	178.44 (10)
N3—N2—C7—C8	0.53 (12)	N2—C7—C8—C10	−177.26 (11)
N3—N2—C7—N1	−179.10 (10)	N1—C7—C8—C10	2.37 (18)
N2—N3—C9—N4	176.12 (10)	N2—C7—C8—C9	−1.19 (12)
N2—N3—C9—C8	−1.13 (13)	C7—C8—C9—N3	1.35 (12)
C6—C1—C2—C3	−0.88 (17)	C10—C8—C9—N4	0.7 (2)
C2—C1—C6—N1	179.46 (10)	C7—C8—C9—N4	−175.60 (12)
C2—C1—C6—C5	2.16 (16)	C10—C8—C9—N3	177.60 (10)
C1—C2—C3—C4	−0.71 (17)

Hydrogen-bond geometry (Å, º) top

Cg2 is the centroid of the C1–C6 phenyl ring.

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···N5ⁱ	0.84 (2)	2.15 (2)	2.9934 (13)	179 (2)
N3—H3N···N2ⁱⁱ	0.87 (2)	2.09 (2)	2.8947 (13)	154 (2)
C1—H1···N2	0.93	2.37	2.9152 (15)	117
N4—H12···Cg2ⁱⁱⁱ	0.85 (2)	2.51 (2)	3.2011 (12)	140 (2)

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

Experimental details

Crystal data
Chemical formula	C₁₀H₉N₅
M_r	199.22
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	90
a, b, c (Å)	6.3441 (1), 11.1354 (2), 13.7754 (3)
V (Å³)	973.15 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.25 × 0.17 × 0.08

Data collection
Diffractometer	Bruker Kappa APEXII DUO diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2004)
T_min, T_max	0.978, 0.993
No. of measured, independent and observed [I > 2σ(I)] reflections	32878, 2975, 2767
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.715

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.086, 1.09
No. of reflections	2975
No. of parameters	152
No. of restraints	4
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.32, −0.20
Absolute structure	Nd

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

Cg2 is the centroid of the C1–C6 phenyl ring.

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···N5ⁱ	0.841 (15)	2.153 (15)	2.9934 (13)	178.8 (15)
N3—H3N···N2ⁱⁱ	0.868 (16)	2.088 (18)	2.8947 (13)	154.3 (16)
N4—H12···Cg2ⁱⁱⁱ	0.848 (16)	2.506 (18)	3.2011 (12)	139.9 (15)

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

Acknowledgements

We thank Sohag University for financial support of this project. Manchester Metropolitan University, Erciyes University and Louisiana State University are gratefully acknowledged for supporting this study.

References

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ISSN: 2056-9890

Volume 68| Part 9| September 2012| Page o2784

doi:10.1107/S1600536812036045

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