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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 69| Part 7| July 2013| Page o1141
https://doi.org/10.1107/S1600536813016917

N′-[(E)-4-Bromo­benzyl­­idene]pyrazine-2-carbohydrazide

Shahid Hameed,a Mushtaq Ahmad,a,b M. Nawaz Tahir,c* Muhammad Abdullah Shahd and Hazoor Ahmad Shade

aDepartment of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan, bMedicinal Botanic Centre, PCSIR Laboratories Complex, Peshawar, Pakistan, cDepartment of Physics, University of Sargodha, Sargodha, Pakistan, dDepartment of Chemistry, University of Hazara, Mansehra, Pakistan, and eDepartment of Chemistry, University of Sargodha, Sargodha, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 13 June 2013; accepted 18 June 2013; online 22 June 2013)

In the title compound, C12H9BrN4O, the N′-methyl­idene­pyrazine-2-carbohydrazide and 4-bromobenzene groups are oriented at a dihedral angle of 10.57 (7)°. The hydrazide N—H group is involved in intra­molecular N—H⋯N inter­action, which generates an S(5) motif. A short C—H⋯O inter­action is formed between the methyl­idene H atom and the carbonyl O atom. It connects mol­ecules into chains extending along [100]. In addition, mol­ecules are arranged into stacks extending along [010] via π–π inter­actions between pyrazine and benzene rings, with centroid–centroid distances of 3.837 (2) and 3.860 (2) Å.

Related literature

For a related crystal structure and related studies, see: Hearn & Cynamon (2004[Hearn, M. J. & Cynamon, M. H. (2004). J. Antimicrob. Chemother. 53, 185-191.]); Jin et al. (2006[Jin, L., Chen, J., Song, B., Chen, Z., Yang, S., Li, Q., Hu, D. & Xu, R. (2006). Bioorg. Med. Chem. Lett. 16, 5036-5040.]); Yuan et al. (2006[Yuan, C.-C., Wu, L., Xing, Z.-Y. & Shi, X.-F. (2006). Acta Cryst. E62, o3274-o3275.]). 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

  • C12H9BrN4O

  • Mr = 305.14

  • Triclinic, [P \overline 1]

  • a = 5.8947 (9) Å

  • b = 7.6941 (12) Å

  • c = 14.029 (2) Å

  • α = 83.273 (7)°

  • β = 80.086 (7)°

  • γ = 72.440 (6)°

  • V = 596.11 (16) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 3.44 mm−1

  • T = 296 K

  • 0.26 × 0.22 × 0.20 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 = 0.425, Tmax = 0.503

  • 7382 measured reflections

  • 2529 independent reflections

  • 1403 reflections with I > 2σ(I)

  • Rint = 0.074
Refinement

  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.084

  • S = 0.94

  • 2529 reflections

  • 163 parameters

  • H-atom parameters constrained

  • Δρmax = 0.28 e Å−3

  • Δρmin = −0.30 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C6—H6⋯O1i 0.93 2.24 3.132 (4) 161
N3—H3A⋯N1 0.86 2.27 2.671 (3) 108
Symmetry code: (i) x+1, y, z.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). 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 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536813016917/gk2580sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536813016917/gk2580Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536813016917/gk2580Isup3.cml

checkCIF report


Comment top

The title compound (Fig. 1) was prepared to study biological activities of hydrazone compounds (Hearn & Cynamon, 2004; Jin et al., 2006).

Crystals of the earlier reported 4-chlorobenzaldehyde(pyrazine-2-carbonyl) hydrazone (Yuan et al., 2006) are practically isostructural with the title compound.

In the title compound the N'-methylidenepyrazine-2-carbohydrazide (A) (C1–C6/N1–N4/O1) and 4-bromophenyl (B) (C7–C12/Br1) moieties are almost planar with r. m. s. deviations of 0.061 Å and 0.009 Å, respectively. The dihedral angle between A/B is 10.57 (7)°. There exists intramolecular N—H···.N hydrogen bond (Table 1, Fig. 2) forming S(5) motif (Bernstein et al., 1995). The intermolecular hydrogen bonds of C—H···.O type (Table 1, Fig. 2) generate C(6) chains (Bernstein et al., 1995) along the crystallographic a-axis. There exist π–π interactions with a distance of 3.838 (2) Å [Cg1—Cg2i & Cg2— Cg1i: i = -x, 2 - y, -z] and 3.860 (2) Å [Cg1—Cg2ii & Cg2—Cg1ii: ii = -x, 1 - y, -z], between the centroids of pyrazine (Cg1) and benzene (Cg2) rings.

Related literature top

For a related crystal structure and related studies, see: Hearn & Cynamon (2004); Jin et al. (2006); Yuan et al. (2006). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

The title compound was prepared by the condensation of equimolar ratio of pyrazine-2-carbohydrazide (0.50 g, 3.6 mmol) and 4-bromobenzaldehyde (0.67 g, 3.6 mmol) in methanol by the reflux of 5 h. The resulting reaction mixture was allowed to cool over night. The precipitated solid was filtered, washed with petroleum ether and recrystalized from chloroform in petroleum ether and dried under reduced pressure over CaCl2 to give white prisms. Rf: 0.40 (30% acetone in petroleum ether): Yield: 83%, soluble in chloroform; m.p. 546–547 K.

Refinement top

The H atoms were positioned geometrically (N–H = 0.86 Å, C–H = 0.93 Å) and refined as riding on their carriers with Uiso(H) = xUeq(C, N), where x = 1.2 for all H-atoms.

Structure description top

The title compound (Fig. 1) was prepared to study biological activities of hydrazone compounds (Hearn & Cynamon, 2004; Jin et al., 2006).

Crystals of the earlier reported 4-chlorobenzaldehyde(pyrazine-2-carbonyl) hydrazone (Yuan et al., 2006) are practically isostructural with the title compound.

In the title compound the N'-methylidenepyrazine-2-carbohydrazide (A) (C1–C6/N1–N4/O1) and 4-bromophenyl (B) (C7–C12/Br1) moieties are almost planar with r. m. s. deviations of 0.061 Å and 0.009 Å, respectively. The dihedral angle between A/B is 10.57 (7)°. There exists intramolecular N—H···.N hydrogen bond (Table 1, Fig. 2) forming S(5) motif (Bernstein et al., 1995). The intermolecular hydrogen bonds of C—H···.O type (Table 1, Fig. 2) generate C(6) chains (Bernstein et al., 1995) along the crystallographic a-axis. There exist π–π interactions with a distance of 3.838 (2) Å [Cg1—Cg2i & Cg2— Cg1i: i = -x, 2 - y, -z] and 3.860 (2) Å [Cg1—Cg2ii & Cg2—Cg1ii: ii = -x, 1 - y, -z], between the centroids of pyrazine (Cg1) and benzene (Cg2) rings.

For a related crystal structure and related studies, see: Hearn & Cynamon (2004); Jin et al. (2006); Yuan et al. (2006). For graph-set notation, see: Bernstein et al. (1995).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. View of the title compound with the displacement ellipsoids drawn at the 50% probability level. H atoms are shown by small circles of arbitrary radii.
[Figure 2] Fig. 2. Packing diagram of the title compound showing S(5) motif and C(6) chains along [1 0 0].
N'-[(E)-4-Bromobenzylidene]pyrazine-2-carbohydrazide top
Crystal data top
C12H9BrN4OZ = 2
Mr = 305.14F(000) = 304
Triclinic, P1Dx = 1.700 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 5.8947 (9) ÅCell parameters from 1403 reflections
b = 7.6941 (12) Åθ = 2.1–25.5°
c = 14.029 (2) ŵ = 3.44 mm−1
α = 83.273 (7)°T = 296 K
β = 80.086 (7)°Prism, white
γ = 72.440 (6)°0.26 × 0.22 × 0.20 mm
V = 596.11 (16) Å3
Data collection top
Bruker Kappa APEXII CCD
diffractometer		2529 independent reflections
Radiation source: fine-focus sealed tube1403 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.074
Detector resolution: 8.10 pixels mm-1θmax = 27.1°, θmin = 1.5°
ω scansh = −7→6
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		k = −9→9
Tmin = 0.425, Tmax = 0.503l = −17→17
7382 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)] = 0.039Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.084H-atom parameters constrained
S = 0.94 w = 1/[σ2(Fo2) + (0.0355P)2]
where P = (Fo2 + 2Fc2)/3
2529 reflections(Δ/σ)max < 0.001
163 parametersΔρmax = 0.28 e Å−3
0 restraintsΔρmin = −0.30 e Å−3
Crystal data top
C12H9BrN4Oγ = 72.440 (6)°
Mr = 305.14V = 596.11 (16) Å3
Triclinic, P1Z = 2
a = 5.8947 (9) ÅMo Kα radiation
b = 7.6941 (12) ŵ = 3.44 mm−1
c = 14.029 (2) ÅT = 296 K
α = 83.273 (7)°0.26 × 0.22 × 0.20 mm
β = 80.086 (7)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer		2529 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		1403 reflections with I > 2σ(I)
Tmin = 0.425, Tmax = 0.503Rint = 0.074
7382 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.084H-atom parameters constrained
S = 0.94Δρmax = 0.28 e Å−3
2529 reflectionsΔρmin = −0.30 e Å−3
163 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
xyzUiso*/Ueq
Br10.36405 (7)0.25644 (5)0.47485 (3)0.07332 (19)
O1−0.4594 (4)0.8146 (3)−0.03918 (16)0.0633 (7)
N1−0.0274 (4)0.9547 (3)−0.21291 (18)0.0486 (7)
N2−0.4307 (5)1.1093 (4)−0.3071 (2)0.0599 (8)
N3−0.0701 (5)0.7949 (3)−0.03380 (18)0.0523 (7)
H3A0.05650.8198−0.06490.063*
N4−0.0613 (5)0.7038 (3)0.05682 (19)0.0508 (7)
C1−0.2458 (5)0.9456 (4)−0.1727 (2)0.0401 (8)
C2−0.0148 (6)1.0405 (4)−0.3008 (2)0.0538 (9)
H20.13371.0501−0.33210.065*
C3−0.2126 (6)1.1151 (4)−0.3467 (2)0.0549 (9)
H3−0.19271.1724−0.40840.066*
C4−0.4426 (6)1.0230 (4)−0.2191 (3)0.0540 (9)
H4−0.59181.0148−0.18770.065*
C5−0.2732 (6)0.8455 (4)−0.0745 (2)0.0476 (8)
C60.1460 (6)0.6511 (4)0.0827 (2)0.0496 (9)
H60.27480.67340.03980.060*
C70.1898 (6)0.5575 (4)0.1764 (2)0.0449 (8)
C80.0083 (6)0.5360 (4)0.2494 (2)0.0496 (8)
H8−0.15090.58330.23860.060*
C90.0571 (6)0.4466 (4)0.3372 (2)0.0524 (9)
H9−0.06790.43390.38530.063*
C100.2919 (6)0.3757 (4)0.3537 (2)0.0500 (8)
C110.4775 (6)0.3941 (4)0.2827 (2)0.0555 (9)
H110.63610.34550.29390.067*
C120.4264 (6)0.4854 (4)0.1945 (2)0.0543 (9)
H120.55160.49890.14670.065*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0815 (3)0.0777 (3)0.0601 (3)−0.0224 (2)−0.0225 (2)0.01461 (19)
O10.0580 (15)0.0762 (17)0.0622 (15)−0.0398 (13)0.0071 (13)0.0006 (12)
N10.0420 (16)0.0576 (17)0.0482 (17)−0.0216 (13)−0.0063 (13)0.0069 (13)
N20.0479 (18)0.070 (2)0.064 (2)−0.0208 (15)−0.0186 (16)0.0107 (15)
N30.0564 (19)0.0604 (18)0.0429 (16)−0.0271 (14)−0.0057 (15)0.0106 (13)
N40.0555 (19)0.0552 (17)0.0433 (17)−0.0238 (14)−0.0035 (14)0.0059 (13)
C10.0373 (19)0.0392 (18)0.0455 (19)−0.0143 (15)−0.0058 (16)−0.0009 (14)
C20.048 (2)0.066 (2)0.050 (2)−0.0259 (17)−0.0076 (18)0.0125 (17)
C30.057 (2)0.061 (2)0.051 (2)−0.0225 (18)−0.0159 (19)0.0060 (17)
C40.041 (2)0.062 (2)0.062 (2)−0.0221 (17)−0.0034 (18)−0.0014 (18)
C50.052 (2)0.047 (2)0.048 (2)−0.0234 (17)−0.0001 (18)−0.0048 (16)
C60.055 (2)0.053 (2)0.045 (2)−0.0293 (17)−0.0008 (18)0.0027 (16)
C70.048 (2)0.0429 (18)0.048 (2)−0.0225 (15)−0.0039 (17)−0.0031 (15)
C80.0401 (19)0.053 (2)0.057 (2)−0.0192 (16)−0.0062 (17)0.0068 (17)
C90.048 (2)0.059 (2)0.051 (2)−0.0221 (17)−0.0024 (18)0.0051 (17)
C100.052 (2)0.049 (2)0.051 (2)−0.0199 (16)−0.0092 (18)0.0019 (15)
C110.043 (2)0.060 (2)0.065 (2)−0.0157 (17)−0.0119 (19)−0.0025 (18)
C120.048 (2)0.064 (2)0.054 (2)−0.0247 (17)0.0008 (18)−0.0048 (18)
Geometric parameters (Å, º) top
Br1—C101.886 (3)C3—H30.9300
O1—C51.204 (3)C4—H40.9300
N1—C21.329 (4)C6—C71.447 (4)
N1—C11.332 (3)C6—H60.9300
N2—C31.322 (4)C7—C81.383 (4)
N2—C41.332 (4)C7—C121.393 (4)
N3—C51.346 (4)C8—C91.370 (4)
N3—N41.379 (3)C8—H80.9300
N3—H3A0.8600C9—C101.376 (4)
N4—C61.268 (4)C9—H90.9300
C1—C41.370 (4)C10—C111.377 (4)
C1—C51.506 (4)C11—C121.382 (4)
C2—C31.368 (4)C11—H110.9300
C2—H20.9300C12—H120.9300
C2—N1—C1115.4 (3)N4—C6—C7122.5 (3)
C3—N2—C4114.6 (3)N4—C6—H6118.7
C5—N3—N4121.3 (3)C7—C6—H6118.7
C5—N3—H3A119.4C8—C7—C12117.9 (3)
N4—N3—H3A119.4C8—C7—C6123.3 (3)
C6—N4—N3114.5 (3)C12—C7—C6118.7 (3)
N1—C1—C4121.5 (3)C9—C8—C7121.6 (3)
N1—C1—C5118.5 (3)C9—C8—H8119.2
C4—C1—C5119.9 (3)C7—C8—H8119.2
N1—C2—C3122.4 (3)C8—C9—C10119.7 (3)
N1—C2—H2118.8C8—C9—H9120.2
C3—C2—H2118.8C10—C9—H9120.2
N2—C3—C2122.8 (3)C9—C10—C11120.4 (3)
N2—C3—H3118.6C9—C10—Br1120.6 (3)
C2—C3—H3118.6C11—C10—Br1119.0 (3)
N2—C4—C1123.2 (3)C10—C11—C12119.5 (3)
N2—C4—H4118.4C10—C11—H11120.2
C1—C4—H4118.4C12—C11—H11120.2
O1—C5—N3125.4 (3)C11—C12—C7120.9 (3)
O1—C5—C1121.7 (3)C11—C12—H12119.6
N3—C5—C1112.9 (3)C7—C12—H12119.6
C5—N3—N4—C6174.4 (3)C4—C1—C5—N3−173.2 (3)
C2—N1—C1—C4−1.1 (4)N3—N4—C6—C7178.3 (3)
C2—N1—C1—C5178.2 (3)N4—C6—C7—C8−7.6 (5)
C1—N1—C2—C30.3 (5)N4—C6—C7—C12172.5 (3)
C4—N2—C3—C2−0.7 (5)C12—C7—C8—C9−0.1 (5)
N1—C2—C3—N20.7 (5)C6—C7—C8—C9−180.0 (3)
C3—N2—C4—C1−0.1 (5)C7—C8—C9—C10−0.1 (5)
N1—C1—C4—N21.0 (5)C8—C9—C10—C110.0 (5)
C5—C1—C4—N2−178.2 (3)C8—C9—C10—Br1178.7 (2)
N4—N3—C5—O1−1.9 (5)C9—C10—C11—C120.4 (5)
N4—N3—C5—C1179.1 (2)Br1—C10—C11—C12−178.3 (2)
N1—C1—C5—O1−171.5 (3)C10—C11—C12—C7−0.6 (5)
C4—C1—C5—O17.8 (5)C8—C7—C12—C110.5 (5)
N1—C1—C5—N37.6 (4)C6—C7—C12—C11−179.7 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···O1i0.932.243.132 (4)161
N3—H3A···N10.862.272.671 (3)108
Symmetry code: (i) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC12H9BrN4O
Mr305.14
Crystal system, space groupTriclinic, P1
Temperature (K)296
a, b, c (Å)5.8947 (9), 7.6941 (12), 14.029 (2)
α, β, γ (°)83.273 (7), 80.086 (7), 72.440 (6)
V (Å3)596.11 (16)
Z2
Radiation typeMo Kα
µ (mm−1)3.44
Crystal size (mm)0.26 × 0.22 × 0.20
Data collection
DiffractometerBruker Kappa APEXII CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.425, 0.503
No. of measured, independent and
observed [I > 2σ(I)] reflections		7382, 2529, 1403
Rint0.074
(sin θ/λ)max (Å−1)0.640
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.084, 0.94
No. of reflections2529
No. of parameters163
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.28, −0.30

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009), WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···O1i0.932.243.132 (4)161
N3—H3A···N10.862.272.671 (3)108
Symmetry code: (i) x+1, y, z.
 

Acknowledgements

The authors acknowledge the provision of funds for the purchase of a diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha, Pakistan. The authors are also thankful to the Higher Education Commission (HEC) of Pakistan for financial support. MA is also thankful to the Pakistan Council of Scientific and Industrial Research (PCSIR) Laboratories of Pakistan for financial support throughout his study leave.

References

First citationBernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573.  CrossRef CAS Web of Science Google Scholar
 First citationBruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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ISSN: 2056-9890
Volume 69| Part 7| July 2013| Page o1141
https://doi.org/10.1107/S1600536813016917
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