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Acta Cryst. (2007). E63, o2888    [ doi:10.1107/S1600536807022039 ]

4-Hydroxy-3-methoxybenzaldehyde (pyrazin-2-yl)hydrazone

C.-Y. Liu, J. Hu, Y.-Q. Zhang, Z.-C. Zhu and M.-J. Zhang

Abstract top

The asymmetric unit of the title compound, C12H12N4O2, contains two independent molecules. The dihedral angles between the planar rings of the two molecules are 7.72 (3) and 40.24 (2)°. In the crystal structure, intramolecular O-H...O and intermolecular O-H...O, O-H...N and N-H...N hydrogen bonds form a network structure.

Comment top

In recent years, Schiff bases are applied in medicine (Desai et al., 2001), catalytic chemistry (Isse et al., 1997), analytical chemistry (Bastos et al., 2000), corrosion (Ma et al., 2001) and photochromism (Zhao et al., 2001). The crystal structure determination of the title compound, (I), was carried out in order to elucidate its molecular conformation.

In the molecule of the title compound, (I), (Fig. 1), the asymmetric unit contains two independent molecules and the bond lengths and angles (Table 1) are within normal ranges (Allen et al., 1987).

Rings A (N1/N2/C1—C4), B (C6—C11), C (N5/N6/C13—C16) and D (C18—C23) are, of course, planar and the dihedral angles between them are A/B = 7.72 (3)° and C/D = 40.24 (2)°.

As can be seen from the packing diagram (Fig. 2), the intramolecular O—H···O and intermolecular O—H···O, O—H···N and N—H···N hydrogen bonds (Table 2) cause to the formation of a network structure, in which they may be effective in the stabilization of the crystal structure. Dipol-dipol and van der Waals interactions are also effective in the molecular packing.

Related literature top

For general backgroud, see: Desai et al. (2001); Isse et al. (1997); Bastos et al. (2000); Ma et al. (2001); Zhao et al. (2001); Allen et al. (1987); Kim et al. (2005).

Experimental top

The title compound, (I), was synthesized by the reaction of 2-hydrazinopyrazine (100.0 mg, 0.91 mmol) (Kim et al., 2005) with 3-methoxy-4-hydroxybenzaldehyde (138.2 mg, 0.91 mmol) in methanol (25 ml). The mixture was stirred and refluxed for 2 h, producing a light-yellow solution. Single crystals of (I) were obtained by slow evaporation of the methanol solution in 15 d (yield; 82.2 mg, 37%, m.p. 469–471 K).

Refinement top

H atoms were positioned geometrically, with O—H = 0.82 Å (for OH), N—H = 0.86 Å (for NH) and C—H = 0.93 and 0.96 Å for aromatic and methyl H, respectively, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C,O,N), where x = 1.5 for OH and methyl H and x = 1.2 for all other H atoms.

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997); software used to prepare material for publication: SHELXTL.

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. A packing diagram for (I). Hydrogen bonds are shown as dashed lines.
4-Hydroxy-3-methoxybenzaldehyde (pyrazin-2-yl)hydrazone top
Crystal data top
C12H12N4O2F(000) = 2048
Mr = 244.26Dx = 1.389 Mg m−3
Monoclinic, C2/cMelting point: 196 K
Hall symbol: -C 2ycMo Kα radiation, λ = 0.71073 Å
a = 43.862 (6) ÅCell parameters from 2951 reflections
b = 7.9026 (11) Åθ = 2.8–23.3°
c = 13.4958 (19) ŵ = 0.10 mm−1
β = 92.783 (3)°T = 294 K
V = 4672.4 (11) Å3Prism, orange
Z = 160.24 × 0.20 × 0.12 mm
Data collection top
Bruker CCD area-detector
diffractometer		4741 independent reflections
Radiation source: fine-focus sealed tube2870 reflections with I > 2σ(I)
graphiteRint = 0.038
φ and ω scansθmax = 26.4°, θmin = 0.9°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −45→54
Tmin = 0.977, Tmax = 0.988k = −9→9
12989 measured reflectionsl = −12→16
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)] = 0.042Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.118H-atom parameters constrained
S = 0.99 w = 1/[σ2(Fo2) + (0.056P)2 + 1.0712P]
where P = (Fo2 + 2Fc2)/3
4741 reflections(Δ/σ)max = 0.001
329 parametersΔρmax = 0.21 e Å−3
0 restraintsΔρmin = −0.20 e Å−3
Crystal data top
C12H12N4O2V = 4672.4 (11) Å3
Mr = 244.26Z = 16
Monoclinic, C2/cMo Kα radiation
a = 43.862 (6) ŵ = 0.10 mm−1
b = 7.9026 (11) ÅT = 294 K
c = 13.4958 (19) Å0.24 × 0.20 × 0.12 mm
β = 92.783 (3)°
Data collection top
Bruker CCD area-detector
diffractometer		4741 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		2870 reflections with I > 2σ(I)
Tmin = 0.977, Tmax = 0.988Rint = 0.038
12989 measured reflectionsθmax = 26.4°
Refinement top
R[F2 > 2σ(F2)] = 0.042H-atom parameters constrained
wR(F2) = 0.118Δρmax = 0.21 e Å−3
S = 0.99Δρmin = −0.20 e Å−3
4741 reflectionsAbsolute structure: ?
329 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
O10.09624 (3)−0.0018 (2)0.35987 (9)0.0491 (4)
H10.1125−0.04790.34890.074*
O20.12414 (3)−0.05024 (18)0.19008 (9)0.0412 (4)
O30.88212 (3)0.37662 (18)0.52439 (11)0.0522 (4)
H30.89390.44820.50430.078*
O40.84359 (3)0.17444 (17)0.60218 (10)0.0454 (4)
N1−0.07790 (4)0.4233 (2)−0.07185 (13)0.0457 (5)
N2−0.03900 (4)0.3369 (2)−0.21998 (12)0.0424 (4)
N3−0.00114 (4)0.2727 (3)−0.10462 (12)0.0508 (5)
H3B0.01090.2598−0.15250.061*
N40.00922 (4)0.2394 (2)−0.00933 (12)0.0429 (4)
N50.77115 (4)0.2428 (2)1.12707 (13)0.0466 (5)
N60.74870 (4)0.5668 (2)1.08398 (13)0.0432 (4)
N70.78167 (4)0.5929 (2)0.95882 (13)0.0448 (5)
H7A0.77740.69900.95480.054*
N80.80002 (4)0.5187 (2)0.89084 (12)0.0381 (4)
C1−0.06743 (5)0.3908 (3)−0.24004 (16)0.0482 (6)
H1A−0.07440.3999−0.30610.058*
C2−0.08688 (5)0.4334 (3)−0.16788 (17)0.0487 (6)
H2−0.10650.4697−0.18570.058*
C3−0.04997 (4)0.3702 (3)−0.04990 (15)0.0415 (5)
H3A−0.04320.36180.01630.050*
C4−0.03019 (4)0.3260 (3)−0.12424 (14)0.0366 (5)
C50.03653 (5)0.1859 (3)0.00035 (14)0.0407 (5)
H50.04760.1749−0.05630.049*
C60.05136 (4)0.1408 (3)0.09534 (14)0.0369 (5)
C70.03815 (5)0.1649 (3)0.18529 (15)0.0467 (6)
H70.01890.21370.18680.056*
C80.05330 (5)0.1172 (3)0.27277 (15)0.0461 (6)
H80.04420.13430.33280.055*
C90.08172 (5)0.0447 (3)0.27178 (14)0.0367 (5)
C100.09553 (4)0.0212 (2)0.18214 (13)0.0326 (4)
C110.08029 (4)0.0694 (2)0.09510 (14)0.0362 (5)
H110.08950.05400.03520.043*
C120.13893 (5)−0.0775 (3)0.10010 (16)0.0587 (7)
H12A0.1268−0.15180.05810.088*
H12B0.1586−0.12790.11440.088*
H12C0.14150.02870.06700.088*
C130.73840 (5)0.4715 (3)1.15752 (16)0.0477 (6)
H130.72330.51561.19590.057*
C140.74906 (5)0.3134 (3)1.17852 (17)0.0481 (6)
H140.74080.25271.22990.058*
C150.78173 (5)0.3346 (3)1.05504 (15)0.0402 (5)
H150.79720.29041.01820.048*
C160.77044 (4)0.4973 (2)1.03167 (14)0.0345 (5)
C170.81365 (4)0.6185 (3)0.83397 (15)0.0381 (5)
H170.81220.73440.84450.046*
C180.83143 (4)0.5577 (2)0.75289 (14)0.0326 (5)
C190.85151 (4)0.6639 (2)0.70776 (15)0.0371 (5)
H190.85360.77520.72940.045*
C200.86862 (4)0.6076 (2)0.63082 (15)0.0374 (5)
H200.88210.68110.60180.045*
C210.86583 (4)0.4434 (2)0.59665 (14)0.0348 (5)
C220.84495 (4)0.3358 (2)0.64100 (14)0.0336 (5)
C230.82815 (4)0.3918 (2)0.71763 (14)0.0332 (5)
H230.81450.31900.74640.040*
C240.81790 (5)0.0741 (3)0.62537 (17)0.0499 (6)
H24A0.81910.04670.69470.075*
H24B0.8178−0.02830.58710.075*
H24C0.79950.13630.60990.075*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0538 (10)0.0692 (11)0.0248 (7)0.0128 (8)0.0052 (7)0.0060 (7)
O20.0388 (8)0.0572 (9)0.0279 (7)0.0093 (7)0.0034 (6)0.0001 (7)
O30.0597 (10)0.0494 (9)0.0501 (10)−0.0084 (8)0.0303 (8)−0.0047 (8)
O40.0531 (9)0.0357 (8)0.0491 (9)−0.0088 (7)0.0210 (7)−0.0077 (7)
N10.0412 (10)0.0545 (12)0.0422 (11)0.0110 (9)0.0109 (8)0.0045 (9)
N20.0323 (9)0.0624 (12)0.0327 (10)0.0062 (8)0.0026 (7)−0.0010 (9)
N30.0342 (10)0.0897 (15)0.0290 (10)0.0161 (10)0.0063 (8)0.0048 (10)
N40.0385 (10)0.0618 (12)0.0284 (9)0.0046 (9)0.0011 (8)0.0045 (9)
N50.0455 (11)0.0450 (11)0.0494 (11)0.0031 (9)0.0021 (9)0.0082 (9)
N60.0496 (11)0.0385 (10)0.0428 (10)0.0045 (8)0.0156 (9)−0.0022 (8)
N70.0555 (11)0.0348 (10)0.0459 (11)0.0092 (8)0.0213 (9)0.0013 (8)
N80.0395 (10)0.0408 (10)0.0347 (9)0.0067 (8)0.0108 (8)−0.0042 (8)
C10.0371 (12)0.0716 (16)0.0355 (12)0.0075 (11)−0.0017 (10)0.0006 (11)
C20.0339 (12)0.0659 (16)0.0464 (14)0.0119 (11)0.0020 (10)0.0043 (12)
C30.0387 (12)0.0557 (14)0.0305 (11)0.0088 (10)0.0063 (9)0.0039 (10)
C40.0307 (11)0.0482 (13)0.0311 (11)0.0015 (9)0.0025 (8)0.0016 (10)
C50.0348 (12)0.0593 (14)0.0284 (11)0.0038 (10)0.0051 (9)0.0005 (10)
C60.0342 (11)0.0457 (12)0.0310 (11)−0.0003 (9)0.0029 (9)0.0031 (9)
C70.0377 (12)0.0658 (15)0.0373 (12)0.0090 (11)0.0095 (10)0.0021 (11)
C80.0477 (13)0.0641 (15)0.0273 (11)0.0084 (11)0.0121 (10)−0.0004 (10)
C90.0432 (12)0.0429 (12)0.0241 (10)−0.0017 (10)0.0028 (9)0.0045 (9)
C100.0346 (11)0.0367 (11)0.0268 (10)−0.0015 (9)0.0046 (8)−0.0009 (9)
C110.0377 (11)0.0468 (13)0.0247 (10)0.0006 (9)0.0073 (9)−0.0005 (9)
C120.0466 (14)0.093 (2)0.0370 (13)0.0214 (13)0.0094 (11)0.0002 (13)
C130.0515 (13)0.0475 (14)0.0455 (13)0.0008 (11)0.0180 (11)−0.0005 (11)
C140.0483 (13)0.0517 (14)0.0449 (13)−0.0022 (11)0.0091 (11)0.0079 (11)
C150.0405 (12)0.0417 (13)0.0385 (12)0.0068 (10)0.0038 (9)−0.0016 (10)
C160.0372 (11)0.0345 (11)0.0321 (11)−0.0003 (9)0.0034 (9)−0.0055 (9)
C170.0391 (11)0.0328 (11)0.0427 (12)0.0067 (9)0.0042 (10)−0.0003 (10)
C180.0311 (10)0.0338 (11)0.0331 (11)0.0049 (8)0.0036 (8)0.0010 (9)
C190.0393 (12)0.0314 (11)0.0408 (12)0.0005 (9)0.0026 (9)0.0015 (9)
C200.0367 (11)0.0366 (12)0.0393 (12)−0.0060 (9)0.0064 (9)0.0084 (9)
C210.0345 (11)0.0398 (12)0.0307 (10)0.0001 (9)0.0071 (9)0.0009 (9)
C220.0334 (11)0.0326 (11)0.0352 (11)−0.0011 (9)0.0053 (9)−0.0004 (9)
C230.0306 (10)0.0350 (11)0.0346 (11)−0.0010 (9)0.0074 (9)0.0050 (9)
C240.0515 (14)0.0405 (13)0.0585 (15)−0.0121 (11)0.0113 (11)−0.0041 (11)
Geometric parameters (Å, °) top
O1—C91.371 (2)C6—C71.384 (3)
O1—H10.8200C6—C111.389 (3)
O2—C101.375 (2)C7—C81.379 (3)
O2—C121.421 (2)C7—H70.9300
O3—C211.344 (2)C8—C91.373 (3)
O3—H30.8200C8—H80.9300
O4—C221.379 (2)C9—C101.391 (3)
O4—C241.425 (2)C10—C111.377 (3)
N1—C31.315 (2)C11—H110.9300
N1—C21.338 (3)C12—H12A0.9600
N2—C11.333 (2)C12—H12B0.9600
N2—C41.333 (2)C12—H12C0.9600
N3—C41.355 (2)C13—C141.358 (3)
N3—N41.368 (2)C13—H130.9300
N3—H3B0.8600C14—H140.9300
N4—C51.271 (2)C15—C161.408 (3)
N5—C151.315 (3)C15—H150.9300
N5—C141.341 (3)C17—C181.456 (3)
N6—C161.332 (2)C17—H170.9300
N6—C131.342 (3)C18—C191.379 (3)
N7—C161.351 (2)C18—C231.400 (3)
N7—N81.380 (2)C19—C201.384 (3)
N7—H7A0.8600C19—H190.9300
N8—C171.270 (2)C20—C211.381 (3)
C1—C21.367 (3)C20—H200.9300
C1—H1A0.9300C21—C221.405 (3)
C2—H20.9300C22—C231.372 (3)
C3—C41.402 (3)C23—H230.9300
C3—H3A0.9300C24—H24A0.9600
C5—C61.453 (3)C24—H24B0.9600
C5—H50.9300C24—H24C0.9600
C9—O1—H1109.5C10—C11—H11119.5
C10—O2—C12116.66 (15)C6—C11—H11119.5
C21—O3—H3109.5O2—C12—H12A109.5
C22—O4—C24116.84 (15)O2—C12—H12B109.5
C3—N1—C2117.65 (17)H12A—C12—H12B109.5
C1—N2—C4116.21 (17)O2—C12—H12C109.5
C4—N3—N4120.62 (16)H12A—C12—H12C109.5
C4—N3—H3B119.7H12B—C12—H12C109.5
N4—N3—H3B119.7N6—C13—C14123.07 (19)
C5—N4—N3115.40 (16)N6—C13—H13118.5
C15—N5—C14116.28 (19)C14—C13—H13118.5
C16—N6—C13115.85 (18)N5—C14—C13121.6 (2)
C16—N7—N8119.42 (16)N5—C14—H14119.2
C16—N7—H7A120.3C13—C14—H14119.2
N8—N7—H7A120.3N5—C15—C16122.44 (19)
C17—N8—N7116.43 (17)N5—C15—H15118.8
N2—C1—C2122.9 (2)C16—C15—H15118.8
N2—C1—H1A118.5N6—C16—N7116.79 (18)
C2—C1—H1A118.5N6—C16—C15120.69 (18)
N1—C2—C1120.71 (19)N7—C16—C15122.47 (17)
N1—C2—H2119.6N8—C17—C18122.33 (18)
C1—C2—H2119.6N8—C17—H17118.8
N1—C3—C4121.36 (19)C18—C17—H17118.8
N1—C3—H3A119.3C19—C18—C23118.48 (17)
C4—C3—H3A119.3C19—C18—C17120.55 (18)
N2—C4—N3115.78 (17)C23—C18—C17120.96 (17)
N2—C4—C3121.12 (18)C18—C19—C20121.13 (18)
N3—C4—C3123.09 (18)C18—C19—H19119.4
N4—C5—C6123.47 (18)C20—C19—H19119.4
N4—C5—H5118.3C21—C20—C19120.69 (18)
C6—C5—H5118.3C21—C20—H20119.7
C7—C6—C11118.67 (18)C19—C20—H20119.7
C7—C6—C5123.47 (18)O3—C21—C20124.72 (17)
C11—C6—C5117.86 (17)O3—C21—C22116.88 (17)
C8—C7—C6120.58 (19)C20—C21—C22118.39 (17)
C8—C7—H7119.7C23—C22—O4124.72 (17)
C6—C7—H7119.7C23—C22—C21120.75 (18)
C9—C8—C7120.39 (18)O4—C22—C21114.52 (16)
C9—C8—H8119.8C22—C23—C18120.54 (17)
C7—C8—H8119.8C22—C23—H23119.7
O1—C9—C8119.17 (17)C18—C23—H23119.7
O1—C9—C10120.96 (18)O4—C24—H24A109.5
C8—C9—C10119.87 (18)O4—C24—H24B109.5
O2—C10—C11125.68 (16)H24A—C24—H24B109.5
O2—C10—C9114.90 (16)O4—C24—H24C109.5
C11—C10—C9119.42 (18)H24A—C24—H24C109.5
C10—C11—C6121.07 (17)H24B—C24—H24C109.5
C4—N3—N4—C5178.2 (2)C5—C6—C11—C10−178.98 (18)
C16—N7—N8—C17−169.45 (19)C16—N6—C13—C14−0.2 (3)
C4—N2—C1—C20.0 (3)C15—N5—C14—C13−0.4 (3)
C3—N1—C2—C1−0.5 (3)N6—C13—C14—N50.9 (4)
N2—C1—C2—N10.4 (4)C14—N5—C15—C16−0.7 (3)
C2—N1—C3—C40.1 (3)C13—N6—C16—N7−178.42 (19)
C1—N2—C4—N3−179.34 (19)C13—N6—C16—C15−0.9 (3)
C1—N2—C4—C3−0.4 (3)N8—N7—C16—N6−168.35 (17)
N4—N3—C4—N2−172.90 (19)N8—N7—C16—C1514.2 (3)
N4—N3—C4—C38.1 (3)N5—C15—C16—N61.4 (3)
N1—C3—C4—N20.3 (3)N5—C15—C16—N7178.8 (2)
N1—C3—C4—N3179.2 (2)N7—N8—C17—C18−174.17 (17)
N3—N4—C5—C6−178.85 (19)N8—C17—C18—C19−164.76 (19)
N4—C5—C6—C7−5.5 (3)N8—C17—C18—C2316.5 (3)
N4—C5—C6—C11174.3 (2)C23—C18—C19—C20−1.4 (3)
C11—C6—C7—C8−0.7 (3)C17—C18—C19—C20179.80 (18)
C5—C6—C7—C8179.1 (2)C18—C19—C20—C210.5 (3)
C6—C7—C8—C9−0.2 (3)C19—C20—C21—O3−178.01 (19)
C7—C8—C9—O1−179.9 (2)C19—C20—C21—C220.8 (3)
C7—C8—C9—C100.9 (3)C24—O4—C22—C2316.6 (3)
C12—O2—C10—C11−0.7 (3)C24—O4—C22—C21−164.40 (18)
C12—O2—C10—C9179.54 (19)O3—C21—C22—C23177.75 (18)
O1—C9—C10—O2−0.1 (3)C20—C21—C22—C23−1.2 (3)
C8—C9—C10—O2179.09 (18)O3—C21—C22—O4−1.3 (3)
O1—C9—C10—C11−179.95 (18)C20—C21—C22—O4179.83 (17)
C8—C9—C10—C11−0.7 (3)O4—C22—C23—C18179.11 (18)
O2—C10—C11—C6−179.95 (18)C21—C22—C23—C180.2 (3)
C9—C10—C11—C6−0.1 (3)C19—C18—C23—C221.1 (3)
C7—C6—C11—C100.9 (3)C17—C18—C23—C22179.84 (18)
Table 1
Selected geometric parameters (Å, °) top
O1—H10.8200N7—N81.380 (2)
N3—N41.368 (2)N8—C171.270 (2)
N4—C51.271 (2)
C10—O2—C12116.66 (15)O1—C9—C10120.96 (18)
C22—O4—C24116.84 (15)O2—C10—C11125.68 (16)
C4—N3—N4120.62 (16)O2—C10—C9114.90 (16)
C5—N4—N3115.40 (16)N8—C17—C18122.33 (18)
C16—N7—N8119.42 (16)O3—C21—C20124.72 (17)
C17—N8—N7116.43 (17)O3—C21—C22116.88 (17)
N4—C5—C6123.47 (18)C23—C22—O4124.72 (17)
O1—C9—C8119.17 (17)O4—C22—C21114.52 (16)
Table 2
Table 1. Hydrogen-bond geometry (Å, °). top
D-H···AD-HH···AD···AD-H···A
O1-H1···O20.822.232.677 (2)115
O1-H1···O4ii0.822.242.993 (2)152
O3-H3···N1iii0.821.932.736 (2)165
N3-H3B···N2iv0.862.253.060 (2)157
N7-H7A···N6v0.862.233.044 (2)159
Symmetry codes: (ii) 1 - x, -y, 1 - z; (iii) 1 + x, 1 - y, 1/2 + z; (iv) -x, y, -z - 1/2; (v) 3/2 - x, 3/2 - y, 2 - z
references
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