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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 5| May 2011| Page o1135

Pyridine-4-carbaldehyde 4-phenylsemicarbazone

aDepartamento de Química Física y Analítica, Facultad de Química, Universidad de Oviedo - CINN, C/ Julián Clavería, 8, 33006 Oviedo, Spain
*Correspondence e-mail: sgg@uniovi.es

(Received 29 March 2011; accepted 7 April 2011; online 16 April 2011)

In the title compound, C13H12N4O, the semicarbazone fragment links a benzene and a pyridine ring in the structure. The crystal packing is stabilized by strong inter­molecular N—H⋯O hydrogen bonds, which connect two mol­ecules to form a synthon unit, and by N—H⋯N hydrogen bonds and weak C—H⋯π inter­actions. The mol­ecular conformation is stabil­ized by intra­molecular N—H⋯N and C—H⋯O inter­actions.

Related literature

For related compounds and their biological activity, see: Pavan et al. (2010[Pavan, R. F., Maia, P. S., Leite, S., Deflon, V. M. & Batista, A. (2010). Eur. J. Med. Chem. 45,1898-1905.]); Yogeeswari et al. (2005[Yogeeswari, P., Sriram, D., Veena, V., Kavya, R., Rakhra, K., Ragavendran, J., Mehta, S., Thirumurugan, R. & Stables, J. P. (2005). Biomed. Pharmacother. 59, 51-55.]).

[Scheme 1]

Experimental

Crystal data
  • C13H12N4O

  • Mr = 240.27

  • Monoclinic, P 21 /c

  • a = 9.2794 (6) Å

  • b = 10.3384 (8) Å

  • c = 12.8244 (8) Å

  • β = 100.744 (6)°

  • V = 1208.73 (15) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 0.72 mm−1

  • T = 295 K

  • 0.30 × 0.11 × 0.06 mm

Data collection
  • Oxford Diffraction Xcalibur Gemini R diffractometer

  • Absorption correction: multi-scan (ABSPACK in CrysAlis PRO; Oxford Diffraction, 2010[Oxford Diffraction (2010). CrysAlis CCD, CrysAlis RED and CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.]) Tmin = 0.888, Tmax = 1.000

  • 7257 measured reflections

  • 2310 independent reflections

  • 1702 reflections with I > 2σ(I)

  • Rint = 0.066

Refinement
  • R[F2 > 2σ(F2)] = 0.052

  • wR(F2) = 0.143

  • S = 1.06

  • 2310 reflections

  • 176 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.20 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of the C8–C13 ring.

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H3N⋯O1i 0.93 (2) 1.91 (2) 2.833 (2) 172 (2)
N4—H4N⋯N1ii 0.91 (2) 2.24 (2) 3.122 (3) 161.8 (19)
N4—H4N⋯N2 0.91 (2) 2.29 (2) 2.685 (2) 105.4 (16)
C13—H13⋯O1 0.93 2.31 2.854 (2) 117
C1—H1⋯Cg2iii 0.93 2.88 3.644 (2) 140
Symmetry codes: (i) -x+1, -y, -z+2; (ii) -x+1, -y, -z+1; (iii) x+1, y, z.

Data collection: CrysAlis CCD (Oxford Diffraction, 2010[Oxford Diffraction (2010). CrysAlis CCD, CrysAlis RED and CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2010[Oxford Diffraction (2010). CrysAlis CCD, CrysAlis RED and CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.]); data reduction: CrysAlis RED; program(s) used to solve structure: SIR92 (Altomare et al., 1994[Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.]); 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, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: WinGX publication routines (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]), PLATON (Spek, 2009)[Spek, A. L. (2009). Acta Cryst. D65, 148-155.] and PARST95 (Nardelli, 1995[Nardelli, M. (1995). J. Appl. Cryst. 28, 659.]).

Supporting information


Comment top

Semicarbazones and their metal complexes are important classes of compounds which have long attracted attention owing to their remarkable biological and pharmacological properties, such as antibacterial, antiviral, antineoplastic and anti Mycobacterium tuberculosis activity (Pavan et al., 2010). Using the semicarbazone template (Yogeeswari et al., 2005), significant anticonvulsant potential was demonstrated in epilepsy models for aryl semicarbazones. In view of the importance of these compounds, a new semicarbazone (I) has been synthesized, and its crystal structure is reported here (Fig. 1).

The configuration of (I) is E with respect to the C6N2 bond. The pyridine and benzene rings are conected by a semicarbazone fragment (C6/N2/N3/C7/O1/N4). The values of the dihedral angles between the aromatic rings and the semicarbazone fragnent are 23.99 (7)° and 42.15 (7)° for the benzene and pyridine rings, respectively. This indicates the lack of planarity.

The crystal packing is stabilized by a pair of strong intermolecular N—H···O hydrogen bonds conecting two molecules to form a centrosymmtric unit (synthon), and by an N—H···N hydrogen bond (Fig. 2), which extends the packing along the c axis (Fig 3). The crystal is also stabilized by intermolecular C—H···π interactions (Fig. 4). This type of interaction affects the conformation of the molecule, specifically the torsion angle between the benzene ring and the semicarbazone moeity. The molecular conformation is stabilized by intramolecular N4—H4N···N2 and C13—H13···O1 interactions (Table 1).

From the centroid–centroid distance between two pyridine rings [4.0085 (2)Å] and the angle between the normal of the aromatic plane and the centroid–centroid vector [35.13 (5)°], we conclude that there is no significant π-π stacking interaction between the pyridine rings.

Related literature top

For related compounds and their biological activity, see: Pavan et al. (2010); Yogeeswari et al. (2005).

Experimental top

A solution of 4-pyridine carboxaldehyde (1.0711 g, 0.01 mol) and 4-phenylsemicarbazide (1.5117 g, 0.01 mol) in absolute methanol (50 ml) was refluxed for 4 h in the presence of p-toluenesulfonic acid as catalyst, with continuous stirring. On cooling to room temperature the precipitate was filtered off, washed with copious cold methanol and dried in air (m.p. 493.15 K). White single crystals of compound (I) were obtained after recrystallization from a solution in methanol.

Refinement top

The NH and Schiff base CH H-atoms were found in difference Fourier maps and were freely refined: N3—H = 0.93 (2) Å, N4—H = 0.91 (2) Å and C6—H=0.99 (2) Å. All other C-bound H-atoms were included in calculated positions and treated as riding atoms: C—H = 0.93 Å for aromatic CH with Uiso(H) = 1.2 × Ueq(C). At the end of the refinement the highest peak in the electron density was 0.20 eÅ -3, while the deepest hole was -0.17 eÅ -3.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2010); cell refinement: CrysAlis RED (Oxford Diffraction, 2010); data reduction: CrysAlis RED (Oxford Diffraction, 2010); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2008); software used to prepare material for publication: WinGX publication routines (Farrugia, 1999), PLATON (Spek, 2009) and PARST95 (Nardelli, 1995).

Figures top
[Figure 1] Fig. 1. A view of the molecular structure of the title molecule showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Part of the crystal packing showing the principal intermolecular and intramolecular hydrogen bonds. Displacement ellipsoids are drawn at the 50% probability level. H atoms not involved in hydrogen bonding have been omitted for clarity.
[Figure 3] Fig. 3. Packing diagram viewed along the c axis. Hydrogen bonds are indicated by dashed lines.
[Figure 4] Fig. 4. Intermolecular C—H···π interactions along ac plane. H atoms not involved in hydrogen bonding have been omitted for clarity.
Pyridine-4-carbaldehyde 4-phenylsemicarbazone top
Crystal data top
C13H12N4OF(000) = 504
Mr = 240.27Dx = 1.320 Mg m3
Monoclinic, P21/cMelting point: 493.15 K
Hall symbol: -P 2ybcCu Kα radiation, λ = 1.54180 Å
a = 9.2794 (6) ÅCell parameters from 2114 reflections
b = 10.3384 (8) Åθ = 3.5–70.7°
c = 12.8244 (8) ŵ = 0.72 mm1
β = 100.744 (6)°T = 295 K
V = 1208.73 (15) Å3Rod, white
Z = 40.30 × 0.11 × 0.06 mm
Data collection top
Oxford Diffraction Xcalibur Gemini R
diffractometer
2310 independent reflections
Radiation source: Enhance (Cu) X-ray Source1702 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.066
Detector resolution: 10.2673 pixels mm-1θmax = 70.8°, θmin = 4.9°
ω scansh = 1011
Absorption correction: multi-scan
(ABSPACK in CrysAlis PRO; Oxford Diffraction, 2010)
k = 1211
Tmin = 0.888, Tmax = 1.000l = 1515
7257 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.052H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.143 w = 1/[σ2(Fo2) + (0.0648P)2 + 0.0647P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max < 0.001
2310 reflectionsΔρmax = 0.20 e Å3
176 parametersΔρmin = 0.17 e Å3
0 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0051 (8)
Crystal data top
C13H12N4OV = 1208.73 (15) Å3
Mr = 240.27Z = 4
Monoclinic, P21/cCu Kα radiation
a = 9.2794 (6) ŵ = 0.72 mm1
b = 10.3384 (8) ÅT = 295 K
c = 12.8244 (8) Å0.30 × 0.11 × 0.06 mm
β = 100.744 (6)°
Data collection top
Oxford Diffraction Xcalibur Gemini R
diffractometer
2310 independent reflections
Absorption correction: multi-scan
(ABSPACK in CrysAlis PRO; Oxford Diffraction, 2010)
1702 reflections with I > 2σ(I)
Tmin = 0.888, Tmax = 1.000Rint = 0.066
7257 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0520 restraints
wR(F2) = 0.143H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.20 e Å3
2310 reflectionsΔρmin = 0.17 e Å3
176 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
O10.31018 (14)0.04113 (16)0.96710 (10)0.0562 (4)
N20.47959 (17)0.03751 (17)0.75432 (12)0.0474 (4)
N30.45910 (18)0.01377 (19)0.85540 (13)0.0524 (5)
N40.23363 (17)0.07764 (18)0.78923 (13)0.0478 (4)
N10.7010 (2)0.1407 (2)0.43544 (14)0.0619 (5)
C70.3301 (2)0.0358 (2)0.87508 (14)0.0443 (5)
C40.5324 (2)0.1475 (2)0.55575 (16)0.0505 (5)
H40.43830.16660.56650.061*
C30.5689 (2)0.1643 (2)0.45723 (16)0.0557 (5)
H30.49640.19400.40240.067*
C80.0926 (2)0.1288 (2)0.79070 (15)0.0467 (5)
C50.6378 (2)0.1016 (2)0.63847 (15)0.0466 (5)
C90.0279 (2)0.2034 (2)0.70528 (16)0.0551 (5)
H90.07820.21930.65020.066*
C60.6074 (2)0.0739 (2)0.74389 (16)0.0489 (5)
C130.0161 (2)0.1054 (2)0.87145 (16)0.0575 (6)
H130.05720.05410.92890.069*
C100.1102 (3)0.2545 (3)0.70086 (19)0.0672 (7)
H100.15280.30380.64250.081*
C20.8014 (2)0.0989 (3)0.51620 (18)0.0657 (6)
H20.89490.08170.50340.079*
C10.7765 (2)0.0794 (2)0.61736 (17)0.0571 (6)
H10.85190.05160.67090.069*
C120.1218 (2)0.1586 (3)0.86654 (19)0.0687 (7)
H120.17220.14340.92160.082*
C110.1858 (3)0.2335 (3)0.7820 (2)0.0712 (7)
H110.27830.26920.77960.085*
H60.686 (2)0.083 (2)0.8069 (17)0.058 (6)*
H3N0.533 (3)0.031 (2)0.9132 (19)0.065 (7)*
H4N0.266 (2)0.080 (2)0.7265 (18)0.053 (6)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0482 (8)0.0824 (11)0.0385 (7)0.0050 (7)0.0096 (6)0.0017 (7)
N20.0489 (9)0.0571 (10)0.0367 (8)0.0029 (7)0.0089 (7)0.0020 (7)
N30.0444 (9)0.0765 (13)0.0358 (8)0.0107 (8)0.0066 (7)0.0017 (8)
N40.0439 (9)0.0619 (11)0.0388 (8)0.0066 (7)0.0110 (7)0.0011 (7)
N10.0681 (12)0.0707 (13)0.0507 (10)0.0103 (9)0.0212 (9)0.0032 (9)
C70.0430 (10)0.0525 (12)0.0373 (10)0.0012 (8)0.0076 (7)0.0035 (8)
C40.0517 (11)0.0529 (12)0.0482 (11)0.0021 (9)0.0124 (9)0.0005 (9)
C30.0614 (13)0.0577 (14)0.0473 (12)0.0047 (10)0.0081 (9)0.0026 (9)
C80.0447 (10)0.0521 (12)0.0437 (10)0.0019 (8)0.0092 (8)0.0038 (8)
C50.0484 (10)0.0497 (12)0.0423 (10)0.0084 (8)0.0103 (8)0.0044 (8)
C90.0580 (12)0.0613 (14)0.0472 (11)0.0101 (10)0.0127 (9)0.0036 (10)
C60.0430 (10)0.0603 (13)0.0428 (10)0.0061 (9)0.0065 (8)0.0024 (9)
C130.0521 (11)0.0751 (16)0.0479 (11)0.0077 (10)0.0159 (9)0.0106 (10)
C100.0679 (14)0.0759 (17)0.0579 (14)0.0233 (11)0.0116 (11)0.0102 (11)
C20.0568 (13)0.0857 (18)0.0597 (13)0.0021 (11)0.0239 (11)0.0007 (12)
C10.0464 (11)0.0726 (15)0.0530 (12)0.0040 (10)0.0105 (9)0.0012 (10)
C120.0568 (13)0.0924 (19)0.0611 (14)0.0139 (12)0.0219 (10)0.0058 (13)
C110.0586 (14)0.0851 (19)0.0725 (16)0.0239 (12)0.0193 (12)0.0045 (13)
Geometric parameters (Å, º) top
O1—C71.229 (2)C8—C91.382 (3)
N2—C61.275 (2)C5—C11.383 (3)
N2—N31.367 (2)C5—C61.460 (3)
N3—N21.367 (2)C9—C101.378 (3)
N3—C71.368 (2)C9—H90.9300
N3—H3N0.93 (2)C6—H60.99 (2)
N4—C71.354 (2)C13—C121.384 (3)
N4—C81.415 (2)C13—H130.9300
N4—H4N0.91 (2)C10—C111.376 (3)
N1—C31.329 (3)C10—H100.9300
N1—C21.329 (3)C2—C11.374 (3)
C4—C31.379 (3)C2—H20.9300
C4—C51.386 (3)C1—H10.9300
C4—H40.9300C12—C111.373 (3)
C3—H30.9300C12—H120.9300
C8—C131.381 (3)C11—H110.9300
C6—N2—N3116.68 (16)C10—C9—H9119.7
N2—N3—C7121.56 (16)C8—C9—H9119.7
N2—N3—H3N120.5 (14)N2—C6—C5119.94 (17)
C7—N3—H3N117.9 (14)N2—C6—H6120.3 (12)
C7—N4—C8125.56 (16)C5—C6—H6119.8 (12)
C7—N4—H4N116.7 (13)C8—C13—C12119.8 (2)
C8—N4—H4N117.4 (13)C8—C13—H13120.1
C3—N1—C2115.80 (18)C12—C13—H13120.1
O1—C7—N4124.85 (17)C11—C10—C9120.6 (2)
O1—C7—N3119.15 (17)C11—C10—H10119.7
N4—C7—N3115.99 (16)C9—C10—H10119.7
C3—C4—C5119.03 (19)N1—C2—C1124.5 (2)
C3—C4—H4120.5N1—C2—H2117.7
N1—C3—C4124.3 (2)C1—C2—H2117.7
N1—C3—H3117.9C2—C1—C5119.1 (2)
C4—C3—H3117.9C2—C1—H1120.4
C13—C8—C9118.96 (18)C5—C1—H1120.4
C13—C8—N4123.37 (18)C11—C12—C13121.3 (2)
C9—C8—N4117.65 (18)C11—C12—H12119.3
C1—C5—C4117.19 (18)C13—C12—H12119.3
C1—C5—C6119.74 (18)C12—C11—C10118.7 (2)
C4—C5—C6123.05 (18)C12—C11—H11120.7
C10—C9—C8120.6 (2)C10—C11—H11120.7
C6—N2—N3—C7174.5 (2)N3—N2—C6—C5179.75 (18)
C8—N4—C7—O12.8 (3)C1—C5—C6—N2148.6 (2)
C8—N4—C7—N3178.13 (19)C4—C5—C6—N230.0 (3)
N2—N3—C7—O1171.39 (19)C9—C8—C13—C121.2 (3)
N2—N3—C7—N49.5 (3)N4—C8—C13—C12179.6 (2)
C2—N1—C3—C40.3 (3)C8—C9—C10—C110.7 (4)
C5—C4—C3—N10.8 (3)C3—N1—C2—C10.1 (4)
C7—N4—C8—C1321.7 (3)N1—C2—C1—C51.3 (4)
C7—N4—C8—C9159.8 (2)C4—C5—C1—C22.3 (3)
C3—C4—C5—C12.1 (3)C6—C5—C1—C2176.3 (2)
C3—C4—C5—C6176.49 (19)C8—C13—C12—C110.8 (4)
C13—C8—C9—C100.4 (3)C13—C12—C11—C100.3 (4)
N4—C8—C9—C10179.0 (2)C9—C10—C11—C121.1 (4)
Hydrogen-bond geometry (Å, º) top
Cg2 is the centroid of the C8–C13 ring.
D—H···AD—HH···AD···AD—H···A
N3—H3N···O1i0.93 (2)1.91 (2)2.833 (2)172 (2)
N4—H4N···N1ii0.91 (2)2.24 (2)3.122 (3)161.8 (19)
N4—H4N···N20.91 (2)2.29 (2)2.685 (2)105.4 (16)
C13—H13···O10.932.312.854 (2)117
C1—H1···Cg2iii0.932.883.644 (2)140
Symmetry codes: (i) x+1, y, z+2; (ii) x+1, y, z+1; (iii) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC13H12N4O
Mr240.27
Crystal system, space groupMonoclinic, P21/c
Temperature (K)295
a, b, c (Å)9.2794 (6), 10.3384 (8), 12.8244 (8)
β (°) 100.744 (6)
V3)1208.73 (15)
Z4
Radiation typeCu Kα
µ (mm1)0.72
Crystal size (mm)0.30 × 0.11 × 0.06
Data collection
DiffractometerOxford Diffraction Xcalibur Gemini R
diffractometer
Absorption correctionMulti-scan
(ABSPACK in CrysAlis PRO; Oxford Diffraction, 2010)
Tmin, Tmax0.888, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
7257, 2310, 1702
Rint0.066
(sin θ/λ)max1)0.613
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.052, 0.143, 1.06
No. of reflections2310
No. of parameters176
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.20, 0.17

Computer programs: CrysAlis CCD (Oxford Diffraction, 2010), CrysAlis RED (Oxford Diffraction, 2010), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2008), WinGX publication routines (Farrugia, 1999), PLATON (Spek, 2009) and PARST95 (Nardelli, 1995).

Hydrogen-bond geometry (Å, º) top
Cg2 is the centroid of the C8–C13 ring.
D—H···AD—HH···AD···AD—H···A
N3—H3N···O1i0.93 (2)1.91 (2)2.833 (2)172 (2)
N4—H4N···N1ii0.91 (2)2.24 (2)3.122 (3)161.8 (19)
N4—H4N···N20.91 (2)2.29 (2)2.685 (2)105.4 (16)
C13—H13···O10.932.312.854 (2)117
C1—H1···Cg2iii0.932.883.644 (2)140
Symmetry codes: (i) x+1, y, z+2; (ii) x+1, y, z+1; (iii) x+1, y, z.
 

Acknowledgements

Financial support by the Agencia Española de Cooperación Inter­nacional y Desarrollo (AECID), FEDER funding, the Spanish MICINN (MAT2006–01997, MAT2010-15094 and the Factoría de Cristalización Consolider Ingenio 2010), the Gobierno del Principado de Asturias (PCTI), the University of Oviedo and Banco Santander is acknowledged.

References

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Volume 67| Part 5| May 2011| Page o1135
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