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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 66| Part 6| June 2010| Page o1303
https://doi.org/10.1107/S1600536810016417

4-Formyl-3-p-tolyl­sydnone

Jia Hao Goh,a‡ Hoong-Kun Fun,a*§ Nithinchandrab and B. Kallurayab

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri, Mangalore 574 199, India
*Correspondence e-mail: hkfun@usm.my

(Received 7 April 2010; accepted 5 May 2010; online 8 May 2010)

In the title compound, C10H8N2O3, the oxadiazole ring is essentially planar, with a maximum deviation of 0.006 (1) Å for the two-connected N atom. The mean planes through the aldehyde unit and the methyl-substituted phenyl ring make inter­planar angles of 13.60 (9) and 59.69 (4)°, respectively, with the oxadiazole ring. In the crystal structure, adjacent mol­ecules are inter­connected into a two-dimensional array parallel to (100) by inter­molecular C—H⋯O hydrogen bonds.

Related literature

For general background to and applications of sydnone compounds, see: Hedge et al. (2008[Hedge, J. C., Girisha, K. S., Adhikari, A. & Kalluraya, B. (2008). Eur. J. Med. Chem. 43, 2831-2834.]); Rai et al. (2008[Rai, N. S., Kalluraya, B., Lingappa, B., Shenoy, S. & Puranic, V. G. (2008). Eur. J. Med. Chem. 43, 1715-1720.]). For related sydnone structures, see: Baker & Ollis (1957[Baker, W. & Ollis, W. D. (1957). Q. Rev. Chem. Soc. 11, 15-29.]); Grossie et al. (2009[Grossie, D. A., Turnbull, K., Felix-Balderrama, S. & Raghavapuram, S. (2009). Acta Cryst. E65, o554-o555.]). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data

  • C10H8N2O3

  • Mr = 204.18

  • Monoclinic, P 21 /c

  • a = 10.5663 (4) Å

  • b = 10.4088 (3) Å

  • c = 8.9630 (3) Å

  • β = 108.222 (1)°

  • V = 936.34 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 100 K

  • 0.71 × 0.30 × 0.19 mm
Data collection

  • Bruker APEXII DUO CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.926, Tmax = 0.980

  • 14437 measured reflections

  • 4906 independent reflections

  • 4091 reflections with I > 2σ(I)

  • Rint = 0.022
Refinement

  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.132

  • S = 1.07

  • 4906 reflections

  • 137 parameters

  • H-atom parameters constrained

  • Δρmax = 0.65 e Å−3

  • Δρmin = −0.31 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C1—H1A⋯O2i 0.93 2.41 3.2847 (9) 156
C5—H5A⋯O3ii 0.93 2.60 3.3489 (11) 138
Symmetry codes: (i) -x+1, -y+1, -z+2; (ii) [-x+1, y-{\script{1\over 2}}, -z+{\script{5\over 2}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810016417/fj2294sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810016417/fj2294Isup2.hkl

checkCIF report


Comment top

Sydnones constitute a well-defined class of mesoionic compounds consisting of 1,2,3-oxadiazole ring system. The introduction of the concept of mesoionic structure for certain heterocyclic compounds in the year 1949 has proved to be fruitful development in heterocyclic chemistry. The study of sydnones still remains a field of interest because of their electronic structure and also because of the various types of biological activities displayed by some of them. Interest in sydnone derivatives has also been encouraged by the discovery that they exhibit various pharmacological activities (Hedge et al., 2008; Rai et al., 2008).

These 4-formyl sydnone will be used for the preparation of a new series of α,β-unsaturated carbonyl compounds (namely chalcones) by condensation with appropriate ketones or aldehydes. These α,β-unsaturated carbonyl compounds will be utilized for the synthesis of a variety of novel heterocyclic compounds like pyrazolines, pyrazole etc carrying sydnone moiety.

Sydnones are mesoionic compounds containing a five-membered heterocyclic ring. Generally, substitution at the N3 position by an aromatic substituent is necessary for stability. In the title sydnone compound (Fig. 1), the aromatic substituent is p-toluene. The 1,2,3-oxadiazole ring (N1/N2/O1/C7/C8) in the sydnone unit is essentially planar, with maximum deviation of -0.006 (1) Å at atom N2. The mean planes through the aldehyde moiety (C9/H9A/O3) and methyl-substituted phenyl ring (C1-C6) are inclined at dihedral angles of 13.60 (9) and 59.69 (4)°, respectively, with the 1,2,3-oxadiazole ring. As reported previously (Grossie et al., 2009), the exocyclic C7–O2 bond length of 1.2089 (9) Å is inconsistent to the formulation of Baker & Ollis (1957), which reported the delocalization of a positive charge in the ring, and a negative charge in the exocyclic oxygen. The bond lengths (Allen et al., 1987) and angles are within normal range and comparable to a related sydnone structure (Grossie et al., 2009). In the crystal structure (Fig. 2), intermolecular C1—H1A···O2 and C5—H5A···O3 hydrogen bonds (Table 1) link adjacent molecules into two-dimensional arrays parallel to the (100) plane.

Related literature top

For general background to and applications of sydnone compounds, see: Hedge et al. (2008); Rai et al. (2008). For related sydnone structures, see: Baker & Ollis (1957); Grossie et al. (2009). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986). For bond-length data, see: Allen et al. (1987).

Experimental top

N-Methylformanilide (0.01 mol) and phosphoryl chloride (0.01 mol) were mixed and added into 3-(p-tolyl)sydnone (0.01 mol) portion-wise. The reaction mixture was then stirred for about 1 h under cold condition. After standing overnight, it was poured into ice cold water with stirring. The solid obtained was filtered, dried and recrystallized from ethanol. Single crystals suitable for X-ray analysis were obtained from a 1:2 mixture of DMF and ethanol by slow evaporation.

Refinement top

All hydrogen atoms were placed in their calculated positions, with C—H = 0.93 or 0.96 Å, and refined using a riding model with Uiso = 1.2 or 1.5 Ueq(C). A rotating group model was used for the C10 methyl group.

Structure description top

Sydnones constitute a well-defined class of mesoionic compounds consisting of 1,2,3-oxadiazole ring system. The introduction of the concept of mesoionic structure for certain heterocyclic compounds in the year 1949 has proved to be fruitful development in heterocyclic chemistry. The study of sydnones still remains a field of interest because of their electronic structure and also because of the various types of biological activities displayed by some of them. Interest in sydnone derivatives has also been encouraged by the discovery that they exhibit various pharmacological activities (Hedge et al., 2008; Rai et al., 2008).

These 4-formyl sydnone will be used for the preparation of a new series of α,β-unsaturated carbonyl compounds (namely chalcones) by condensation with appropriate ketones or aldehydes. These α,β-unsaturated carbonyl compounds will be utilized for the synthesis of a variety of novel heterocyclic compounds like pyrazolines, pyrazole etc carrying sydnone moiety.

Sydnones are mesoionic compounds containing a five-membered heterocyclic ring. Generally, substitution at the N3 position by an aromatic substituent is necessary for stability. In the title sydnone compound (Fig. 1), the aromatic substituent is p-toluene. The 1,2,3-oxadiazole ring (N1/N2/O1/C7/C8) in the sydnone unit is essentially planar, with maximum deviation of -0.006 (1) Å at atom N2. The mean planes through the aldehyde moiety (C9/H9A/O3) and methyl-substituted phenyl ring (C1-C6) are inclined at dihedral angles of 13.60 (9) and 59.69 (4)°, respectively, with the 1,2,3-oxadiazole ring. As reported previously (Grossie et al., 2009), the exocyclic C7–O2 bond length of 1.2089 (9) Å is inconsistent to the formulation of Baker & Ollis (1957), which reported the delocalization of a positive charge in the ring, and a negative charge in the exocyclic oxygen. The bond lengths (Allen et al., 1987) and angles are within normal range and comparable to a related sydnone structure (Grossie et al., 2009). In the crystal structure (Fig. 2), intermolecular C1—H1A···O2 and C5—H5A···O3 hydrogen bonds (Table 1) link adjacent molecules into two-dimensional arrays parallel to the (100) plane.

For general background to and applications of sydnone compounds, see: Hedge et al. (2008); Rai et al. (2008). For related sydnone structures, see: Baker & Ollis (1957); Grossie et al. (2009). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986). For bond-length data, see: Allen et al. (1987).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids for non-H atoms and the atom-numbering scheme.
[Figure 2] Fig. 2. The crystal structure of the title compound, viewed along the a axis, showing a two-dimensional array parallel to the (100) plane. Hydrogen atoms not involved in intermolecular interactions (dashed lines) have been omitted for clarity.
4-Formyl-3-p-tolylsydnone top
Crystal data top
C10H8N2O3F(000) = 424
Mr = 204.18Dx = 1.448 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 6788 reflections
a = 10.5663 (4) Åθ = 2.8–38.9°
b = 10.4088 (3) ŵ = 0.11 mm−1
c = 8.9630 (3) ÅT = 100 K
β = 108.222 (1)°Block, brown
V = 936.34 (5) Å30.71 × 0.30 × 0.19 mm
Z = 4
Data collection top
Bruker APEXII DUO CCD area-detector
diffractometer		4906 independent reflections
Radiation source: fine-focus sealed tube4091 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.022
φ and ω scansθmax = 37.5°, θmin = 2.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)		h = −18→18
Tmin = 0.926, Tmax = 0.980k = −17→17
14437 measured reflectionsl = −15→14
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) = 0.132H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0747P)2 + 0.1421P]
where P = (Fo2 + 2Fc2)/3
4906 reflections(Δ/σ)max = 0.001
137 parametersΔρmax = 0.65 e Å−3
0 restraintsΔρmin = −0.31 e Å−3
Crystal data top
C10H8N2O3V = 936.34 (5) Å3
Mr = 204.18Z = 4
Monoclinic, P21/cMo Kα radiation
a = 10.5663 (4) ŵ = 0.11 mm−1
b = 10.4088 (3) ÅT = 100 K
c = 8.9630 (3) Å0.71 × 0.30 × 0.19 mm
β = 108.222 (1)°
Data collection top
Bruker APEXII DUO CCD area-detector
diffractometer		4906 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)		4091 reflections with I > 2σ(I)
Tmin = 0.926, Tmax = 0.980Rint = 0.022
14437 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0420 restraints
wR(F2) = 0.132H-atom parameters constrained
S = 1.07Δρmax = 0.65 e Å−3
4906 reflectionsΔρmin = −0.31 e Å−3
137 parameters
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1)K.

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
O10.34006 (6)0.22147 (5)0.96639 (6)0.01912 (11)
O20.26550 (6)0.39559 (5)1.06918 (7)0.02245 (12)
O30.53489 (6)0.55203 (5)1.23353 (7)0.02190 (12)
N10.54958 (6)0.24689 (5)1.05402 (6)0.01524 (10)
N20.45929 (7)0.17063 (6)0.96707 (7)0.01825 (11)
C10.76823 (8)0.30000 (7)1.03217 (9)0.02080 (13)
H1A0.73460.37730.98390.025*
C20.90126 (8)0.26687 (7)1.05976 (10)0.02297 (14)
H2A0.95710.32281.02890.028*
C30.95243 (8)0.15115 (7)1.13297 (9)0.02082 (13)
C40.86671 (8)0.06713 (7)1.17625 (9)0.02117 (13)
H4A0.8996−0.01061.22380.025*
C50.73342 (8)0.09745 (6)1.14961 (8)0.01803 (12)
H5A0.67680.04111.17830.022*
C60.68736 (7)0.21424 (6)1.07890 (7)0.01561 (11)
C70.35989 (7)0.33640 (6)1.05605 (8)0.01719 (12)
C80.50088 (7)0.34990 (6)1.11215 (8)0.01566 (11)
C90.58136 (8)0.44999 (6)1.20780 (8)0.01744 (12)
H9A0.67240.43621.25170.021*
C101.09685 (9)0.11710 (10)1.16471 (12)0.03014 (17)
H10D1.14600.19281.15620.045*
H10A1.10480.05451.08950.045*
H10B1.13190.08231.26870.045*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0194 (2)0.0159 (2)0.0216 (2)0.00027 (17)0.00558 (19)−0.00320 (16)
O20.0212 (3)0.0188 (2)0.0285 (3)0.00347 (18)0.0094 (2)−0.00196 (18)
O30.0306 (3)0.0144 (2)0.0250 (2)−0.00230 (19)0.0148 (2)−0.00363 (17)
N10.0194 (3)0.01228 (19)0.0155 (2)−0.00027 (17)0.00755 (19)−0.00047 (15)
N20.0206 (3)0.0153 (2)0.0194 (2)−0.00021 (19)0.0070 (2)−0.00313 (17)
C10.0255 (3)0.0152 (2)0.0263 (3)−0.0009 (2)0.0148 (3)0.0028 (2)
C20.0243 (3)0.0202 (3)0.0294 (3)−0.0039 (2)0.0157 (3)−0.0007 (2)
C30.0195 (3)0.0230 (3)0.0216 (3)−0.0007 (2)0.0089 (2)−0.0034 (2)
C40.0220 (3)0.0192 (3)0.0237 (3)0.0025 (2)0.0091 (3)0.0025 (2)
C50.0207 (3)0.0143 (2)0.0211 (3)0.0000 (2)0.0095 (2)0.00184 (19)
C60.0186 (3)0.0133 (2)0.0172 (2)−0.00044 (19)0.0088 (2)−0.00029 (17)
C70.0210 (3)0.0134 (2)0.0179 (2)0.0007 (2)0.0072 (2)−0.00046 (18)
C80.0195 (3)0.0127 (2)0.0166 (2)0.0000 (2)0.0083 (2)−0.00152 (17)
C90.0220 (3)0.0149 (2)0.0178 (2)−0.0033 (2)0.0097 (2)−0.00218 (19)
C100.0195 (3)0.0387 (4)0.0328 (4)0.0012 (3)0.0091 (3)−0.0044 (3)
Geometric parameters (Å, º) top
O1—N21.3647 (8)C3—C41.3983 (11)
O1—C71.4197 (8)C3—C101.5046 (12)
O2—C71.2089 (9)C4—C51.3893 (11)
O3—C91.2220 (9)C4—H4A0.9300
N1—N21.2971 (8)C5—C61.3870 (9)
N1—C81.3615 (8)C5—H5A0.9300
N1—C61.4428 (9)C7—C81.4225 (10)
C1—C61.3878 (9)C8—C91.4448 (9)
C1—C21.3924 (11)C9—H9A0.9300
C1—H1A0.9300C10—H10D0.9600
C2—C31.3971 (11)C10—H10A0.9600
C2—H2A0.9300C10—H10B0.9600
N2—O1—C7110.58 (5)C4—C5—H5A121.0
N2—N1—C8114.64 (6)C5—C6—C1122.72 (7)
N2—N1—C6117.76 (5)C5—C6—N1118.03 (6)
C8—N1—C6127.60 (6)C1—C6—N1119.25 (6)
N1—N2—O1105.66 (5)O2—C7—O1120.29 (7)
C6—C1—C2118.02 (7)O2—C7—C8136.05 (6)
C6—C1—H1A121.0O1—C7—C8103.66 (5)
C2—C1—H1A121.0N1—C8—C7105.44 (6)
C1—C2—C3121.19 (7)N1—C8—C9124.90 (6)
C1—C2—H2A119.4C7—C8—C9129.64 (6)
C3—C2—H2A119.4O3—C9—C8122.82 (7)
C2—C3—C4118.71 (7)O3—C9—H9A118.6
C2—C3—C10120.83 (7)C8—C9—H9A118.6
C4—C3—C10120.45 (7)C3—C10—H10D109.5
C5—C4—C3121.34 (7)C3—C10—H10A109.5
C5—C4—H4A119.3H10D—C10—H10A109.5
C3—C4—H4A119.3C3—C10—H10B109.5
C6—C5—C4118.01 (6)H10D—C10—H10B109.5
C6—C5—H5A121.0H10A—C10—H10B109.5
C8—N1—N2—O1−1.23 (7)N2—N1—C6—C1120.44 (7)
C6—N1—N2—O1178.51 (5)C8—N1—C6—C1−59.85 (9)
C7—O1—N2—N11.09 (7)N2—O1—C7—O2179.97 (6)
C6—C1—C2—C3−0.31 (11)N2—O1—C7—C8−0.58 (7)
C1—C2—C3—C41.07 (12)N2—N1—C8—C70.88 (7)
C1—C2—C3—C10−178.99 (8)C6—N1—C8—C7−178.84 (6)
C2—C3—C4—C5−0.81 (11)N2—N1—C8—C9−178.07 (6)
C10—C3—C4—C5179.25 (7)C6—N1—C8—C92.22 (10)
C3—C4—C5—C6−0.19 (11)O2—C7—C8—N1179.18 (8)
C4—C5—C6—C11.01 (11)O1—C7—C8—N1−0.13 (7)
C4—C5—C6—N1−178.80 (6)O2—C7—C8—C9−1.94 (13)
C2—C1—C6—C5−0.76 (11)O1—C7—C8—C9178.74 (6)
C2—C1—C6—N1179.05 (6)N1—C8—C9—O3166.06 (6)
N2—N1—C6—C5−59.74 (8)C7—C8—C9—O3−12.62 (11)
C8—N1—C6—C5119.96 (7)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1A···O2i0.932.413.2847 (9)156
C5—H5A···O3ii0.932.603.3489 (11)138
Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) −x+1, y−1/2, −z+5/2.

Experimental details

Crystal data
Chemical formulaC10H8N2O3
Mr204.18
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)10.5663 (4), 10.4088 (3), 8.9630 (3)
β (°) 108.222 (1)
V (Å3)936.34 (5)
Z4
Radiation typeMo Kα
µ (mm−1)0.11
Crystal size (mm)0.71 × 0.30 × 0.19
Data collection
DiffractometerBruker APEXII DUO CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.926, 0.980
No. of measured, independent and
observed [I > 2σ(I)] reflections		14437, 4906, 4091
Rint0.022
(sin θ/λ)max (Å−1)0.857
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.132, 1.07
No. of reflections4906
No. of parameters137
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.65, −0.31

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1A···O2i0.93002.41003.2847 (9)156.00
C5—H5A···O3ii0.93002.60003.3489 (11)138.00
Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) −x+1, y−1/2, −z+5/2.
 

Footnotes

‡Thomson Reuters ResearcherID: C-7576-2009.

§Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

The authors thank Universiti Sains Malaysia (USM) for the Research University Golden Goose grant (No. 1001/PFIZIK/811012). JHG also thanks USM for the award of a USM fellowship.

References

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ISSN: 2056-9890
Volume 66| Part 6| June 2010| Page o1303
https://doi.org/10.1107/S1600536810016417
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