organic compounds
3-(2-Acetamidophenyl)sydnone
aDepartment of Chemistry, Wright State University, 3640 Colonel Glenn Hwy, Dayton, Ohio 45435, USA
*Correspondence e-mail: david.grossie@wright.edu
10H9N3O3, the aromatic substitutent is 2-acetamidophenyl. The two planar ring fragments are twisted relative to one another, with a interplanar angle of 63.13 (5)°. The molecules are packed into the via π–π interactions between the phenyl rings [interplanar separation = 3.4182 (4) Å] and between the sydnone rings [interplanar separation = 3.2095 (4) Å]. N—H⋯O and C—H⋯O hydrogen bonding is also found internally and externally to the molecule.
are unusual containing a five-membered heterocyclic ring. Generally for stability, substitution at the N-3 position by an aromatic fragment is necessary. In the title compound, CRelated literature
For more information on the sydnone family of compounds, see: Ohta & Kato (1969). For the synthesis and structural information, see: Grossie et al. (1992, 2001, 2007); Riddle et al. 2004a,b,c; Hope & Thiessen (1968); Hodson & Turnbull (1985); Baker & Ollis (1957). For a description of the Cambridge Structural Database, see: Allen (2002). For related literature, see: Kier & Roche (1966); Matsunaga (1957); Ollis & Ramsden (1976).
Experimental
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2003); cell SAINT-Plus (Bruker, 2003); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008) and OSCAIL X, (McArdle, 2008); software used to prepare material for publication: enCIFer (Allen et al., 2004), publCIF (Westrip, 2009) and PLATON (Spek, 2009).
Supporting information
10.1107/S1600536809005066/rk2130sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809005066/rk2130Isup2.hkl
3–(2–Aminophenyl)sydnone (0.5 g, 2.82 mmol) was dissolved in acetic anhydride (10 ml) and stirred for 20 h. Evaporation on standing overnight gave a light yellow oil which was crystallized from methylene chloride/petroleum ether to give 3–(2–acetamidophenyl)sydnone (0.42 g, 68%), mp 349–351 K; IR–spectra: 3310, 3290 (N—H str), 3130 (sydnone C—H str), 1740 (sydnone C═O str) cm-1. The 1H NMR (CDCl3): δ 2.0 (s, 3H), 6.83 (s, 1H), 7.65 (m, 4H), 9.65 (s, 1H). Anal. Calcd. for C10H9N3O3: C, 54.79; H, 4.11; N, 19.18. Found; C, 54.90; H, 4.17; N, 18.89.
The amide H atom was located in a different Fourier map and refined with an isotropic displacement parameter. The positional parameters were allow to refine freely. The methyl and benzene H atoms were included in geometrically calculated positions, with C—H distances of 0.98Å and 0.96Å, respectively, and Uiso(H) = 1.3Ueq(C).
Data collection: SMART (Bruker, 2003); cell
SAINT-Plus (Bruker, 2003); data reduction: SAINT-Plus (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008) and OSCAIL X, (McArdle, 2008); software used to prepare material for publication: enCIFer (Allen et al., 2004), publCIF (Westrip, 2009) and PLATON (Spek, 2009).Fig. 1. Molecular structure of title compound with the atom numbering scheme. The displacement ellipsoids are drawn at 50% probability level. The H atoms are presented as a small spheres of arbitrary radius. |
C10H9N3O3 | F(000) = 456 |
Mr = 219.20 | Dx = 1.477 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 4272 reflections |
a = 7.7348 (4) Å | θ = 2.7–31.7° |
b = 13.7212 (7) Å | µ = 0.11 mm−1 |
c = 9.6698 (5) Å | T = 173 K |
β = 106.083 (1)° | Block, white |
V = 986.10 (9) Å3 | 0.45 × 0.40 × 0.26 mm |
Z = 4 |
Bruker SMART APEXII diffractometer | 3053 independent reflections |
Radiation source: Fine–focus sealed tube | 2711 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.017 |
ω scans | θmax = 32.0°, θmin = 2.7° |
Absorption correction: multi-scan (SADABS; Bruker, 2003) | h = −11→11 |
Tmin = 0.895, Tmax = 0.970 | k = −19→14 |
8741 measured reflections | l = −14→14 |
Refinement on F2 | Primary atom site location: Direct |
Least-squares matrix: Full | Secondary atom site location: Difmap |
R[F2 > 2σ(F2)] = 0.038 | Hydrogen site location: Geom |
wR(F2) = 0.108 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | w = 1/[σ2(Fo2) + (0.058P)2 + 0.315P] where P = (Fo2 + 2Fc2)/3 |
3053 reflections | (Δ/σ)max < 0.001 |
150 parameters | Δρmax = 0.44 e Å−3 |
0 restraints | Δρmin = −0.24 e Å−3 |
C10H9N3O3 | V = 986.10 (9) Å3 |
Mr = 219.20 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.7348 (4) Å | µ = 0.11 mm−1 |
b = 13.7212 (7) Å | T = 173 K |
c = 9.6698 (5) Å | 0.45 × 0.40 × 0.26 mm |
β = 106.083 (1)° |
Bruker SMART APEXII diffractometer | 3053 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2003) | 2711 reflections with I > 2σ(I) |
Tmin = 0.895, Tmax = 0.970 | Rint = 0.017 |
8741 measured reflections |
R[F2 > 2σ(F2)] = 0.038 | 0 restraints |
wR(F2) = 0.108 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | Δρmax = 0.44 e Å−3 |
3053 reflections | Δρmin = −0.24 e Å−3 |
150 parameters |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. Least–Squares Planes. Sydnone Ring. Defining atoms: O1 0.004 (1)Å, N2 -0.003 (1)Å, N3 0.000 (1)Å, C4 0.003 (1)Å, C5 -0.004 (1)Å; other atoms: O5 0.002 (1)Å, C11 0.081 (1)Å. Phenyl Ring. Defining atoms: C11 0.009 (1)Å, C12 -0.004 (1)Å, C13 -0.003 (1)Å, C14 0.006 (1)Å, C15 -0.002 (1)Å, C16 -0.006 (1)Å; other atoms: O17A 0.710 (1)Å, N12 -0.120 (1)Å, C17 0.159 (1)Å, C18 -0.233 (1)Å. |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.84105 (9) | 0.07745 (5) | 0.51445 (7) | 0.01803 (16) | |
N3 | 0.82573 (10) | 0.08267 (6) | 0.29241 (8) | 0.01461 (16) | |
N2 | 0.76980 (11) | 0.03010 (6) | 0.38528 (9) | 0.01838 (18) | |
C4 | 0.92672 (12) | 0.16064 (7) | 0.34726 (10) | 0.01603 (18) | |
H4 | 0.9791 | 0.2067 | 0.2959 | 0.021* | |
C5 | 0.94005 (12) | 0.16089 (7) | 0.49604 (10) | 0.01573 (18) | |
O5 | 1.01261 (10) | 0.21147 (6) | 0.59934 (8) | 0.01993 (16) | |
C11 | 0.78190 (12) | 0.04762 (7) | 0.14601 (9) | 0.01569 (18) | |
C12 | 0.67371 (12) | 0.10348 (7) | 0.03402 (10) | 0.01569 (18) | |
N12 | 0.59485 (11) | 0.19068 (6) | 0.06408 (8) | 0.01579 (16) | |
H12 | 0.579 (2) | 0.1987 (11) | 0.1492 (16) | 0.024 (3)* | |
C13 | 0.63770 (14) | 0.06464 (8) | −0.10516 (10) | 0.0210 (2) | |
H13 | 0.5644 | 0.1005 | −0.1853 | 0.027* | |
C14 | 0.70713 (15) | −0.02531 (8) | −0.12794 (11) | 0.0231 (2) | |
H14 | 0.6820 | −0.0503 | −0.2242 | 0.030* | |
C15 | 0.81211 (14) | −0.08014 (8) | −0.01474 (11) | 0.0219 (2) | |
H15 | 0.8582 | −0.1425 | −0.0322 | 0.028* | |
C16 | 0.84924 (13) | −0.04322 (7) | 0.12408 (11) | 0.01917 (19) | |
H16 | 0.9207 | −0.0800 | 0.2040 | 0.025* | |
C17 | 0.52287 (12) | 0.26254 (7) | −0.03227 (10) | 0.01474 (17) | |
O17A | 0.53832 (10) | 0.26491 (6) | −0.15559 (7) | 0.02026 (16) | |
C18 | 0.42424 (13) | 0.34120 (8) | 0.02328 (10) | 0.01933 (19) | |
H18A | 0.5042 | 0.3972 | 0.0544 | 0.025* | |
H18B | 0.3858 | 0.3162 | 0.1050 | 0.025* | |
H18C | 0.3184 | 0.3615 | −0.0534 | 0.025* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0216 (3) | 0.0193 (4) | 0.0135 (3) | −0.0025 (3) | 0.0055 (2) | 0.0016 (2) |
N3 | 0.0158 (3) | 0.0144 (4) | 0.0133 (3) | 0.0005 (3) | 0.0036 (3) | 0.0016 (3) |
N2 | 0.0218 (4) | 0.0187 (4) | 0.0148 (3) | −0.0033 (3) | 0.0053 (3) | 0.0015 (3) |
C4 | 0.0183 (4) | 0.0157 (4) | 0.0143 (4) | −0.0019 (3) | 0.0049 (3) | 0.0007 (3) |
C5 | 0.0166 (4) | 0.0155 (4) | 0.0155 (4) | 0.0016 (3) | 0.0051 (3) | 0.0020 (3) |
O5 | 0.0242 (3) | 0.0201 (4) | 0.0155 (3) | −0.0006 (3) | 0.0055 (3) | −0.0021 (3) |
C11 | 0.0169 (4) | 0.0170 (4) | 0.0130 (4) | −0.0004 (3) | 0.0038 (3) | −0.0013 (3) |
C12 | 0.0174 (4) | 0.0159 (4) | 0.0137 (4) | 0.0007 (3) | 0.0043 (3) | −0.0008 (3) |
N12 | 0.0201 (4) | 0.0167 (4) | 0.0108 (3) | 0.0029 (3) | 0.0047 (3) | 0.0003 (3) |
C13 | 0.0250 (5) | 0.0219 (5) | 0.0144 (4) | 0.0030 (4) | 0.0027 (3) | −0.0028 (3) |
C14 | 0.0282 (5) | 0.0223 (5) | 0.0186 (4) | 0.0013 (4) | 0.0060 (4) | −0.0062 (4) |
C15 | 0.0243 (5) | 0.0175 (5) | 0.0244 (5) | 0.0015 (3) | 0.0074 (4) | −0.0042 (4) |
C16 | 0.0201 (4) | 0.0160 (5) | 0.0208 (4) | 0.0016 (3) | 0.0047 (3) | 0.0004 (3) |
C17 | 0.0148 (4) | 0.0163 (4) | 0.0130 (4) | −0.0016 (3) | 0.0037 (3) | 0.0000 (3) |
O17A | 0.0294 (4) | 0.0199 (4) | 0.0130 (3) | −0.0011 (3) | 0.0084 (3) | 0.0009 (3) |
C18 | 0.0219 (4) | 0.0201 (5) | 0.0174 (4) | 0.0059 (3) | 0.0078 (3) | 0.0027 (3) |
O1—N2 | 1.3801 (10) | N12—H12 | 0.871 (15) |
O1—C5 | 1.4158 (12) | C13—C14 | 1.3878 (15) |
N3—N2 | 1.3150 (11) | C13—H13 | 0.9600 |
N3—C4 | 1.3440 (12) | C14—C15 | 1.3897 (15) |
N3—C11 | 1.4437 (12) | C14—H14 | 0.9600 |
C4—C5 | 1.4136 (12) | C15—C16 | 1.3883 (14) |
C4—H4 | 0.9600 | C15—H15 | 0.9600 |
C5—O5 | 1.2181 (12) | C16—H16 | 0.9600 |
C11—C16 | 1.3897 (14) | C17—O17A | 1.2314 (11) |
C11—C12 | 1.3994 (13) | C17—C18 | 1.5041 (14) |
C12—C13 | 1.4018 (13) | C18—H18A | 0.9800 |
C12—N12 | 1.4093 (12) | C18—H18B | 0.9800 |
N12—C17 | 1.3649 (12) | C18—H18C | 0.9800 |
N2—O1—C5 | 111.17 (7) | C14—C13—H13 | 119.7 |
N2—N3—C4 | 115.61 (8) | C12—C13—H13 | 119.7 |
N2—N3—C11 | 117.04 (8) | C13—C14—C15 | 121.59 (9) |
C4—N3—C11 | 127.23 (8) | C13—C14—H14 | 119.2 |
N3—N2—O1 | 103.62 (7) | C15—C14—H14 | 119.2 |
N3—C4—C5 | 105.91 (8) | C16—C15—C14 | 118.90 (9) |
N3—C4—H4 | 127.0 | C16—C15—H15 | 120.6 |
C5—C4—H4 | 127.0 | C14—C15—H15 | 120.6 |
O5—C5—C4 | 136.32 (9) | C15—C16—C11 | 119.27 (9) |
O5—C5—O1 | 120.00 (8) | C15—C16—H16 | 120.4 |
C4—C5—O1 | 103.68 (8) | C11—C16—H16 | 120.4 |
C16—C11—C12 | 122.84 (9) | O17A—C17—N12 | 123.33 (9) |
C16—C11—N3 | 116.89 (8) | O17A—C17—C18 | 121.46 (9) |
C12—C11—N3 | 120.26 (8) | N12—C17—C18 | 115.21 (8) |
C11—C12—C13 | 116.86 (9) | C17—C18—H18A | 109.5 |
C11—C12—N12 | 120.37 (8) | C17—C18—H18B | 109.5 |
C13—C12—N12 | 122.58 (8) | H18A—C18—H18B | 109.5 |
C17—N12—C12 | 126.20 (8) | C17—C18—H18C | 109.5 |
C17—N12—H12 | 114.7 (10) | H18A—C18—H18C | 109.5 |
C12—N12—H12 | 118.8 (10) | H18B—C18—H18C | 109.5 |
C14—C13—C12 | 120.52 (9) | ||
C4—N3—N2—O1 | −0.25 (11) | N3—C11—C12—C13 | 179.79 (9) |
C11—N3—N2—O1 | 176.13 (7) | C16—C11—C12—N12 | 173.82 (9) |
C5—O1—N2—N3 | 0.65 (10) | N3—C11—C12—N12 | −5.04 (14) |
N2—N3—C4—C5 | −0.24 (11) | C11—C12—N12—C17 | 163.84 (9) |
C11—N3—C4—C5 | −176.19 (8) | C13—C12—N12—C17 | −21.28 (15) |
N3—C4—C5—O5 | 179.52 (11) | C11—C12—C13—C14 | 0.22 (15) |
N3—C4—C5—O1 | 0.61 (10) | N12—C12—C13—C14 | −174.83 (10) |
N2—O1—C5—O5 | −179.93 (8) | C12—C13—C14—C15 | 0.73 (17) |
N2—O1—C5—C4 | −0.80 (10) | C13—C14—C15—C16 | −0.59 (17) |
N2—N3—C11—C16 | −60.99 (12) | C14—C15—C16—C11 | −0.50 (16) |
C4—N3—C11—C16 | 114.91 (11) | C12—C11—C16—C15 | 1.51 (15) |
N2—N3—C11—C12 | 117.94 (10) | N3—C11—C16—C15 | −179.60 (9) |
C4—N3—C11—C12 | −66.16 (13) | C12—N12—C17—O17A | −9.29 (15) |
C16—C11—C12—C13 | −1.34 (15) | C12—N12—C17—C18 | 171.74 (9) |
D—H···A | D—H | H···A | D···A | D—H···A |
N12—H12···O17Ai | 0.876 (15) | 2.056 (15) | 2.9272 (10) | 173.2 (14) |
C4—H4···O5ii | 0.96 | 2.28 | 3.1860 (12) | 156 |
C13—H13···O17A | 0.96 | 2.29 | 2.8587 (14) | 117 |
C15—H15···O5iii | 0.96 | 2.41 | 3.3612 (14) | 173 |
C16—H16···O5iv | 0.96 | 2.57 | 3.4700 (13) | 157 |
C18—H18B···O17Ai | 0.98 | 2.54 | 3.3201 (12) | 136 |
Symmetry codes: (i) x, −y+1/2, z+1/2; (ii) x, −y+1/2, z−1/2; (iii) −x+2, y−1/2, −z+1/2; (iv) −x+2, −y, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C10H9N3O3 |
Mr | 219.20 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 173 |
a, b, c (Å) | 7.7348 (4), 13.7212 (7), 9.6698 (5) |
β (°) | 106.083 (1) |
V (Å3) | 986.10 (9) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.11 |
Crystal size (mm) | 0.45 × 0.40 × 0.26 |
Data collection | |
Diffractometer | Bruker SMART APEXII diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2003) |
Tmin, Tmax | 0.895, 0.970 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8741, 3053, 2711 |
Rint | 0.017 |
(sin θ/λ)max (Å−1) | 0.745 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.038, 0.108, 1.05 |
No. of reflections | 3053 |
No. of parameters | 150 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.44, −0.24 |
Computer programs: SMART (Bruker, 2003), SAINT-Plus (Bruker, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Mercury (Macrae et al., 2008) and OSCAIL X, (McArdle, 2008), enCIFer (Allen et al., 2004), publCIF (Westrip, 2009) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
N12—H12···O17Ai | 0.876 (15) | 2.056 (15) | 2.9272 (10) | 173.2 (14) |
C4—H4···O5ii | 0.96 | 2.28 | 3.1860 (12) | 156 |
C13—H13···O17A | 0.96 | 2.29 | 2.8587 (14) | 117 |
C15—H15···O5iii | 0.96 | 2.41 | 3.3612 (14) | 173 |
C16—H16···O5iv | 0.96 | 2.57 | 3.4700 (13) | 157 |
C18—H18B···O17Ai | 0.98 | 2.54 | 3.3201 (12) | 136 |
Symmetry codes: (i) x, −y+1/2, z+1/2; (ii) x, −y+1/2, z−1/2; (iii) −x+2, y−1/2, −z+1/2; (iv) −x+2, −y, −z+1. |
Acknowledgements
The authors acknowledge the diffractometer time granted by A. Hunter, Youngstown State University.
References
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Sydnones are the most widely studied members of the general class of mesoionic compounds (Ohta & Kato, 1969). They are the products of dehydration of N–nitroso–α–aminoacids (Hope & Thiessen, 1968), and they undergo facile electrophilic aromatic subtitution on the sydnone ring. The selectivity on the sydnone ring (and not the aryl ring) can be attributed to the activated nature of the sydnone ring (Matsunaga, 1957) and its deactivating effect upon the attached aryl ring (the N3 position bears a considerable fractional positive charge (Kier & Roche, 1966)).
The 3–(2–acetamidophenyl)sydnone was synthesized to investigate its bromination and to probe the parameters controlling the site of electrophilic attack, both from mechanistic and synthetic standpoints. The sydnone ring is found to be planar. The ring bond distances O–N, N–N, N–C and C–C are similar to those of related compounds. However, the C—O bond distance of 1.4158 (12)Å, is longer than that of the C—O bond in a furane ring. As mentioned in previous paper (Hodson & Turnbull, 1985), the exocyclic C═O distance (1.2181 (12)Å) does not support the formulation of Baker & Ollis (1957), which involves the delocalization of a positive charge on the ring, and a negative charge on the exocyclic oxygen.
The molecules pack along the body diagonal within the unit cell, in symmetry related pairs with the phenyl rings lying parallel to each other, separated by a distance of 3.4182 (4)Å. The pairs of molecules are further paired through interaction of the sydnone rings in adjacent molecules, which are positioned parallel to each other at a distance of 3.2095 (4)Å. The molecules are connected laterally through hydrogen bonding between the sydnone and acetamide O atoms and phenyl, and amide H atoms. Hydrogen bond parameters are tabulated in Table 1.
As expected the sydnone ring was similar in metrical parameters to sydnone structures previously determined, in this laboratory (Grossie et al., 1992, 2001, 2007; Riddle et al. 2004a,b,c) and as found in the Cambridge Structural Database vers. 5.30 (Allen, 2002).