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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 68| Part 4| April 2012| Page o941
doi:10.1107/S1600536812008677

5-(Phenyl­diazen­yl)tropolone

Tania N. Hill,a* Moeketsi S. Mangwaelaa and Gideon Steyla

aDepartment of Chemistry, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa
*Correspondence e-mail: tania.hill@gmail.com

(Received 13 February 2012; accepted 27 February 2012; online 3 March 2012)

The title compound [systematic name: (E)-2-hy­droxy-5-(phenyl­diazen­yl)cyclo­hepta-2,4,6-trien-1-one], C13H10N2O2, is essentially planar with an r.m.s. deviation of 0.036 (2) Å and a dihedral angle of 1.57 (8)° between the phenyl and tropolone rings. In the crystal, mol­ecules are linked by pairs of O—H⋯O hydrogen bonds into inversion dimers. The dimers are further connected by C—H⋯O hydrogen bonds and π–π stacking inter­actions, with centroid–centroid distances of 3.6934 (9) and 3.6282 (9) Å.

Related literature

For synthetic background, see: Gao & Zheng (2001[Gao, W. T. & Zheng, Z. (2001). Chin. Chem. Lett. 12, 103-106.]). For applications of azo-substituted tropolones, see: Mori et al. (2002[Mori, A., Uno, K. & Takeshita, H. (2002). Liq. Cryst. 29, 1539-1545.]). For related systems, see: Shimanouchi & Sasada (1973[Shimanouchi, H. & Sasada, Y. (1973). Acta Cryst. B29, 81-90.]); Steyl & Roodt (2006[Steyl, G. & Roodt, A. (2006). S. Afr. J. Chem. 59, 21-27.]). For a description of the Cambridge Structural Database, see: Allen (2002[Allen, F. H. (2002). Acta Cryst. B58, 380-388.]).

[Scheme 1]

Experimental

Crystal data

  • C13H10N2O2

  • Mr = 226.23

  • Monoclinic, P 21 /c

  • a = 6.2838 (2) Å

  • b = 24.8474 (13) Å

  • c = 8.0478 (3) Å

  • β = 122.255 (2)°

  • V = 1062.64 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 100 K

  • 0.35 × 0.32 × 0.05 mm
Data collection

  • Bruker X8 APEXII 4K KappaCCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2004[Bruker (2004). SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin. USA.]) Tmin = 0.967, Tmax = 0.995

  • 10621 measured reflections

  • 2669 independent reflections

  • 1925 reflections with I > 2σ(I)

  • Rint = 0.050
Refinement

  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.128

  • S = 1.05

  • 2669 reflections

  • 155 parameters

  • H-atom parameters constrained

  • Δρmax = 0.38 e Å−3

  • Δρmin = −0.24 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1—H1⋯O2 0.84 2.08 2.5754 (15) 117
C5—H5⋯O1i 0.95 2.40 3.1866 (19) 140
O1—H1⋯O2ii 0.84 1.96 2.6686 (15) 141
Symmetry codes: (i) x-1, y, z-1; (ii) -x+1, -y, -z+3.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 2004[Bruker (2004). SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin. USA.]); data reduction: SAINT-Plus; 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: DIAMOND (Brandenburg & Putz, 2005[Brandenburg, K. & Putz, H. (2005). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812008677/is5073sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812008677/is5073Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812008677/is5073Isup3.cml

checkCIF report


Comment top

Due to the special nature of the tropolone ring it demonstrates similar aromaticity as the benzene ring, undergoing electrophilic substitution reactions with electrophilic reagents. As part of our study on the functionlization of the tropolone moeity we report the structure of the title compound, (I) (Fig. 1), with the aim of contributing to a deeper understanding of troponoids and its functionlization. The original tropolone crystal structure was done by Shimanouchi & Sasada (1973). A search of the Cambridge structural database (CSD) (Allen, 2002) yielded thirteen troponoid compounds with a mono-substituted 5-position, of these only seven were with the tropolone backbone, none of which had an azo linking group.

In I the dihedral angle between the least-squares planes A (O1/O2/C1–C7/N1) and B (N2/C11–C16) was found to be 1.41 (6)°, resulting in an almost planar molecule with an r.m.s. deviation of 0.036 (2) Å. The largest variance from the molecular plane was found to be the O1 atom with a value of 0.058 (1) Å. The well known O—H···H interactions found for tropolone are present and lead to the formation of centrosymmetric dimers (Fig. 2). These interactions along with the last interaction found in Fig. 2, that of tropolone (C5) with an adjacent tropolone (O2) results in the formation of a planar sheet packing configuration (Fig 3). π–π Interactions were observed between the phenyl ring and the tropolone ring with a distance of 3.6934 (9) Å and two tropolone rings with a distance of 3.6282 (9) Å (Fig. 4).

Related literature top

For synthetic background, see: Gao & Zheng (2001). For applications of azo-substituted tropolones, see: Mori et al. (2002). For related systems, see: Shimanouchi & Sasada (1973); Steyl & Roodt (2006). For a description of the Cambridge Structural Database, see: Allen (2002).

Experimental top

Sodium nitrite (1.4 mmol) dissolved in water (1 ml) was added dropwise to a solution containing aniline (1.6 mmol), hydrochloric acid (2 ml, conc) and water (7 ml). Upon cooling the resultant mixture to ca. 4 °C it was slowly added to a solution of sodium hydroxide (1.8 mmol), tropolone (1.6 mmol) in water (4 ml) keeping the temperature < 5 °C. The resulting solution was stirred for 30 minutes, filtered and air-dried. Crystals suitable for X-ray diffraction were obtained by recrystalization with CHCl3.

Refinement top

All H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms.

Structure description top

Due to the special nature of the tropolone ring it demonstrates similar aromaticity as the benzene ring, undergoing electrophilic substitution reactions with electrophilic reagents. As part of our study on the functionlization of the tropolone moeity we report the structure of the title compound, (I) (Fig. 1), with the aim of contributing to a deeper understanding of troponoids and its functionlization. The original tropolone crystal structure was done by Shimanouchi & Sasada (1973). A search of the Cambridge structural database (CSD) (Allen, 2002) yielded thirteen troponoid compounds with a mono-substituted 5-position, of these only seven were with the tropolone backbone, none of which had an azo linking group.

In I the dihedral angle between the least-squares planes A (O1/O2/C1–C7/N1) and B (N2/C11–C16) was found to be 1.41 (6)°, resulting in an almost planar molecule with an r.m.s. deviation of 0.036 (2) Å. The largest variance from the molecular plane was found to be the O1 atom with a value of 0.058 (1) Å. The well known O—H···H interactions found for tropolone are present and lead to the formation of centrosymmetric dimers (Fig. 2). These interactions along with the last interaction found in Fig. 2, that of tropolone (C5) with an adjacent tropolone (O2) results in the formation of a planar sheet packing configuration (Fig 3). π–π Interactions were observed between the phenyl ring and the tropolone ring with a distance of 3.6934 (9) Å and two tropolone rings with a distance of 3.6282 (9) Å (Fig. 4).

For synthetic background, see: Gao & Zheng (2001). For applications of azo-substituted tropolones, see: Mori et al. (2002). For related systems, see: Shimanouchi & Sasada (1973); Steyl & Roodt (2006). For a description of the Cambridge Structural Database, see: Allen (2002).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound (50% probability displacement ellipsoids).
[Figure 2] Fig. 2. Intermolecular hydrogen bond interactions (dashed bonds) of the title compound. Symmetry codes: (i) x - 1, y, z - 1 (ii) 1 - x, -y, 3 - z. Non-relevant hydrogen atoms have been omitted for clarity.
[Figure 3] Fig. 3. A packing diagram of the title compound, illustrating the parallel sheet configuration as viewed along the a axis.
[Figure 4] Fig. 4. Partially filled unit cell of the title compound, illustrating π–π stacking interactions. Hydrogen atoms have been omitted for clarity.
(E)-2-hydroxy-5-(phenyldiazenyl)cyclohepta-2,4,6-trien-1-one top
Crystal data top
C13H10N2O2F(000) = 472
Mr = 226.23Dx = 1.414 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1666 reflections
a = 6.2838 (2) Åθ = 3.3–24.9°
b = 24.8474 (13) ŵ = 0.10 mm−1
c = 8.0478 (3) ÅT = 100 K
β = 122.255 (2)°Plate, red
V = 1062.64 (8) Å30.35 × 0.32 × 0.05 mm
Z = 4
Data collection top
Bruker X8 APEXII 4K KappaCCD
diffractometer		2669 independent reflections
Radiation source: sealed tube1925 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.050
Detector resolution: 512 pixels mm-1θmax = 28.4°, θmin = 3.1°
φ and ω scansh = −8→8
Absorption correction: multi-scan
(SADABS; Bruker, 2004)		k = −31→32
Tmin = 0.967, Tmax = 0.995l = −10→10
10621 measured reflections
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.048 w = 1/[σ2(Fo2) + (0.0566P)2 + 0.2818P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.128(Δ/σ)max < 0.001
S = 1.05Δρmax = 0.38 e Å−3
2669 reflectionsΔρmin = −0.24 e Å−3
155 parameters
Crystal data top
C13H10N2O2V = 1062.64 (8) Å3
Mr = 226.23Z = 4
Monoclinic, P21/cMo Kα radiation
a = 6.2838 (2) ŵ = 0.10 mm−1
b = 24.8474 (13) ÅT = 100 K
c = 8.0478 (3) Å0.35 × 0.32 × 0.05 mm
β = 122.255 (2)°
Data collection top
Bruker X8 APEXII 4K KappaCCD
diffractometer		2669 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)		1925 reflections with I > 2σ(I)
Tmin = 0.967, Tmax = 0.995Rint = 0.050
10621 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0480 restraints
wR(F2) = 0.128H-atom parameters constrained
S = 1.05Δρmax = 0.38 e Å−3
2669 reflectionsΔρmin = −0.24 e Å−3
155 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.6923 (3)0.05118 (6)1.3134 (2)0.0163 (3)
C20.8463 (3)0.07450 (7)1.2597 (2)0.0179 (3)
H21.01850.0771.36220.022*
C30.7891 (3)0.09498 (7)1.0787 (2)0.0175 (3)
H30.92690.10951.07580.021*
C40.5591 (3)0.09684 (7)0.9038 (2)0.0172 (3)
C50.3285 (3)0.07598 (7)0.8670 (2)0.0177 (3)
H50.19110.080.73520.021*
C60.2696 (3)0.05111 (7)0.9882 (2)0.0181 (4)
H60.0990.040.92620.022*
C70.4217 (3)0.03894 (6)1.1931 (2)0.0163 (3)
C110.6741 (3)0.16352 (6)0.5654 (2)0.0178 (3)
C120.4382 (3)0.16419 (7)0.3910 (2)0.0209 (4)
H120.29690.14890.38680.025*
C130.4112 (3)0.18728 (7)0.2241 (2)0.0247 (4)
H130.2510.18780.1050.03*
C140.6179 (3)0.20974 (7)0.2304 (2)0.0258 (4)
H140.59890.22550.11580.031*
C150.8514 (3)0.20909 (7)0.4036 (3)0.0252 (4)
H150.99220.22460.40760.03*
C160.8811 (3)0.18585 (7)0.5718 (2)0.0213 (4)
H161.04180.18520.69040.026*
N10.5284 (2)0.11965 (6)0.72852 (19)0.0194 (3)
N20.7201 (3)0.14104 (6)0.74631 (18)0.0196 (3)
O10.8030 (2)0.03666 (5)1.50085 (15)0.0204 (3)
H10.69560.02311.52020.031*
O20.3290 (2)0.01652 (5)1.27961 (15)0.0219 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0157 (8)0.0170 (8)0.0138 (7)0.0017 (6)0.0064 (6)−0.0002 (6)
C20.0134 (8)0.0216 (9)0.0144 (7)−0.0009 (6)0.0046 (6)−0.0004 (6)
C30.0162 (8)0.0195 (9)0.0185 (8)−0.0022 (6)0.0103 (7)−0.0004 (6)
C40.0185 (8)0.0174 (9)0.0151 (7)−0.0002 (6)0.0087 (6)−0.0003 (6)
C50.0154 (8)0.0204 (9)0.0142 (7)0.0007 (6)0.0058 (6)−0.0006 (6)
C60.0139 (7)0.0218 (9)0.0162 (7)−0.0007 (6)0.0065 (6)−0.0013 (6)
C70.0160 (8)0.0170 (9)0.0176 (7)0.0008 (6)0.0101 (6)−0.0010 (6)
C110.0223 (8)0.0149 (8)0.0186 (8)0.0008 (6)0.0125 (7)0.0004 (6)
C120.0217 (8)0.0198 (9)0.0214 (8)−0.0015 (7)0.0115 (7)0.0003 (6)
C130.0296 (9)0.0216 (10)0.0192 (8)0.0011 (7)0.0105 (7)0.0037 (7)
C140.0387 (10)0.0183 (9)0.0244 (9)−0.0006 (8)0.0195 (8)0.0037 (7)
C150.0315 (10)0.0197 (9)0.0324 (9)−0.0029 (7)0.0225 (8)0.0001 (7)
C160.0223 (8)0.0209 (9)0.0218 (8)−0.0001 (7)0.0125 (7)−0.0009 (7)
N10.0182 (7)0.0218 (8)0.0182 (7)−0.0015 (6)0.0097 (6)0.0009 (5)
N20.0204 (7)0.0213 (8)0.0188 (7)−0.0005 (6)0.0116 (6)0.0004 (6)
O10.0152 (6)0.0285 (7)0.0151 (5)−0.0033 (5)0.0065 (5)0.0033 (5)
O20.0162 (6)0.0306 (7)0.0185 (6)−0.0019 (5)0.0089 (5)0.0036 (5)
Geometric parameters (Å, º) top
C1—O11.3301 (18)C11—C161.389 (2)
C1—C21.380 (2)C11—C121.395 (2)
C1—C71.471 (2)C11—N21.4378 (19)
C2—C31.397 (2)C12—C131.385 (2)
C2—H20.95C12—H120.95
C3—C41.379 (2)C13—C141.389 (2)
C3—H30.95C13—H130.95
C4—C51.414 (2)C14—C151.383 (2)
C4—N11.4342 (19)C14—H140.95
C5—C61.362 (2)C15—C161.390 (2)
C5—H50.95C15—H150.95
C6—C71.429 (2)C16—H160.95
C6—H60.95N1—N21.2530 (19)
C7—O21.2521 (18)O1—H10.84
O1—C1—C2116.06 (13)C16—C11—C12120.25 (14)
O1—C1—C7114.31 (13)C16—C11—N2116.06 (14)
C2—C1—C7129.62 (14)C12—C11—N2123.69 (14)
C1—C2—C3130.28 (14)C13—C12—C11119.66 (15)
C1—C2—H2114.9C13—C12—H12120.2
C3—C2—H2114.9C11—C12—H12120.2
C4—C3—C2128.53 (15)C12—C13—C14120.16 (16)
C4—C3—H3115.7C12—C13—H13119.9
C2—C3—H3115.7C14—C13—H13119.9
C3—C4—C5126.89 (14)C15—C14—C13120.03 (15)
C3—C4—N1122.36 (14)C15—C14—H14120
C5—C4—N1110.72 (13)C13—C14—H14120
C6—C5—C4131.02 (15)C14—C15—C16120.34 (16)
C6—C5—H5114.5C14—C15—H15119.8
C4—C5—H5114.5C16—C15—H15119.8
C5—C6—C7130.70 (15)C11—C16—C15119.55 (15)
C5—C6—H6114.7C11—C16—H16120.2
C7—C6—H6114.7C15—C16—H16120.2
O2—C7—C6120.84 (14)N2—N1—C4116.00 (13)
O2—C7—C1116.31 (14)N1—N2—C11112.83 (13)
C6—C7—C1122.85 (14)C1—O1—H1109.5
O1—C1—C2—C3−178.41 (16)C16—C11—C12—C130.0 (2)
C7—C1—C2—C32.7 (3)N2—C11—C12—C13179.29 (15)
C1—C2—C3—C4−0.4 (3)C11—C12—C13—C14−0.1 (3)
C2—C3—C4—C5−2.9 (3)C12—C13—C14—C150.0 (3)
C2—C3—C4—N1179.51 (16)C13—C14—C15—C160.3 (3)
C3—C4—C5—C62.2 (3)C12—C11—C16—C150.3 (2)
N1—C4—C5—C6−179.90 (17)N2—C11—C16—C15−179.08 (15)
C4—C5—C6—C71.3 (3)C14—C15—C16—C11−0.4 (3)
C5—C6—C7—O2178.42 (17)C3—C4—N1—N2−4.4 (2)
C5—C6—C7—C1−2.1 (3)C5—C4—N1—N2177.61 (14)
O1—C1—C7—O2−0.2 (2)C4—N1—N2—C11−179.34 (13)
C2—C1—C7—O2178.73 (16)C16—C11—N2—N1−177.26 (14)
O1—C1—C7—C6−179.64 (14)C12—C11—N2—N13.4 (2)
C2—C1—C7—C6−0.7 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O20.842.082.5754 (15)117
C5—H5···O1i0.952.403.1866 (19)140
O1—H1···O2ii0.841.962.6686 (15)141
Symmetry codes: (i) x−1, y, z−1; (ii) −x+1, −y, −z+3.

Experimental details

Crystal data
Chemical formulaC13H10N2O2
Mr226.23
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)6.2838 (2), 24.8474 (13), 8.0478 (3)
β (°) 122.255 (2)
V (Å3)1062.64 (8)
Z4
Radiation typeMo Kα
µ (mm−1)0.10
Crystal size (mm)0.35 × 0.32 × 0.05
Data collection
DiffractometerBruker X8 APEXII 4K KappaCCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2004)
Tmin, Tmax0.967, 0.995
No. of measured, independent and
observed [I > 2σ(I)] reflections		10621, 2669, 1925
Rint0.050
(sin θ/λ)max (Å−1)0.669
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.128, 1.05
No. of reflections2669
No. of parameters155
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.38, −0.24

Computer programs: APEX2 (Bruker, 2005), SAINT-Plus (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg & Putz, 2005), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O20.842.082.5754 (15)117
C5—H5···O1i0.952.403.1866 (19)140
O1—H1···O2ii0.841.962.6686 (15)141
Symmetry codes: (i) x−1, y, z−1; (ii) −x+1, −y, −z+3.
 

Acknowledgements

Financial assistance from the University of the Free State is gratefully acknowledged. We also express our gratitude towards SASOL and the South African National Research Foundation (SA-NRF/THRIP) for financial support of this project. Part of this material is based on work supported by the SA-NRF/THRIP under grant No. GUN 2068915. Opinions, findings, conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the SA-NRF.

References

First citationAllen, F. H. (2002). Acta Cryst. B58, 380–388.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
 First citationBrandenburg, K. & Putz, H. (2005). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
 First citationBruker (2004). SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin. USA.  Google Scholar
 First citationBruker (2005). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationFarrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.  CrossRef CAS IUCr Journals Google Scholar
 First citationGao, W. T. & Zheng, Z. (2001). Chin. Chem. Lett. 12, 103–106.  CAS Google Scholar
 First citationMori, A., Uno, K. & Takeshita, H. (2002). Liq. Cryst. 29, 1539–1545.  Web of Science CrossRef CAS Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
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ISSN: 2056-9890
Volume 68| Part 4| April 2012| Page o941
doi:10.1107/S1600536812008677
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