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Dibenzo[b,e]thiepin-11(6H)-one

aDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA, bDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India, cDepartment of Chemistry, Howard University, 525 College Street NW, Washington, DC 20059, USA, and dDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri 574 199, India
*Correspondence e-mail: jjasinski@keene.edu

(Received 6 December 2009; accepted 7 January 2010; online 13 January 2010)

In the title compound, C14H10OS, the seven-membered thiepin ring adopts a distorted boat conformation with the dihedral angle between the mean planes of the two fused benzene rings being 56.5 (1)°.

Related literature

For the biological and chiroptical properties of dibenzo[c,e]thiepine derivatives, see: Rajsner et al. (1969[Rajsner, M., Svatek, E., Seidlova, V., Adlerova, E. & Protiva, M. (1969). Collect. Czech. Chem. Commun. 34, 1278.], 1971[Rajsner, M., Protiva, M. & Metysova, J. (1971). Czech. Pat. Appl. CS 143737.]); Truce & Emrick (1956[Truce, W. E. & Emrick, D. D. (1956). J. Am. Chem. Soc. 78, 6130-6137.]); Tomascovic et al. (2000[Tomascovic, L. L., Arneri, R. S., Brundic, A. H., Nagl, A., Mintas, M. & Sandtrom, J. (2000). Helv. Chim. Acta, 83, 479-493.]). For spectral, structural and theoretical studies of eight related 6-aryl­idenedibenzo[b,e]thiepin-11-one-5,5-dioxides, see: Kolehmainen et al. (2007[Kolehmainen, E., Laihia, K., Valkonen, A., Sievänen, E., Nissinen, M., Rudorf, W.-D., Loos, D., Perjessy, A., Samalikova, M., Sustekova, Z., Florea, S. & Wybraziec, J. (2007). J. Mol. Struct. 839, 94-98.]). For DFT calculations and the GAUSSIAN03 program package, see: Schmidt & Polik (2007[Schmidt, J. R. & Polik, W. F. (2007). WebMO Pro. WebMO, LLC: Holland, MI, USA. Available from http://www.webmo.net.]); Frisch et al. (2004[Frisch, M. J., et al. (2004). GAUSSIAN03. Gaussian Inc., Wallingford, CT, USA.]). 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
  • C14H10OS

  • Mr = 226.28

  • Orthorhombic, P n a 21

  • a = 14.6208 (11) Å

  • b = 4.3503 (3) Å

  • c = 16.9023 (13) Å

  • V = 1075.07 (14) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.27 mm−1

  • T = 110 K

  • 0.47 × 0.42 × 0.12 mm

Data collection
  • Oxford Diffraction Gemini R CCD diffractometer

  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007[Oxford Diffraction (2007). CrysAlis PRO and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]) Tmin = 0.769, Tmax = 1.000

  • 2124 measured reflections

  • 1322 independent reflections

  • 1291 reflections with I > 2σ(I)

  • Rint = 0.022

Refinement
  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.104

  • S = 1.06

  • 1322 reflections

  • 145 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.42 e Å−3

  • Δρmin = −0.35 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 242 Friedel pairs

  • Flack parameter: −0.57 (13)

Data collection: CrysAlis PRO (Oxford Diffraction, 2007[Oxford Diffraction (2007). CrysAlis PRO and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL and WebMOPro (Schmidt & Polik, 2007[Schmidt, J. R. & Polik, W. F. (2007). WebMO Pro. WebMO, LLC: Holland, MI, USA. Available from http://www.webmo.net.]).

Supporting information


Comment top

The title compound is used as an intermediate for the synthesis of dosulepin, which is an antidepressant of the tricyclic family. Dosulepin works by preventing serotonin and noradrenaline from being reabsorbed in the brain. This helps prolong the mood lightening effect of any released noradrenaline and serotonin, thus relieving depression. The dibenzo[c,e]thiepine derivatives (Truce et al., 1956) exhibit remarkable chiroptical properties (Tomascovic et al., 2000). The dibenzo[b,e]thiepin-5,5-dioxide derivatives are known to possess antihistaminic and antiallergenic activities (Rajsner et al., 1971). In addition, by aminoalkylation of 6,11-dihydrodibenzo[b,e]thiepin-5,5-dioxide and the corresponding 11-ketone, compounds with neurotropic and psychotropic activities have been reported (Rajsner et al., 1969). In addition, the comparative NMR and IR spectral, X-ray structural and theoretical studies of eight 6-arylidenedibenzo[b,e]thiepin-11-one-5,5-dioxides have been reported (Kolehmainen et al., 2007). In view of the importance of thiepines, this paper reports the crystal structure of the title compound.

The seven-membered thiepin ring adopts a distorted boat conformation with the dihedral angle between the mean planes of the two fused benzene rings measuring 56.5 (1)° (Fig. 1). This conformation is assisted by sp3 hybridization of atom C8 within the ring. The ketone oxygen atom (O) lies in an equatorial position from the ring on opposite sides of the C8 and S atoms [C3—C2—C1—O = 31.1 (4)° and C13—C14—C1—O = -50.7 (4)°]. Bond lengths and bond angles are all within expected ranges (Allen, 2002).

Following a geometry optimization density functional theory calculation (Schmidt & Polik, 2007), in vacuo, at the B3LYP 6–31-G(d) level with the GAUSSIAN03 program package (Frisch et al., 2004) the angle between the mean planes of the two benzene rings becomes 46.2 (6)°, a decrease of 14.2 (5)°. The C3—C2—C1—O and C13—C14—C1—O torsion angles become 12.8 (2)°) and -36.9 (1)°, a decrease of 18.3 (2)° and 13.8 (3)°, respectively.

Related literature top

For the biological and chiroptical properties of dibenzo[c,e]thiepine derivatives, see: Rajsner et al. (1969, 1971); Truce et al. (1956); Tomascovic et al. (2000). For spectral, structural and theoretical studies of eight related 6-arylidenedibenzo[b,e]thiepin-11-one-5,5-dioxides, see: Kolehmainen et al. (2007). For DFT calculations and the GAUSSIAN03 program package, see: Schmidt & Polik (2007); Frisch et al. (2004). For a description of the Cambridge Structural Database, see: Allen (2002).

Experimental top

The title compound was obtained as a gift sample from R. L. Fine Chem, Bangalore, India. The compound was used without further purification. X-ray quality crystals (m.p. 347–349 K) were obtained by slow evaporation of a solution in methanol.

Refinement top

H atoms were placed in their calculated positions and then refined using the riding model with C–H = 0.95–0.99 Å, and with Uiso(H) = 1.18–1.21Ueq(C). The absolute structure could not be determined reliably due to the low Friedel pair coverage.

Structure description top

The title compound is used as an intermediate for the synthesis of dosulepin, which is an antidepressant of the tricyclic family. Dosulepin works by preventing serotonin and noradrenaline from being reabsorbed in the brain. This helps prolong the mood lightening effect of any released noradrenaline and serotonin, thus relieving depression. The dibenzo[c,e]thiepine derivatives (Truce et al., 1956) exhibit remarkable chiroptical properties (Tomascovic et al., 2000). The dibenzo[b,e]thiepin-5,5-dioxide derivatives are known to possess antihistaminic and antiallergenic activities (Rajsner et al., 1971). In addition, by aminoalkylation of 6,11-dihydrodibenzo[b,e]thiepin-5,5-dioxide and the corresponding 11-ketone, compounds with neurotropic and psychotropic activities have been reported (Rajsner et al., 1969). In addition, the comparative NMR and IR spectral, X-ray structural and theoretical studies of eight 6-arylidenedibenzo[b,e]thiepin-11-one-5,5-dioxides have been reported (Kolehmainen et al., 2007). In view of the importance of thiepines, this paper reports the crystal structure of the title compound.

The seven-membered thiepin ring adopts a distorted boat conformation with the dihedral angle between the mean planes of the two fused benzene rings measuring 56.5 (1)° (Fig. 1). This conformation is assisted by sp3 hybridization of atom C8 within the ring. The ketone oxygen atom (O) lies in an equatorial position from the ring on opposite sides of the C8 and S atoms [C3—C2—C1—O = 31.1 (4)° and C13—C14—C1—O = -50.7 (4)°]. Bond lengths and bond angles are all within expected ranges (Allen, 2002).

Following a geometry optimization density functional theory calculation (Schmidt & Polik, 2007), in vacuo, at the B3LYP 6–31-G(d) level with the GAUSSIAN03 program package (Frisch et al., 2004) the angle between the mean planes of the two benzene rings becomes 46.2 (6)°, a decrease of 14.2 (5)°. The C3—C2—C1—O and C13—C14—C1—O torsion angles become 12.8 (2)°) and -36.9 (1)°, a decrease of 18.3 (2)° and 13.8 (3)°, respectively.

For the biological and chiroptical properties of dibenzo[c,e]thiepine derivatives, see: Rajsner et al. (1969, 1971); Truce et al. (1956); Tomascovic et al. (2000). For spectral, structural and theoretical studies of eight related 6-arylidenedibenzo[b,e]thiepin-11-one-5,5-dioxides, see: Kolehmainen et al. (2007). For DFT calculations and the GAUSSIAN03 program package, see: Schmidt & Polik (2007); Frisch et al. (2004). For a description of the Cambridge Structural Database, see: Allen (2002).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2007); cell refinement: CrysAlis PRO (Oxford Diffraction, 2007); data reduction: CrysAlis PRO (Oxford Diffraction, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and WebMOPro (Schmidt & Polik, 2007).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound, showing atom-labeling scheme and 50% probability displacement ellipsoids.
Dibenzo[b,e]thiepin-11(6H)-one top
Crystal data top
C14H10OSF(000) = 472
Mr = 226.28Dx = 1.398 Mg m3
Orthorhombic, Pna21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2nCell parameters from 1716 reflections
a = 14.6208 (11) Åθ = 4.0–73.6°
b = 4.3503 (3) ŵ = 0.27 mm1
c = 16.9023 (13) ÅT = 110 K
V = 1075.07 (14) Å3Plate, colorless
Z = 40.47 × 0.42 × 0.12 mm
Data collection top
Oxford Diffraction Gemini R CCD
diffractometer
1322 independent reflections
Radiation source: fine-focus sealed tube1291 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.022
Detector resolution: 10.5081 pixels mm-1θmax = 26.2°, θmin = 3.7°
φ and ω scansh = 1117
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2007)
k = 45
Tmin = 0.769, Tmax = 1.000l = 820
2124 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)] = 0.039H-atom parameters constrained
wR(F2) = 0.104 w = 1/[σ2(Fo2) + (0.0678P)2 + 0.7978P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max = 0.001
1322 reflectionsΔρmax = 0.42 e Å3
145 parametersΔρmin = 0.35 e Å3
1 restraintAbsolute structure: Flack (1983), 242 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.57 (13)
Crystal data top
C14H10OSV = 1075.07 (14) Å3
Mr = 226.28Z = 4
Orthorhombic, Pna21Mo Kα radiation
a = 14.6208 (11) ŵ = 0.27 mm1
b = 4.3503 (3) ÅT = 110 K
c = 16.9023 (13) Å0.47 × 0.42 × 0.12 mm
Data collection top
Oxford Diffraction Gemini R CCD
diffractometer
1322 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2007)
1291 reflections with I > 2σ(I)
Tmin = 0.769, Tmax = 1.000Rint = 0.022
2124 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.039H-atom parameters constrained
wR(F2) = 0.104Δρmax = 0.42 e Å3
S = 1.06Δρmin = 0.35 e Å3
1322 reflectionsAbsolute structure: Flack (1983), 242 Friedel pairs
145 parametersAbsolute structure parameter: 0.57 (13)
1 restraint
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
S0.52142 (4)0.06772 (16)0.24929 (6)0.0178 (2)
O0.78147 (17)0.0883 (7)0.09651 (19)0.0321 (7)
C10.7100 (2)0.0006 (8)0.1263 (2)0.0200 (7)
C20.7074 (2)0.0905 (7)0.2121 (2)0.0180 (7)
C30.7902 (2)0.2143 (7)0.2405 (2)0.0227 (7)
H3A0.84230.21290.20700.027*
C40.7980 (2)0.3374 (9)0.3154 (2)0.0256 (8)
H4A0.85430.42370.33260.031*
C50.7227 (2)0.3339 (9)0.3654 (2)0.0244 (7)
H5A0.72760.41670.41730.029*
C60.6408 (2)0.2104 (7)0.3401 (2)0.0192 (7)
H6A0.58970.21000.37480.023*
C70.6316 (2)0.0853 (6)0.26388 (19)0.0161 (7)
C80.5289 (2)0.2607 (8)0.1555 (2)0.0207 (7)
H8A0.58050.40780.15690.025*
H8B0.47200.37960.14660.025*
C90.5423 (2)0.0449 (7)0.0884 (2)0.0170 (7)
C100.4704 (2)0.0389 (8)0.0388 (2)0.0209 (7)
H10A0.41100.04160.04800.025*
C110.4848 (3)0.2376 (9)0.0235 (2)0.0266 (8)
H11A0.43500.29610.05630.032*
C120.5718 (3)0.3529 (8)0.0386 (2)0.0261 (8)
H12A0.58140.48790.08200.031*
C130.6447 (2)0.2706 (8)0.0099 (2)0.0222 (7)
H13A0.70430.34760.00060.027*
C140.6299 (2)0.0741 (7)0.0741 (2)0.0187 (7)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S0.0114 (3)0.0242 (4)0.0177 (4)0.0023 (3)0.0028 (3)0.0015 (4)
O0.0181 (12)0.0470 (16)0.0312 (15)0.0089 (11)0.0049 (11)0.0110 (13)
C10.0157 (14)0.0217 (14)0.0226 (19)0.0006 (13)0.0051 (14)0.0056 (14)
C20.0163 (15)0.0174 (14)0.0203 (17)0.0046 (11)0.0009 (13)0.0016 (13)
C30.0113 (12)0.0297 (15)0.027 (2)0.0020 (12)0.0013 (15)0.0002 (17)
C40.0167 (15)0.0290 (18)0.031 (2)0.0024 (14)0.0047 (15)0.0004 (16)
C50.0257 (17)0.0275 (16)0.0201 (17)0.0011 (15)0.0046 (15)0.0026 (15)
C60.0176 (14)0.0205 (15)0.0196 (15)0.0019 (13)0.0039 (13)0.0006 (14)
C70.0142 (13)0.0141 (13)0.020 (2)0.0016 (11)0.0002 (12)0.0000 (11)
C80.0200 (14)0.0193 (16)0.0228 (19)0.0038 (12)0.0014 (13)0.0017 (14)
C90.0205 (14)0.0153 (15)0.0153 (17)0.0009 (12)0.0005 (13)0.0048 (12)
C100.0189 (15)0.0202 (16)0.0235 (19)0.0007 (13)0.0016 (13)0.0050 (14)
C110.0299 (18)0.0252 (17)0.0247 (19)0.0018 (14)0.0070 (15)0.0023 (16)
C120.0348 (18)0.0255 (17)0.0179 (16)0.0010 (16)0.0040 (15)0.0020 (14)
C130.0258 (16)0.0216 (16)0.0191 (16)0.0033 (13)0.0075 (14)0.0040 (14)
C140.0179 (15)0.0170 (14)0.0211 (17)0.0020 (12)0.0048 (14)0.0043 (13)
Geometric parameters (Å, º) top
S—C71.760 (3)C6—H6A0.95
S—C81.798 (4)C8—C91.485 (5)
O—C11.223 (4)C8—H8A0.99
C1—C141.500 (5)C8—H8B0.99
C1—C21.503 (5)C9—C101.394 (5)
C2—C31.409 (4)C9—C141.402 (5)
C2—C71.413 (4)C10—C111.378 (6)
C3—C41.379 (5)C10—H10A0.95
C3—H3A0.95C11—C121.391 (5)
C4—C51.388 (5)C11—H11A0.95
C4—H4A0.95C12—C131.392 (5)
C5—C61.381 (5)C12—H12A0.95
C5—H5A0.95C13—C141.398 (5)
C6—C71.404 (4)C13—H13A0.95
C7—S—C8104.17 (15)C9—C8—H8A109.1
O—C1—C14119.5 (3)S—C8—H8A109.1
O—C1—C2120.1 (3)C9—C8—H8B109.1
C14—C1—C2119.5 (3)S—C8—H8B109.1
C3—C2—C7118.0 (3)H8A—C8—H8B107.8
C3—C2—C1114.0 (3)C10—C9—C14119.2 (3)
C7—C2—C1127.8 (3)C10—C9—C8121.6 (3)
C4—C3—C2122.2 (3)C14—C9—C8119.1 (3)
C4—C3—H3A118.9C11—C10—C9120.5 (3)
C2—C3—H3A118.9C11—C10—H10A119.7
C3—C4—C5119.3 (3)C9—C10—H10A119.7
C3—C4—H4A120.4C10—C11—C12120.4 (4)
C5—C4—H4A120.4C10—C11—H11A119.8
C6—C5—C4120.2 (3)C12—C11—H11A119.8
C6—C5—H5A119.9C11—C12—C13120.0 (3)
C4—C5—H5A119.9C11—C12—H12A120.0
C5—C6—C7121.3 (3)C13—C12—H12A120.0
C5—C6—H6A119.4C12—C13—C14119.7 (3)
C7—C6—H6A119.4C12—C13—H13A120.1
C6—C7—C2119.1 (3)C14—C13—H13A120.1
C6—C7—S111.3 (2)C13—C14—C9120.1 (3)
C2—C7—S129.6 (3)C13—C14—C1117.8 (3)
C9—C8—S112.7 (2)C9—C14—C1122.2 (3)
O—C1—C2—C331.1 (4)S—C8—C9—C10101.8 (3)
C14—C1—C2—C3137.8 (3)S—C8—C9—C1479.1 (3)
O—C1—C2—C7153.8 (3)C14—C9—C10—C110.3 (5)
C14—C1—C2—C737.3 (5)C8—C9—C10—C11179.4 (3)
C7—C2—C3—C42.1 (5)C9—C10—C11—C121.2 (5)
C1—C2—C3—C4173.4 (3)C10—C11—C12—C130.7 (6)
C2—C3—C4—C51.5 (5)C11—C12—C13—C140.6 (5)
C3—C4—C5—C60.5 (5)C12—C13—C14—C91.4 (5)
C4—C5—C6—C70.2 (5)C12—C13—C14—C1177.9 (3)
C5—C6—C7—C20.9 (5)C10—C9—C14—C131.0 (5)
C5—C6—C7—S177.7 (3)C8—C9—C14—C13178.1 (3)
C3—C2—C7—C61.8 (4)C10—C9—C14—C1178.4 (3)
C1—C2—C7—C6173.1 (3)C8—C9—C14—C12.5 (5)
C3—C2—C7—S176.6 (2)O—C1—C14—C1350.7 (4)
C1—C2—C7—S8.5 (5)C2—C1—C14—C13118.2 (4)
C8—S—C7—C6172.2 (2)O—C1—C14—C9129.9 (4)
C8—S—C7—C26.3 (3)C2—C1—C14—C961.1 (4)
C7—S—C8—C967.1 (3)

Experimental details

Crystal data
Chemical formulaC14H10OS
Mr226.28
Crystal system, space groupOrthorhombic, Pna21
Temperature (K)110
a, b, c (Å)14.6208 (11), 4.3503 (3), 16.9023 (13)
V3)1075.07 (14)
Z4
Radiation typeMo Kα
µ (mm1)0.27
Crystal size (mm)0.47 × 0.42 × 0.12
Data collection
DiffractometerOxford Diffraction Gemini R CCD
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2007)
Tmin, Tmax0.769, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
2124, 1322, 1291
Rint0.022
(sin θ/λ)max1)0.622
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.104, 1.06
No. of reflections1322
No. of parameters145
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.42, 0.35
Absolute structureFlack (1983), 242 Friedel pairs
Absolute structure parameter0.57 (13)

Computer programs: CrysAlis PRO (Oxford Diffraction, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and WebMOPro (Schmidt & Polik, 2007).

 

Acknowledgements

QNMHA thanks the University of Mysore for use of their research facilities. RJB acknowledges the NSF MRI program (grant No. CHE-0619278) for funds to purchase an X-ray diffractometer.

References

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