6,11-Dihydro­dibenz[b,e]oxepin-11-one

Jasinski, J.P.; Hakim AL-arique, Q.N.M.; Butcher, R.J.; Yathirajan, H.S.; Narayana, B.

doi:10.1107/S1600536809053409

organic compounds

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ISSN: 2056-9890

Volume 66| Part 1| January 2010| Pages o159-o160

doi:10.1107/S1600536809053409

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6,11-Dihydrodibenz[b,e]oxepin-11-one

Jerry P. Jasinski,^a ^* Q. N. M. Hakim Al-arique,^b Ray J. Butcher,^c H. S. Yathirajan ^b and B. Narayana ^d

^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 5 December 2009; accepted 11 December 2009; online 16 December 2009)

In the title compound, C₁₄H₁₀O₂, the seven-membered oxepine ring adopts a twist-boat conformation with a dihedral angle between the mean planes of the two fused benzene rings of 42.0 (1)°. In the crystal, molecules are linked into chains propagating along the c axis by intermolecular C—H⋯O hydrogen bonds and the chains are arranged in layers parallel to (100).

Related literature

The dibenz[b,e]oxepin nucleus constitutes the fundamental structure of many products with biological activity, see: Kumazawa et al. (1994 ). For dibenzo[c,e]thiepine derivatives and their chiroptical properties, see: Truce et al. (1956 ); Tomascovic et al. (2000 ). For comparative NMR and IR spectral, X-ray structural and theoretical studies of eight related 6-arylidenedibenzo[b,e]thiepin-11-one-5,5-dioxides, see: Kolehmainen et al. (2007 ). For related structures, see: Bandoli & Nicolini (1982 ); Blaton et al. (1995 ); Ieawsuwan et al. (2006 ); Linden et al. (2004 ); Roszak et al. (1996 ); Yoshinari & Konno (2009 ); Zhang et al. (2008 ,2008a ). For DFT calculations, see: Hehre et al. (1986 ); Schmidt & Polik (2007 ). For the GAUSSIAN03 program package, see: Frisch et al. (2004 ). For a description of the Cambridge Structural Database, see: Allen (2002 ).

Experimental

Crystal data

C₁₄H₁₀O₂
M_r = 210.22
Monoclinic, C c
a = 16.5065 (18) Å
b = 4.0806 (7) Å
c = 15.0392 (17) Å
β = 93.654 (10)°
V = 1010.9 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 110 K
0.53 × 0.27 × 0.23 mm

Data collection

Oxford Diffraction Gemini R CCD diffractometer
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007 $[Oxford Diffraction (2007). CrysAlis PRO) and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ) T_min = 0.864, T_max = 1.000
1472 measured reflections
968 independent reflections
953 reflections with I > 2σ(I)
R_int = 0.019

Refinement

R[F² > 2σ(F²)] = 0.040
wR(F²) = 0.108
S = 1.06
968 reflections
145 parameters
2 restraints
H-atom parameters constrained
Δρ_max = 0.24 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C10—H10A⋯O1ⁱ	0.95	2.57	3.380 (3)	143
Symmetry code: (i) $[x, -y+1, z-{\script{1\over 2}}]$ .

Data collection: CrysAlis PRO (Oxford Diffraction, 2007 $[Oxford Diffraction (2007). CrysAlis PRO) and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809053409/ci2982sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809053409/ci2982Isup2.hkl

checkCIF report

Comment top

The title compound is used as an intermediate for the synthesis of doxepin, which is a psychotropic agent with tricyclic antidepressant and anxiolytic properties. Doxepin is a tricyclic compound and displays a range of pharmacological actions including maintaining adrenergic innervation. Its mechanism of action is not fully understood, but it appears to block re-uptake of monoaminergic neurotransmitters into presynaptic terminals. It also possesses anticholinergic activity and modulates antagonism of histamine H(1)- and H(2)-receptors. The dibenz[b,e]oxepin nucleus constitutes the fundamental structure of many products with biological activity (Kumazawa et al., 1994). The dibenzo[c,e]thiepine derivatives (Truce et al., 1956) exhibit remarkable chiroptical properties (Tomascovic et al., 2000). The comparative NMR and IR spectral, X-ray structural and theoretical studies of eight related 6-arylidenedibenzo[b,e]thiepin-11-one-5,5-dioxides have been reported (Kolehmainen et al., 2007). In view of the importance of oxepines, this paper reports the crystal structure of the title compound.

The seven-membered oxepin ring adopts a twist-boat conformation with the dihedral angle between the mean planes of the two fused benzene rings measuring 42.0 (1)° (Fig. 1). This conformation is assisted by sp³ hybridization of atoms C8 and O2 within the ring. The ketone oxygen atom (O1) lies in an equatorial position from the ring on opposite sides of the C8 and O2 atoms (C3—C2—C1—O1 = -19.1 (4)° and C13—C14—C1—O1 = 35.3 (4)°). Bond lengths and angles are all within expected ranges (Allen, 2002). The molecules are linked into chains propagating along the c-axis by C10–H10A···O1 intermolecular hydrogen bonds and the chains are arranged in layers parallel to the (100) (Fig. 2).

After a density functional theory (DFT) computational calculation at the 6–31-G(d) level (Hehre et al., 1986; Schmidt & Polik, 2007) with the GAUSSIAN03 program package (Frisch et al., 2004), the angle between the mean planes of the two benzene rings becomes 34.8 (2)°, a decrease of 7.2 (2)°. The C3—C2—C1—O1 and C13—C14—C1—O1 torsion angles become -8.7 (5)°) and 26.1 (5)°, a decrease of 10.3 (5)° and 9.1 (8)°, respectively. This suggests that the crystal packing is influenced by the weak C—H···O intermolecular hydrogen bonding interactions.

Related literature top

The dibenz[b,e]oxepin nucleus constitutes the fundamental structure of many products with biological activity, see: Kumazawa et al. (1994). For dibenzo[c,e]thiepine derivatives and their chiroptical properties, see: Truce et al. (1956); Tomascovic et al. (2000). For comparative NMR and IR spectral, X-ray structural and theoretical studies of eight related 6-arylidenedibenzo[b,e]thiepin-11-one-5,5-dioxides, see: Kolehmainen et al. (2007). For related structures, see: Bandoli & Nicolini (1982); Blaton et al. (1995); Ieawsuwan et al. (2006); Linden et al. (2004); Roszak et al. (1996); Yoshinari & Konno (2009); Zhang et al. (2008,2008a). For DFT calculations, see: Hehre et al. (1986); Schmidt & Polik (2007). For the GAUSSIAN03 program package, see: 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. 327–329 K) were obtained by slow evaporation from a methanol solution.

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).

Figures top

	Fig. 1. Molecular structure of the title compound, showing atom-labeling scheme and 50% probability displacement ellipsoids.
	Fig. 2. Packing diagram of the title compound, viewed down the a axis. Dashed lines indicate weak intermolecular C—H···O hydrogen bonds.

6,11-Dihydrodibenz[b,e]oxepin-11-one top

Crystal data top

C₁₄H₁₀O₂	F(000) = 440
M_r = 210.22	D_x = 1.381 Mg m⁻³
Monoclinic, Cc	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2yc	Cell parameters from 1157 reflections
a = 16.5065 (18) Å	θ = 6.0–73.7°
b = 4.0806 (7) Å	µ = 0.09 mm⁻¹
c = 15.0392 (17) Å	T = 110 K
β = 93.654 (10)°	Thick needle, colorless
V = 1010.9 (2) Å³	0.53 × 0.27 × 0.23 mm
Z = 4

Data collection top

Oxford Diffraction Gemini R CCD diffractometer	968 independent reflections
Radiation source: fine-focus sealed tube	953 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.019
Detector resolution: 10.5081 pixels mm^-1	θ_max = 26.3°, θ_min = 3.8°
ϕ and ω scans	h = −15→20
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007)	k = −4→2
T_min = 0.864, T_max = 1.000	l = −18→17
1472 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.108	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.0835P)² + 0.4174P] where P = (F_o² + 2F_c²)/3
968 reflections	(Δ/σ)_max = 0.001
145 parameters	Δρ_max = 0.24 e Å⁻³
2 restraints	Δρ_min = −0.24 e Å⁻³

Crystal data top

C₁₄H₁₀O₂	V = 1010.9 (2) Å³
M_r = 210.22	Z = 4
Monoclinic, Cc	Mo Kα radiation
a = 16.5065 (18) Å	µ = 0.09 mm⁻¹
b = 4.0806 (7) Å	T = 110 K
c = 15.0392 (17) Å	0.53 × 0.27 × 0.23 mm
β = 93.654 (10)°

Data collection top

Oxford Diffraction Gemini R CCD diffractometer	968 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007)	953 reflections with I > 2σ(I)
T_min = 0.864, T_max = 1.000	R_int = 0.019
1472 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.040	2 restraints
wR(F²) = 0.108	H-atom parameters constrained
S = 1.06	Δρ_max = 0.24 e Å⁻³
968 reflections	Δρ_min = −0.24 e Å⁻³
145 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.

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

	x	y	z	U_iso*/U_eq
O1	0.45613 (12)	0.6693 (6)	0.53696 (13)	0.0390 (6)
O2	0.63969 (10)	0.7966 (4)	0.34730 (11)	0.0255 (4)
C1	0.49884 (15)	0.7517 (7)	0.47743 (17)	0.0252 (5)
C2	0.58727 (16)	0.8141 (6)	0.49769 (17)	0.0239 (5)
C3	0.61004 (16)	0.8726 (7)	0.58847 (17)	0.0293 (6)
H3A	0.5707	0.8400	0.6311	0.035*
C4	0.68631 (18)	0.9743 (8)	0.61780 (19)	0.0343 (7)
H4A	0.6997	1.0074	0.6795	0.041*
C5	0.74432 (17)	1.0287 (7)	0.5551 (2)	0.0333 (6)
H5A	0.7970	1.1056	0.5740	0.040*
C6	0.72459 (16)	0.9703 (7)	0.46615 (19)	0.0285 (6)
H6A	0.7640	1.0079	0.4240	0.034*
C7	0.64779 (15)	0.8571 (6)	0.43686 (17)	0.0236 (5)
C8	0.57772 (16)	0.5685 (7)	0.31616 (18)	0.0275 (6)
H8A	0.5774	0.3803	0.3577	0.033*
H8B	0.5906	0.4841	0.2570	0.033*
C9	0.49518 (16)	0.7233 (6)	0.30917 (17)	0.0236 (5)
C10	0.45306 (17)	0.7704 (7)	0.22715 (18)	0.0280 (6)
H10A	0.4768	0.7045	0.1741	0.034*
C11	0.37673 (18)	0.9126 (8)	0.22225 (18)	0.0312 (6)
H11A	0.3483	0.9431	0.1659	0.037*
C12	0.34162 (17)	1.0107 (8)	0.29936 (19)	0.0311 (6)
H12A	0.2898	1.1129	0.2958	0.037*
C13	0.38244 (15)	0.9588 (7)	0.38147 (18)	0.0275 (6)
H13A	0.3579	1.0205	0.4344	0.033*
C14	0.45922 (15)	0.8167 (6)	0.38669 (17)	0.0227 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0282 (10)	0.0601 (15)	0.0289 (10)	−0.0057 (10)	0.0042 (8)	0.0139 (10)
O2	0.0203 (9)	0.0282 (9)	0.0285 (10)	0.0004 (8)	0.0056 (7)	−0.0020 (8)
C1	0.0239 (12)	0.0259 (12)	0.0261 (12)	−0.0002 (10)	0.0039 (10)	0.0027 (10)
C2	0.0239 (12)	0.0197 (12)	0.0280 (13)	0.0021 (9)	0.0012 (9)	0.0032 (9)
C3	0.0316 (14)	0.0302 (14)	0.0261 (12)	0.0035 (11)	0.0027 (10)	0.0044 (11)
C4	0.0386 (15)	0.0351 (16)	0.0282 (14)	0.0019 (12)	−0.0067 (12)	−0.0022 (12)
C5	0.0247 (12)	0.0277 (14)	0.0463 (17)	0.0002 (11)	−0.0073 (11)	−0.0028 (12)
C6	0.0226 (11)	0.0231 (13)	0.0401 (14)	0.0010 (9)	0.0035 (10)	−0.0004 (11)
C7	0.0215 (11)	0.0182 (12)	0.0309 (13)	0.0038 (9)	0.0005 (9)	0.0028 (10)
C8	0.0278 (13)	0.0252 (14)	0.0295 (12)	0.0026 (10)	0.0010 (10)	−0.0054 (10)
C9	0.0240 (11)	0.0181 (12)	0.0288 (13)	−0.0041 (9)	0.0018 (9)	−0.0004 (9)
C10	0.0314 (13)	0.0245 (13)	0.0277 (12)	−0.0052 (10)	−0.0015 (10)	−0.0019 (10)
C11	0.0331 (13)	0.0310 (15)	0.0285 (13)	−0.0042 (11)	−0.0066 (10)	0.0034 (11)
C12	0.0218 (11)	0.0300 (14)	0.0410 (15)	0.0013 (9)	−0.0034 (10)	0.0061 (11)
C13	0.0237 (12)	0.0290 (14)	0.0300 (12)	−0.0013 (10)	0.0042 (9)	0.0015 (10)
C14	0.0215 (10)	0.0178 (13)	0.0286 (13)	−0.0028 (9)	−0.0003 (9)	0.0037 (9)

Geometric parameters (Å, º) top

O1—C1	1.221 (3)	C6—H6A	0.95
O2—C7	1.367 (3)	C8—C9	1.499 (3)
O2—C8	1.439 (3)	C8—H8A	0.99
C1—C2	1.494 (3)	C8—H8B	0.99
C1—C14	1.499 (3)	C9—C10	1.390 (4)
C2—C7	1.408 (3)	C9—C14	1.395 (4)
C2—C3	1.413 (4)	C10—C11	1.385 (4)
C3—C4	1.372 (4)	C10—H10A	0.95
C3—H3A	0.95	C11—C12	1.388 (4)
C4—C5	1.403 (4)	C11—H11A	0.95
C4—H4A	0.95	C12—C13	1.385 (4)
C5—C6	1.378 (4)	C12—H12A	0.95
C5—H5A	0.95	C13—C14	1.391 (4)
C6—C7	1.394 (3)	C13—H13A	0.95

C7—O2—C8	117.40 (19)	O2—C8—H8A	109.2
O1—C1—C2	120.0 (2)	C9—C8—H8A	109.2
O1—C1—C14	118.5 (2)	O2—C8—H8B	109.2
C2—C1—C14	121.3 (2)	C9—C8—H8B	109.2
C7—C2—C3	116.8 (2)	H8A—C8—H8B	107.9
C7—C2—C1	127.8 (2)	C10—C9—C14	119.2 (3)
C3—C2—C1	115.0 (2)	C10—C9—C8	121.4 (2)
C4—C3—C2	123.0 (3)	C14—C9—C8	119.3 (2)
C4—C3—H3A	118.5	C11—C10—C9	120.5 (3)
C2—C3—H3A	118.5	C11—C10—H10A	119.8
C3—C4—C5	118.9 (3)	C9—C10—H10A	119.8
C3—C4—H4A	120.5	C10—C11—C12	120.2 (2)
C5—C4—H4A	120.5	C10—C11—H11A	119.9
C6—C5—C4	119.7 (3)	C12—C11—H11A	119.9
C6—C5—H5A	120.1	C13—C12—C11	119.7 (3)
C4—C5—H5A	120.1	C13—C12—H12A	120.1
C5—C6—C7	121.2 (3)	C11—C12—H12A	120.1
C5—C6—H6A	119.4	C12—C13—C14	120.2 (2)
C7—C6—H6A	119.4	C12—C13—H13A	119.9
O2—C7—C6	113.6 (2)	C14—C13—H13A	119.9
O2—C7—C2	126.1 (2)	C9—C14—C13	120.1 (2)
C6—C7—C2	120.3 (2)	C9—C14—C1	121.9 (2)
O2—C8—C9	112.0 (2)	C13—C14—C1	117.9 (2)

O1—C1—C2—C7	168.6 (3)	O2—C8—C9—C10	113.0 (3)
C14—C1—C2—C7	−16.9 (4)	O2—C8—C9—C14	−68.2 (3)
O1—C1—C2—C3	−19.1 (4)	C14—C9—C10—C11	0.9 (4)
C14—C1—C2—C3	155.4 (2)	C8—C9—C10—C11	179.7 (3)
C7—C2—C3—C4	1.6 (4)	C9—C10—C11—C12	0.2 (4)
C1—C2—C3—C4	−171.6 (3)	C10—C11—C12—C13	−1.5 (4)
C2—C3—C4—C5	1.1 (5)	C11—C12—C13—C14	1.6 (4)
C3—C4—C5—C6	−1.9 (4)	C10—C9—C14—C13	−0.8 (4)
C4—C5—C6—C7	−0.1 (4)	C8—C9—C14—C13	−179.6 (2)
C8—O2—C7—C6	156.5 (2)	C10—C9—C14—C1	175.7 (2)
C8—O2—C7—C2	−23.3 (3)	C8—C9—C14—C1	−3.1 (4)
C5—C6—C7—O2	−176.9 (2)	C12—C13—C14—C9	−0.5 (4)
C5—C6—C7—C2	2.9 (4)	C12—C13—C14—C1	−177.1 (2)
C3—C2—C7—O2	176.3 (2)	O1—C1—C14—C9	−141.2 (3)
C1—C2—C7—O2	−11.6 (4)	C2—C1—C14—C9	44.2 (4)
C3—C2—C7—C6	−3.5 (4)	O1—C1—C14—C13	35.3 (4)
C1—C2—C7—C6	168.6 (3)	C2—C1—C14—C13	−139.2 (3)
C7—O2—C8—C9	79.7 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10A···O1ⁱ	0.95	2.57	3.380 (3)	143

Symmetry code: (i) x, −y+1, z−1/2.

Experimental details

Crystal data
Chemical formula	C₁₄H₁₀O₂
M_r	210.22
Crystal system, space group	Monoclinic, Cc
Temperature (K)	110
a, b, c (Å)	16.5065 (18), 4.0806 (7), 15.0392 (17)
β (°)	93.654 (10)
V (Å³)	1010.9 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.53 × 0.27 × 0.23

Data collection
Diffractometer	Oxford Diffraction Gemini R CCD diffractometer
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2007)
T_min, T_max	0.864, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	1472, 968, 953
R_int	0.019
(sin θ/λ)_max (Å⁻¹)	0.623

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.040, 0.108, 1.06
No. of reflections	968
No. of parameters	145
No. of restraints	2
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.24, −0.24

Computer programs: CrysAlis PRO (Oxford Diffraction, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10A···O1ⁱ	0.95	2.57	3.380 (3)	143

Symmetry code: (i) x, −y+1, z−1/2.

Acknowledgements

QNMHA thanks the University of Mysore for use of its 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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