5-(Prop-2-yn­yl)-5H-dibenzo[b,f]azepine

S Yousuf; M Khan; S Fazal; M Butt; F Z Basha

doi:10.1107/S1600536812007866

. 2012 Mar 17;68(Pt 4):o1101. doi: 10.1107/S1600536812007866

5-(Prop-2-ynyl)-5H-dibenzo[b,f]azepine

S Yousuf ^a,^*, M Khan ^a, S Fazal ^a, M Butt ^a, F Z Basha ^a

PMCID: PMC3344052 PMID: 22589961

Abstract

The asymmetric unit of the title compound, C₁₇H₁₃N, contains two independent butterfly-shaped molecules. The seven-membered azepine rings both adopt a boat conformation. The dihedral angles between the benzene rings in the two molecules are 46.95 (11) and 52.21 (11)°.

Related literature

For the biological activities of iminostilbene, see: Kumar & Naik (2010 ▶); Balaure et al. (2009 ▶); Bhatt & Patel (2005 ▶); Fuenfschilling et al. (2005 ▶); Rosowsky et al. (2004 ▶); Brzozowski & Saczewski (2002 ▶); Kulkarni et al. (1991 ▶); Arya et al. (1977 ▶). For the crystal structures of the closely related compounds, see: Jayasankar et al. (2009 ▶); Nagaraj et al. (2005 ▶); Sadashiva et al. (2005 ▶).

Experimental

Crystal data

C₁₇H₁₃N
M _r = 231.28
Monoclinic,
a = 11.4406 (5) Å
b = 10.0256 (4) Å
c = 22.3155 (10) Å
β = 92.910 (1)°
V = 2556.26 (19) Å³
Z = 8
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 273 K
0.36 × 0.19 × 0.15 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000 ▶) T _min = 0.975, T _max = 0.990
14791 measured reflections
4760 independent reflections
2894 reflections with I > 2σ(I)
R _int = 0.031

Refinement

R[F ² > 2σ(F ²)] = 0.048
wR(F ²) = 0.129
S = 1.02
4760 reflections
333 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.13 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Data collection: SMART (Bruker, 2000 ▶); cell refinement: SAINT (Bruker, 2000 ▶); data reduction: SAINT; 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, PARST (Nardelli, 1995 ▶) and PLATON (Spek, 2009 ▶).

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536812007866/rz2705sup1.cif

e-68-o1101-sup1.cif^{(24.4KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812007866/rz2705Isup2.hkl

e-68-o1101-Isup2.hkl^{(233.2KB, hkl)}

Supplementary material file. DOI: 10.1107/S1600536812007866/rz2705Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

Iminostilbene (5H-dibenzo[b,f]azepine) was found to be a valuable intermediate in medicinal chemistry. It is also a basic nucleus of many anticonvulsant drugs including carbamazepine (Balaure et al., 2009), oxazepine (Fuenfschilling et al., 2005) and imipramine (Bhatt & Patel, 2005). The structural analogue of iminostilbene showed a wide range of biological activities such as antioxidant (Kumar & Naik, 2010), antihypertensive (Arya et al., 1977), antitumor (Brzozowski & Saczewski, 2002), pesticidal (Kulkarni et al., 1991), and DHFR inhibitory activity (Rosowsky et al., 2004). The title compound was synthesized as part of our ongoing research on the synthesis of new derivatives of iminostilbene as potential anti-epileptic agents with more efficacy, low toxicity and no side effects as compared to the available drugs (Sadashiva et al., 2005).

The structure of the title compound contains two independent molecules in the asymmetric unit (Fig. 1). Each molecule is consists of two phenyl rings fused to a seven-membered azepine ring adopting a boat conformation. The overall shape of each molecule is butterfly-like. The dihedral angles between the phenyl rings are 46.95 (11) and 52.21 (11)° for C1–C5/C14, C6–C11 and C18–C22/C31, C23–C28, respectively. The bond lengths and angles are found to be similar to those observed in other structurally related compounds (Jayasankar et al., 2009; Nagaraj et al., 2005; Sadashiva et al., 2005). The crystal packing (Fig. 2) is enforced only by van der Waals forces.

Experimental

To the stirred solution of iminostilbene (0.2921 g, 1.5 mmol) in DMF (3.0 mL), propargyl bromide (0.41 ml, 4.5 mmol) and potassium carbonate (0.418 ml, 3.02 mmol) were added and refluxed for 15 h at 90°C. After completion of the reaction reaction as judged by TLC, the crude mixture was adsorbed on silica and purified by column chromatography (eluent: n-hexane:ethyl acetate, 9.5:0.5 v/v) to obtain the title compound in 77% yield. Recrystallization by slow evaporation of a methanol solution afforded yellow crystals suitable for single-crystal X-ray diffraction studies. Iminostilbene and propargyl bromide were purchased from Alfa Acer and Aldrich, respectively.