(E)-2-Phenyl-4-styryl-2,3-di­hydro-1H-1,5-benzodiazepine hemihydrate

Loughzail, M.; Adardour, M.; Dahaoui, S.; Baouid, A.

doi:10.1107/S2414314617010707

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 2| Part 7| July 2017| x171070

https://doi.org/10.1107/S2414314617010707

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(E)-2-Phenyl-4-styryl-2,3-dihydro-1H-1,5-benzodiazepine hemihydrate

Mohamed Loughzail,^a ^* Mohamed Adardour,^a Slimane Dahaoui ^b and Abdesselam Baouid ^a

^aLaboratoire de Chimie Moléculaire, Département de Chimie, Faculté des Sciences Semlalia, BP 2390, Université Cadi Ayyad, 40001 Marrakech, Morocco, and ^bCristallographie, Résonance, Magnétique et Mod\'lisation (CRM2), Université Henri Poincaré, Nancy 1, Faculté des Sciences, BP 70239, 54506 Vandoeuvre le`s Nancy CEDEX, France
^*Correspondence e-mail: loughzail@gmail.com

Edited by K. Fejfarova, Institute of Biotechnology CAS, Czech Republic (Received 11 July 2017; accepted 19 July 2017; online 25 July 2017)

The unit cell contains eight molecules of the title compound, with half a water molecule per main molecule, C₂₃H₂₀N₂·0.5H₂O. The seven-membered diazepine ring adopts a twist-boat conformation and makes dihedral angles of 85.08 (7) and 32.79 (7)° with the phenyl and styryl substituents, respectively. In the crystal, the organic molecules are linked by C—H⋯N hydrogen bonds into chains running along the b-axis direction. The water molecule, located on a twofold rotation axis, forms hydrogen bridges, connecting two adjacent chains.

Keywords: crystal structure; 1,5-benzodiazepine; dichalcone; hydrogen bonding.

CCDC reference: 1563375

Structure description

Benzodiazepines are heterocyclic compounds that are considered to be `privileged structures' since they possess a wide range of biological activities. 1,5-Benzodiazepines have found applications in medicine, being one of the most important classes of the therapeutic agents with widespread biological activities. They are commonly used as anti-inflammatory (Bhat & Kumar, 2016 ), antioxidant (Patil et al., 2015 ), anticancer (Chen et al., 2014 ), antimicrobial (El-Gaml et al., 2014 ) and antiviral (Nyanguile et al., 2008 ) substances and constitute the backbones of several marketed drugs. 1,5-Benzodiazepines are generally synthesized by the condensation of o-phenylenediamine with α,β-unsaturated carbonyl compounds (Claramunt et al., 2006 ), β-haloketones (Ilango et al., 2013 ), or with ketones using acidic catalysts (Jeganathan & Pitchumani, 2014 ) or the microwave irradiation technique, which is critical to enhance the condensation process (Chikhale & Khedekar, 2013 ). We report here the synthesis and characterization of a new 1,5-benzodiazepine derivative.

The molecular structure of the title compound is illustrated in Fig. 1. In the molecule, which adopts an approximate U shape, the seven-membered diazepine ring displays a twist-boat conformation as indicated by the total puckering amplitude Q_T = 0.9442 (19)°, and spherical polar angle θ2 = 79.23 (11)°; φ2= 118.15 (13)° and φ3 = −104.5 (7)°. The benzodiazepine ring system makes dihedral angles of 85.08 (7) and 32.79 (7)° with the phenyl and styryl substituents, respectively.

Figure 1
The molecular structure of the title compound, with the atom labelling. Displacement ellipsoids are drawn at the 30% probability level.

In the crystal, the organic molecules are linked by C11—H11⋯N1 hydrogen bonds (Table 1, Fig. 2) into chains running along the b-axis direction. The water molecule, located on a twofold rotation axis, forms hydrogen bridges [N1⋯O01⋯N1( $[{1\over 2}]$ − x, y, −z); Fig. 3], connecting two adjacent chains.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O01—H01⋯N1	0.92 (3)	2.01 (3)	2.9300 (19)	174 (3)
C11—H11⋯N1ⁱ	0.95	2.51	3.426 (3)	161
Symmetry code: (i) x, y+1, z.

Figure 2
A view of the chains formed by C11—H11⋯N1 hydrogen bonds (Table 1

) and linked by N1⋯O01⋯N1 bridges.

Figure 3
Overall packing of the title compound, showing the N1—O01—N1 bridges.

Synthesis and crystallization

To a solution of 1,7-diphenylhepta-1,6-diene-3,5-dione (0.1 mol) in ethanol (30 ml) a few drops of triethylamine and 1,2-diaminobenzene (0.1 mol) were added. The mixture was heated under reflux for 12 h. The solvent was evaporated. The title compound was isolated by column chromatography on silica gel using hexane/ethyl acetate as eluent. The solid product was recrystallized in ethyl acetate to give crystals of the title compound.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₂₃H₂₀N₂·0.5H₂O
M_r	333.42
Crystal system, space group	Monoclinic, I2/a
Temperature (K)	100
a, b, c (Å)	22.1001 (8), 6.7624 (2), 24.5714 (7)
β (°)	104.835 (3)
V (Å³)	3549.8 (2)
Z	8
Radiation type	Cu Kα
μ (mm⁻¹)	0.58
Crystal size (mm)	0.21 × 0.16 × 0.04

Data collection
Diffractometer	Bruker X8 APEX
Absorption correction	Multi-scan (SADABS; Bruker, 2009 )
No. of measured, independent and observed [I > 2σ(I)] reflections	31210, 3649, 2831
R_int	0.148
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.058, 0.172, 1.07
No. of reflections	3649
No. of parameters	240
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.30
Computer programs: APEX2 and SAINT (Bruker, 2009), SHELXS2014(Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), ORTEP-3 for Windows (Farrugia, 2012 ) and Mercury (Macrae et al., 2008 ).

Structural data

CCDC reference: 1563375

Crystal structure: contains datablocks I, block. DOI: https://doi.org/10.1107/S2414314617010707/ff4018sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617010707/ff4018Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS2014(Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015).

(E)-2-Phenyl-4-styryl-2,3-dihydro-1H-1,5-benzodiazepine hemihydrate top

Crystal data top

C₂₃H₂₀N₂·0.5H₂O	F(000) = 1416
M_r = 333.42	D_x = 1.248 Mg m⁻³
Monoclinic, I2/a	Cu Kα radiation, λ = 1.54184 Å
a = 22.1001 (8) Å	Cell parameters from 3649 reflections
b = 6.7624 (2) Å	θ = 3.7–74.5°
c = 24.5714 (7) Å	µ = 0.58 mm⁻¹
β = 104.835 (3)°	T = 100 K
V = 3549.8 (2) Å³	Plate, colourless
Z = 8	0.21 × 0.16 × 0.04 mm

Data collection top

Bruker X8 APEX diffractometer	2831 reflections with I > 2σ(I)
Radiation source: fine-focus sealed X-ray tube	R_int = 0.148
φ and ω scans	θ_max = 74.5°, θ_min = 3.7°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −27→27
	k = −8→8
31210 measured reflections	l = −30→30
3649 independent reflections

Refinement top

Refinement on F²	Hydrogen site location: mixed
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F² > 2σ(F²)] = 0.058	w = 1/[σ²(F_o²) + (0.0998P)² + 0.8126P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.172	(Δ/σ)_max < 0.001
S = 1.07	Δρ_max = 0.25 e Å⁻³
3649 reflections	Δρ_min = −0.30 e Å⁻³
240 parameters	Extinction correction: SHELXL2014 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.00032 (11)

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. All H atoms attached to C atoms were fixed geometrically and treated as riding with C—H = 0.99 Å (methylene), 0.98 Å (methyl), 1.0Å (methine) with U_iso(H) = 1.2U_eq(CH and CH₂). The coordinates of H atoms attached to N atoms were freely refined with U_iso(H) = 1.2U_eq(N) and the H attached to hydroxyl O atoms were fixed geometrically and treated as riding with O—H = 0.84Å and U_iso(H) = 1.5U_eq(O).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O01	0.250000	0.4867 (3)	0.000000	0.0395 (5)
H	0.3281 (13)	0.996 (4)	0.2434 (12)	0.037 (7)*
H01	0.2594 (15)	0.572 (5)	0.0303 (12)	0.051 (8)*
C16	0.20259 (9)	0.9411 (3)	0.04598 (7)	0.0244 (4)
H16	0.184023	0.819984	0.030619	0.029*
N2	0.31472 (8)	0.9651 (2)	0.20337 (6)	0.0282 (4)
N1	0.28863 (8)	0.7563 (2)	0.09599 (6)	0.0249 (4)
C18	0.10669 (9)	1.1185 (3)	−0.00793 (6)	0.0240 (4)
C17	0.16963 (9)	1.1077 (3)	0.03003 (7)	0.0249 (4)
H17	0.188813	1.228920	0.044640	0.030*
C7	0.26467 (9)	0.9315 (3)	0.08503 (6)	0.0227 (4)
C6	0.34457 (9)	0.7303 (3)	0.13831 (7)	0.0231 (4)
C5	0.38511 (10)	0.5796 (3)	0.13048 (7)	0.0249 (4)
H5	0.375753	0.509354	0.095850	0.030*
C10	0.23119 (9)	1.2139 (3)	0.17243 (6)	0.0234 (4)
C21	−0.01405 (11)	1.1536 (3)	−0.07978 (8)	0.0341 (5)
H21	−0.054992	1.165117	−0.103952	0.041*
C1	0.35798 (9)	0.8318 (3)	0.19049 (7)	0.0252 (4)
C9	0.29638 (9)	1.1477 (3)	0.17111 (7)	0.0236 (4)
H9	0.326737	1.254179	0.188115	0.028*
C8	0.29998 (9)	1.1139 (3)	0.11003 (7)	0.0235 (4)
H8A	0.282325	1.230251	0.086914	0.028*
H8B	0.344362	1.100613	0.109275	0.028*
C2	0.41197 (10)	0.7797 (3)	0.23157 (7)	0.0288 (4)
H2	0.421618	0.847780	0.266563	0.035*
C11	0.21281 (10)	1.4043 (3)	0.15406 (7)	0.0283 (4)
H11	0.242354	1.491690	0.144851	0.034*
C4	0.43838 (10)	0.5304 (3)	0.17179 (8)	0.0280 (4)
H4	0.465374	0.428633	0.165373	0.034*
C23	0.07520 (10)	1.2995 (3)	−0.01512 (7)	0.0287 (4)
H23	0.094978	1.412296	0.004770	0.034*
C12	0.15186 (11)	1.4688 (3)	0.14894 (8)	0.0324 (4)
H12	0.139662	1.598047	0.135302	0.039*
C15	0.18828 (10)	1.0901 (3)	0.18831 (7)	0.0271 (4)
H15	0.200434	0.960834	0.201990	0.033*
C22	0.01555 (11)	1.3179 (3)	−0.05075 (8)	0.0321 (4)
H22	−0.004983	1.442502	−0.055280	0.039*
C3	0.45205 (10)	0.6315 (3)	0.22288 (8)	0.0293 (4)
H3	0.488507	0.599417	0.251574	0.035*
C19	0.07606 (10)	0.9550 (3)	−0.03779 (7)	0.0294 (4)
H19	0.096421	0.830136	−0.033653	0.035*
C14	0.12768 (10)	1.1559 (3)	0.18410 (8)	0.0329 (5)
H14	0.098747	1.071108	0.195262	0.039*
C13	0.10878 (10)	1.3435 (3)	0.16385 (8)	0.0344 (5)
H13	0.066951	1.385892	0.160215	0.041*
C20	0.01653 (11)	0.9730 (3)	−0.07325 (8)	0.0357 (5)
H20	−0.003486	0.860635	−0.093225	0.043*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O01	0.0638 (16)	0.0241 (9)	0.0237 (9)	0.000	−0.0016 (9)	0.000
C16	0.0288 (10)	0.0296 (9)	0.0128 (6)	−0.0014 (7)	0.0019 (6)	−0.0005 (6)
N2	0.0342 (9)	0.0366 (8)	0.0120 (6)	0.0074 (7)	0.0028 (6)	0.0019 (6)
N1	0.0291 (9)	0.0289 (8)	0.0146 (6)	−0.0020 (6)	0.0014 (6)	0.0009 (5)
C18	0.0281 (10)	0.0324 (9)	0.0113 (7)	−0.0001 (7)	0.0045 (6)	0.0003 (6)
C17	0.0315 (10)	0.0289 (8)	0.0136 (7)	−0.0005 (7)	0.0044 (7)	−0.0003 (6)
C7	0.0284 (10)	0.0280 (8)	0.0116 (7)	−0.0021 (7)	0.0047 (6)	0.0002 (6)
C6	0.0255 (9)	0.0258 (8)	0.0156 (7)	−0.0029 (7)	0.0005 (6)	0.0016 (6)
C5	0.0298 (10)	0.0247 (8)	0.0189 (7)	−0.0023 (7)	0.0041 (7)	−0.0003 (6)
C10	0.0283 (9)	0.0289 (8)	0.0113 (6)	−0.0018 (7)	0.0019 (6)	−0.0037 (6)
C21	0.0316 (11)	0.0427 (11)	0.0227 (8)	0.0045 (9)	−0.0026 (7)	−0.0001 (7)
C1	0.0294 (10)	0.0285 (8)	0.0166 (7)	0.0008 (7)	0.0040 (7)	0.0022 (6)
C9	0.0267 (10)	0.0278 (9)	0.0144 (7)	−0.0011 (7)	0.0019 (6)	−0.0009 (6)
C8	0.0286 (10)	0.0269 (8)	0.0144 (7)	−0.0002 (7)	0.0043 (6)	0.0014 (6)
C2	0.0314 (10)	0.0343 (9)	0.0162 (7)	0.0021 (8)	−0.0021 (7)	−0.0005 (7)
C11	0.0354 (11)	0.0304 (9)	0.0183 (7)	0.0005 (8)	0.0056 (7)	−0.0001 (6)
C4	0.0286 (10)	0.0288 (9)	0.0261 (8)	0.0027 (7)	0.0062 (7)	0.0022 (7)
C23	0.0365 (11)	0.0309 (9)	0.0171 (7)	−0.0006 (8)	0.0042 (7)	−0.0004 (6)
C12	0.0372 (11)	0.0368 (10)	0.0202 (8)	0.0106 (9)	0.0022 (7)	−0.0026 (7)
C15	0.0322 (10)	0.0307 (9)	0.0174 (7)	−0.0034 (8)	0.0047 (7)	−0.0022 (6)
C22	0.0362 (11)	0.0355 (10)	0.0214 (8)	0.0064 (8)	0.0015 (8)	0.0026 (7)
C3	0.0276 (10)	0.0344 (10)	0.0222 (8)	0.0013 (8)	−0.0007 (7)	0.0021 (7)
C19	0.0307 (10)	0.0329 (9)	0.0205 (8)	0.0023 (8)	−0.0007 (7)	−0.0036 (7)
C14	0.0313 (11)	0.0430 (11)	0.0248 (8)	−0.0082 (8)	0.0078 (8)	−0.0098 (8)
C13	0.0287 (11)	0.0474 (12)	0.0247 (8)	0.0044 (9)	0.0023 (7)	−0.0137 (8)
C20	0.0356 (12)	0.0396 (11)	0.0252 (8)	−0.0009 (9)	−0.0044 (8)	−0.0064 (8)

Geometric parameters (Å, º) top

O01—H01	0.92 (3)	C9—C8	1.540 (2)
C16—C17	1.344 (3)	C9—H9	1.0000
C16—C7	1.460 (3)	C8—H8A	0.9900
C16—H16	0.9500	C8—H8B	0.9900
N2—C1	1.407 (2)	C2—C3	1.390 (3)
N2—C9	1.467 (2)	C2—H2	0.9500
N2—H	0.98 (3)	C11—C12	1.391 (3)
N1—C7	1.297 (2)	C11—H11	0.9500
N1—C6	1.408 (2)	C4—C3	1.393 (3)
C18—C23	1.397 (3)	C4—H4	0.9500
C18—C19	1.401 (3)	C23—C22	1.389 (3)
C18—C17	1.465 (3)	C23—H23	0.9500
C17—H17	0.9500	C12—C13	1.392 (3)
C7—C8	1.505 (2)	C12—H12	0.9500
C6—C5	1.402 (3)	C15—C14	1.390 (3)
C6—C1	1.417 (2)	C15—H15	0.9500
C5—C4	1.384 (3)	C22—H22	0.9500
C5—H5	0.9500	C3—H3	0.9500
C10—C11	1.390 (3)	C19—C20	1.385 (3)
C10—C15	1.394 (3)	C19—H19	0.9500
C10—C9	1.517 (3)	C14—C13	1.387 (3)
C21—C20	1.385 (3)	C14—H14	0.9500
C21—C22	1.390 (3)	C13—H13	0.9500
C21—H21	0.9500	C20—H20	0.9500
C1—C2	1.396 (3)

C17—C16—C7	125.22 (17)	C7—C8—H8B	109.3
C17—C16—H16	117.4	C9—C8—H8B	109.3
C7—C16—H16	117.4	H8A—C8—H8B	108.0
C1—N2—C9	121.80 (14)	C3—C2—C1	122.08 (17)
C1—N2—H	108.4 (16)	C3—C2—H2	119.0
C9—N2—H	109.6 (16)	C1—C2—H2	119.0
C7—N1—C6	120.14 (16)	C10—C11—C12	121.05 (19)
C23—C18—C19	117.82 (18)	C10—C11—H11	119.5
C23—C18—C17	119.03 (17)	C12—C11—H11	119.5
C19—C18—C17	123.15 (17)	C5—C4—C3	119.37 (18)
C16—C17—C18	125.63 (17)	C5—C4—H4	120.3
C16—C17—H17	117.2	C3—C4—H4	120.3
C18—C17—H17	117.2	C22—C23—C18	121.34 (18)
N1—C7—C16	116.24 (16)	C22—C23—H23	119.3
N1—C7—C8	121.51 (17)	C18—C23—H23	119.3
C16—C7—C8	122.23 (16)	C11—C12—C13	119.81 (19)
C5—C6—N1	117.42 (15)	C11—C12—H12	120.1
C5—C6—C1	118.90 (17)	C13—C12—H12	120.1
N1—C6—C1	123.25 (17)	C14—C15—C10	119.89 (18)
C4—C5—C6	121.84 (16)	C14—C15—H15	120.1
C4—C5—H5	119.1	C10—C15—H15	120.1
C6—C5—H5	119.1	C23—C22—C21	119.86 (19)
C11—C10—C15	118.97 (18)	C23—C22—H22	120.1
C11—C10—C9	117.83 (17)	C21—C22—H22	120.1
C15—C10—C9	123.11 (17)	C2—C3—C4	119.53 (18)
C20—C21—C22	119.6 (2)	C2—C3—H3	120.2
C20—C21—H21	120.2	C4—C3—H3	120.2
C22—C21—H21	120.2	C20—C19—C18	120.93 (19)
C2—C1—N2	120.20 (16)	C20—C19—H19	119.5
C2—C1—C6	118.27 (17)	C18—C19—H19	119.5
N2—C1—C6	121.12 (17)	C13—C14—C15	121.03 (19)
N2—C9—C10	111.69 (15)	C13—C14—H14	119.5
N2—C9—C8	109.02 (14)	C15—C14—H14	119.5
C10—C9—C8	110.54 (14)	C14—C13—C12	119.2 (2)
N2—C9—H9	108.5	C14—C13—H13	120.4
C10—C9—H9	108.5	C12—C13—H13	120.4
C8—C9—H9	108.5	C19—C20—C21	120.46 (19)
C7—C8—C9	111.64 (14)	C19—C20—H20	119.8
C7—C8—H8A	109.3	C21—C20—H20	119.8
C9—C8—H8A	109.3

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O01—H01···N1	0.92 (3)	2.01 (3)	2.9300 (19)	174 (3)
C11—H11···N1ⁱ	0.95	2.51	3.426 (3)	161

Symmetry code: (i) x, y+1, z.

Acknowledgements

The authors thank Professor M. Berraho for his help and discussions in order to finalize this paper.

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