4-(2-Oxoprop­yl)-1,3-bis­(prop-2-yn-1-yl)-2,3,4,5-tetra­hydro-1,5-benzodiazepin-2(1H)-one

Sebhaoui, J.; El Bakri, Y.; Rayni, I.; Essassi, E.M.; Mague, J.T.

doi:10.1107/S2414314616010130

organic compounds

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ISSN: 2414-3146

Volume 1| Part 6| June 2016| x161013

doi:10.1107/S2414314616010130

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4-(2-Oxopropyl)-1,3-bis(prop-2-yn-1-yl)-2,3,4,5-tetrahydro-1,5-benzodiazepin-2(1H)-one

Jihad Sebhaoui,^a ^* Youness El Bakri,^a Ibtissam Rayni,^a El Mokhtar Essassi ^a and Joel T. Mague ^b

^aLaboratoire de Chimie Organique Hétérocyclique, URAC 21, Pôle de Compétence Pharmacochimie, Av Ibn Battouta, BP 1014, Faculté des Sciences, Mohammed V University, Rabat, Morocco, and ^bDepartment of Chemistry, Tulane University, New Orleans, LA 70118, USA
^*Correspondence e-mail: sebhaoui.jihad@gmail.com

Edited by J. Simpson, University of Otago, New Zealand (Received 16 June 2016; accepted 21 June 2016; online 24 June 2016)

In the title molecule, C₁₈H₁₆N₂O₂, the seven-membered diazepinone ring adopts a boat conformation. An intramolecular N—H⋯O hydrogen bond encloses an S(6) ring. The two propynyl substituents each point away from the same face of the benzodiazepinone ring system. In the crystal, C—H⋯O hydrogen bonds form double chains of molecules along the c-axis direction.

Keywords: crystal structure; benzodiazepine; alkyne; hydrogen bonds.

CCDC reference: 1486935

Structure description

Benzodiazepine derivatives have been the object of intense investigation in medicinal chemistry because of their remarkable ability to depress activity in the central nervous system and are now one of the most widely prescribed class of psychotropic drugs (Zellou et al., 1998 , 1999 ; Rudolph et al., 1999 ). The area of biological interest of 1,5-benzodiazepine derivatives has been extended to include antibiotics (Knabe et al., 1995 ) and the treatment of various diseases such as cancer (Atwal et al., 1987 ), viral infection (HIV) (Di Braccio et al., 2001 ) and cardiovascular disorders (Claremon et al., 1998

The conformation of the title molecule is partially determined by an intramolecular N2—H2A⋯O2 hydrogen bond (Table 1 and Fig. 1). The heterocyclic ring adopts a boat conformation with puckering parameters Q(2) = 0.899 (1) Å, φ(2) = 206.26 (8)°, Q(3) = 0.261 (1) Å and φ(3) = 303.1 (3)°. The two propynyl substituents, C14—C15—H15 and C17—C18—H18 each point away from the same face of the benzodiazepinone ring system and one of these is involved in C18—H18⋯O2ⁱ hydrogen bonds that form C(10) chains along c. Additional weaker C12—H12A⋯O1ⁱⁱ contacts form inversion dimers, enclosing R₂²(16) rings, and these link adjacent chains to produce a double chain propagating along c, Fig. 2.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2A⋯O2	0.939 (18)	1.918 (18)	2.6678 (13)	135.2 (14)
C18—H18⋯O2ⁱ	0.95	2.35	3.3012 (16)	178
C12—H12A⋯O1ⁱⁱ	0.98	2.70	3.664 (2)	168
Symmetry codes: (i) x, y, z-1; (ii) -x, -y, -z+1.

Figure 1
The title molecule with labeling scheme and 50% probability ellipsoids. The intramolecular hydrogen bond is shown as a dotted line.

Figure 2
Packing viewed along the a axis.

Synthesis and crystallization

To a solution of (4E)-2-oxopropylidene-1,5-benzodiazepin-2-one (0.01 mol, 2.16 g) in N,N-dimethylformamid (60 ml), was added K₂CO₃ (0.02 mol, 2.76 g), propargyl bromide (0.02 mol, 5,84 g) and tetra n-butylammonium bromide (0.001 mol, 0.321 g). The reaction mixture was stirred at room temperature for 48 h. The solution was filtered and the solvent was removed under reduced pressure. The residue was chromatographed on a silica-gel column using hexane and ethyl acetate (80/20) as eluents. Recrystallization from this solution gave the title compound as a white crystals suitable for X-ray investigation.

Refinement

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

Table 2
Experimental details

Crystal data
Chemical formula	C₁₈H₁₆N₂O₂
M_r	292.33
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	150
a, b, c (Å)	8.6905 (2), 9.0249 (3), 10.8240 (3)
α, β, γ (°)	68.803 (1), 78.520 (1), 72.980 (1)
V (Å³)	752.69 (4)
Z	2
Radiation type	Cu Kα
μ (mm⁻¹)	0.69
Crystal size (mm)	0.17 × 0.13 × 0.13

Data collection
Diffractometer	Bruker D8 VENTURE PHOTON 100 CMOS
Absorption correction	Multi-scan (SADABS; Bruker, 2016 )
T_min, T_max	0.82, 0.92
No. of measured, independent and observed [I > 2σ(I)] reflections	5877, 2802, 2554
R_int	0.026
(sin θ/λ)_max (Å⁻¹)	0.618

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.038, 0.107, 1.05
No. of reflections	2802
No. of parameters	205
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.20, −0.22
Computer programs: APEX3 and SAINT (Bruker, 2016), SHELXT (Sheldrick, 2015a ), SHELXL2014 (Sheldrick, 2015b ), DIAMOND (Brandenburg & Putz, 2012 ), Mercury (Macrae et al., 2008 ) and SHELXTL (Sheldrick, 2008 ).

Structural data

CCDC reference: 1486935

Crystal structure: contains datablocks global, I. DOI: 10.1107/S2414314616010130/sj4049sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2414314616010130/sj4049Isup2.hkl

Supporting information file. DOI: 10.1107/S2414314616010130/sj4049Isup4.cdx

Supporting information file. DOI: 10.1107/S2414314616010130/sj4049Isup4.cml

checkCIF report

Computing details top

Data collection: APEX3 (Bruker, 2016); cell refinement: SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg & Putz, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

4-(2-Oxopropylidene)-1,3-bis(prop-2-yn-1-yl)-2,3,4,5-tetrahydro-1H-1,5-benzodiazepin-2-one top

Crystal data top

C₁₈H₁₆N₂O₂	Z = 2
M_r = 292.33	F(000) = 308
Triclinic, P1	D_x = 1.290 Mg m⁻³
a = 8.6905 (2) Å	Cu Kα radiation, λ = 1.54178 Å
b = 9.0249 (3) Å	Cell parameters from 5019 reflections
c = 10.8240 (3) Å	θ = 5.4–72.4°
α = 68.803 (1)°	µ = 0.69 mm⁻¹
β = 78.520 (1)°	T = 150 K
γ = 72.980 (1)°	Block, colourless
V = 752.69 (4) Å³	0.17 × 0.13 × 0.13 mm

Data collection top

Bruker D8 VENTURE PHOTON 100 CMOS diffractometer	2802 independent reflections
Radiation source: INCOATEC IµS micro–focus source	2554 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.026
Detector resolution: 10.4167 pixels mm^-1	θ_max = 72.4°, θ_min = 5.4°
ω scans	h = −10→10
Absorption correction: multi-scan (SADABS, Bruker, 2016)	k = −11→11
T_min = 0.82, T_max = 0.92	l = −12→13
5877 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.038	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.107	w = 1/[σ²(F_o²) + (0.0623P)² + 0.166P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max < 0.001
2802 reflections	Δρ_max = 0.20 e Å⁻³
205 parameters	Δρ_min = −0.22 e Å⁻³
0 restraints	Extinction correction: SHELXL2014 (Sheldrick, 2015b), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0185 (19)

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. 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 > 2sigma(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. H-atoms attached to carbon were placed in calculated positions (C—H = 0.95 - 0.99 Å) and included as riding contributions with isotropic displacement parameters 1.2 - 1.5 times those of the attached atoms.

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

	x	y	z	U_iso*/U_eq
O1	0.29131 (10)	−0.00462 (10)	0.35510 (9)	0.0299 (2)
O2	0.08148 (11)	0.34999 (11)	0.72733 (8)	0.0283 (2)
H2A	0.225 (2)	0.395 (2)	0.5665 (18)	0.041 (4)*
N1	0.44188 (11)	0.17555 (12)	0.32357 (10)	0.0235 (2)
N2	0.24209 (12)	0.37133 (12)	0.48668 (10)	0.0222 (2)
C1	0.36309 (13)	0.42678 (14)	0.38710 (12)	0.0220 (3)
C2	0.39430 (14)	0.57554 (15)	0.37361 (13)	0.0265 (3)
H2	0.3329	0.6365	0.4301	0.032*
C3	0.51333 (16)	0.63519 (16)	0.27926 (14)	0.0313 (3)
H3	0.5339	0.7361	0.2716	0.038*
C4	0.60277 (16)	0.54749 (17)	0.19572 (14)	0.0345 (3)
H4	0.6834	0.5892	0.1298	0.041*
C5	0.57435 (15)	0.39900 (17)	0.20856 (14)	0.0305 (3)
H5	0.6356	0.3396	0.1509	0.037*
C6	0.45668 (14)	0.33579 (14)	0.30532 (12)	0.0232 (3)
C7	0.29822 (14)	0.13457 (14)	0.33893 (11)	0.0221 (3)
C8	0.14850 (13)	0.27376 (14)	0.34124 (12)	0.0210 (3)
H8	0.1702	0.3757	0.2708	0.025*
C9	0.13465 (13)	0.29586 (13)	0.47525 (12)	0.0205 (3)
C10	0.02525 (13)	0.23893 (14)	0.57948 (12)	0.0224 (3)
H10	−0.0429	0.1812	0.5672	0.027*
C11	0.00868 (14)	0.26233 (14)	0.70643 (12)	0.0235 (3)
C12	−0.10022 (16)	0.17527 (17)	0.81733 (13)	0.0311 (3)
H12A	−0.1656	0.1320	0.7809	0.047*
H12B	−0.1717	0.2522	0.8611	0.047*
H12C	−0.0345	0.0848	0.8824	0.047*
C13	0.59039 (15)	0.04794 (15)	0.31350 (14)	0.0289 (3)
H13A	0.6825	0.0767	0.3329	0.035*
H13B	0.5781	−0.0576	0.3814	0.035*
C14	0.62650 (15)	0.02832 (15)	0.18111 (14)	0.0305 (3)
C15	0.65303 (19)	0.00942 (19)	0.07573 (16)	0.0421 (4)
H15	0.6744	−0.0058	−0.0090	0.050*
C16	−0.00053 (14)	0.24122 (15)	0.31059 (12)	0.0249 (3)
H16A	−0.0093	0.1284	0.3643	0.030*
H16B	−0.0994	0.3185	0.3341	0.030*
C17	0.01388 (14)	0.26199 (15)	0.16813 (13)	0.0271 (3)
C18	0.03206 (17)	0.28788 (17)	0.05105 (14)	0.0336 (3)
H18	0.0466	0.3086	−0.0425	0.040*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0299 (5)	0.0217 (4)	0.0404 (5)	−0.0055 (3)	−0.0037 (4)	−0.0135 (4)
O2	0.0341 (5)	0.0294 (5)	0.0250 (5)	−0.0108 (4)	−0.0018 (4)	−0.0113 (4)
N1	0.0198 (5)	0.0203 (5)	0.0298 (5)	−0.0021 (4)	−0.0012 (4)	−0.0104 (4)
N2	0.0231 (5)	0.0224 (5)	0.0234 (5)	−0.0063 (4)	−0.0021 (4)	−0.0095 (4)
C1	0.0194 (5)	0.0221 (6)	0.0241 (6)	−0.0043 (4)	−0.0048 (4)	−0.0062 (5)
C2	0.0255 (6)	0.0227 (6)	0.0329 (7)	−0.0040 (5)	−0.0076 (5)	−0.0100 (5)
C3	0.0299 (6)	0.0262 (6)	0.0407 (7)	−0.0117 (5)	−0.0080 (5)	−0.0080 (6)
C4	0.0281 (6)	0.0361 (7)	0.0388 (7)	−0.0152 (5)	0.0008 (5)	−0.0079 (6)
C5	0.0241 (6)	0.0327 (7)	0.0350 (7)	−0.0081 (5)	0.0022 (5)	−0.0131 (6)
C6	0.0201 (5)	0.0215 (6)	0.0280 (6)	−0.0042 (4)	−0.0044 (4)	−0.0079 (5)
C7	0.0236 (6)	0.0217 (6)	0.0216 (6)	−0.0042 (4)	−0.0017 (4)	−0.0091 (5)
C8	0.0199 (5)	0.0207 (6)	0.0231 (6)	−0.0039 (4)	−0.0027 (4)	−0.0085 (5)
C9	0.0194 (5)	0.0166 (5)	0.0250 (6)	−0.0001 (4)	−0.0053 (4)	−0.0080 (5)
C10	0.0218 (5)	0.0209 (5)	0.0251 (6)	−0.0047 (4)	−0.0029 (4)	−0.0082 (5)
C11	0.0229 (5)	0.0207 (6)	0.0246 (6)	−0.0019 (4)	−0.0048 (4)	−0.0062 (5)
C12	0.0325 (7)	0.0364 (7)	0.0243 (6)	−0.0128 (5)	−0.0015 (5)	−0.0067 (6)
C13	0.0220 (6)	0.0245 (6)	0.0373 (7)	0.0006 (5)	−0.0034 (5)	−0.0114 (5)
C14	0.0236 (6)	0.0235 (6)	0.0408 (8)	−0.0042 (5)	0.0050 (5)	−0.0118 (6)
C15	0.0430 (8)	0.0423 (8)	0.0427 (9)	−0.0178 (7)	0.0148 (6)	−0.0200 (7)
C16	0.0224 (6)	0.0278 (6)	0.0270 (6)	−0.0053 (5)	−0.0038 (4)	−0.0119 (5)
C17	0.0246 (6)	0.0283 (6)	0.0319 (7)	−0.0050 (5)	−0.0058 (5)	−0.0134 (5)
C18	0.0370 (7)	0.0386 (7)	0.0302 (7)	−0.0101 (6)	−0.0055 (5)	−0.0151 (6)

Geometric parameters (Å, º) top

O1—C7	1.2219 (14)	C8—C16	1.5290 (15)
O2—C11	1.2478 (15)	C8—H8	1.0000
N1—C7	1.3662 (15)	C9—C10	1.3713 (17)
N1—C6	1.4280 (15)	C10—C11	1.4376 (16)
N1—C13	1.4726 (15)	C10—H10	0.9500
N2—C9	1.3529 (14)	C11—C12	1.5017 (17)
N2—C1	1.4088 (15)	C12—H12A	0.9800
N2—H2A	0.939 (18)	C12—H12B	0.9800
C1—C2	1.3975 (16)	C12—H12C	0.9800
C1—C6	1.4027 (17)	C13—C14	1.4681 (18)
C2—C3	1.3823 (18)	C13—H13A	0.9900
C2—H2	0.9500	C13—H13B	0.9900
C3—C4	1.388 (2)	C14—C15	1.182 (2)
C3—H3	0.9500	C15—H15	0.9500
C4—C5	1.3862 (19)	C16—C17	1.4685 (17)
C4—H4	0.9500	C16—H16A	0.9900
C5—C6	1.3969 (17)	C16—H16B	0.9900
C5—H5	0.9500	C17—C18	1.1888 (19)
C7—C8	1.5247 (15)	C18—H18	0.9500
C8—C9	1.5113 (15)

C7—N1—C6	124.46 (9)	C16—C8—H8	108.0
C7—N1—C13	116.81 (10)	N2—C9—C10	122.14 (10)
C6—N1—C13	118.50 (9)	N2—C9—C8	115.06 (10)
C9—N2—C1	125.92 (10)	C10—C9—C8	122.76 (10)
C9—N2—H2A	114.6 (11)	C9—C10—C11	123.22 (10)
C1—N2—H2A	119.3 (11)	C9—C10—H10	118.4
C2—C1—C6	119.19 (11)	C11—C10—H10	118.4
C2—C1—N2	118.15 (10)	O2—C11—C10	122.72 (11)
C6—C1—N2	122.61 (10)	O2—C11—C12	119.61 (11)
C3—C2—C1	120.91 (11)	C10—C11—C12	117.67 (10)
C3—C2—H2	119.5	C11—C12—H12A	109.5
C1—C2—H2	119.5	C11—C12—H12B	109.5
C2—C3—C4	119.91 (12)	H12A—C12—H12B	109.5
C2—C3—H3	120.0	C11—C12—H12C	109.5
C4—C3—H3	120.0	H12A—C12—H12C	109.5
C5—C4—C3	119.92 (12)	H12B—C12—H12C	109.5
C5—C4—H4	120.0	C14—C13—N1	112.32 (10)
C3—C4—H4	120.0	C14—C13—H13A	109.1
C4—C5—C6	120.72 (12)	N1—C13—H13A	109.1
C4—C5—H5	119.6	C14—C13—H13B	109.1
C6—C5—H5	119.6	N1—C13—H13B	109.1
C5—C6—C1	119.31 (11)	H13A—C13—H13B	107.9
C5—C6—N1	118.84 (11)	C15—C14—C13	178.17 (14)
C1—C6—N1	121.74 (10)	C14—C15—H15	180.0
O1—C7—N1	122.21 (11)	C17—C16—C8	109.32 (10)
O1—C7—C8	123.08 (10)	C17—C16—H16A	109.8
N1—C7—C8	114.65 (10)	C8—C16—H16A	109.8
C9—C8—C7	105.29 (9)	C17—C16—H16B	109.8
C9—C8—C16	115.45 (9)	C8—C16—H16B	109.8
C7—C8—C16	111.90 (9)	H16A—C16—H16B	108.3
C9—C8—H8	108.0	C18—C17—C16	174.84 (13)
C7—C8—H8	108.0	C17—C18—H18	180.0

C9—N2—C1—C2	141.12 (11)	C13—N1—C7—C8	−176.84 (10)
C9—N2—C1—C6	−41.41 (16)	O1—C7—C8—C9	103.58 (12)
C6—C1—C2—C3	1.36 (17)	N1—C7—C8—C9	−73.45 (12)
N2—C1—C2—C3	178.93 (11)	O1—C7—C8—C16	−22.58 (16)
C1—C2—C3—C4	0.50 (19)	N1—C7—C8—C16	160.39 (10)
C2—C3—C4—C5	−1.1 (2)	C1—N2—C9—C10	176.94 (10)
C3—C4—C5—C6	−0.2 (2)	C1—N2—C9—C8	−0.93 (15)
C4—C5—C6—C1	2.10 (19)	C7—C8—C9—N2	74.96 (11)
C4—C5—C6—N1	−174.11 (11)	C16—C8—C9—N2	−161.10 (10)
C2—C1—C6—C5	−2.63 (17)	C7—C8—C9—C10	−102.89 (12)
N2—C1—C6—C5	179.92 (11)	C16—C8—C9—C10	21.05 (15)
C2—C1—C6—N1	173.46 (10)	N2—C9—C10—C11	3.68 (17)
N2—C1—C6—N1	−3.99 (17)	C8—C9—C10—C11	−178.62 (10)
C7—N1—C6—C5	−136.02 (12)	C9—C10—C11—O2	7.22 (18)
C13—N1—C6—C5	38.24 (16)	C9—C10—C11—C12	−172.22 (11)
C7—N1—C6—C1	47.87 (16)	C7—N1—C13—C14	77.54 (14)
C13—N1—C6—C1	−137.87 (12)	C6—N1—C13—C14	−97.15 (13)
C6—N1—C7—O1	−179.55 (11)	C9—C8—C16—C17	166.39 (10)
C13—N1—C7—O1	6.11 (17)	C7—C8—C16—C17	−73.20 (12)
C6—N1—C7—C8	−2.49 (16)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···O2	0.939 (18)	1.918 (18)	2.6678 (13)	135.2 (14)
C18—H18···O2ⁱ	0.95	2.35	3.3012 (16)	178
C12—H12A···O1ⁱⁱ	0.98	2.70	3.664 (2)	168

Symmetry codes: (i) x, y, z−1; (ii) −x, −y, −z+1.

Acknowledgements

The support of NSF–MRI Grant No. 1228232 for the purchase of the diffractometer and Tulane University for support of the Tulane Crystallography Laboratory are gratefully acknowledged.

References

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