2,5-Bis(3,4-di­meth­oxy­phen­yl)-1,3,4-oxa­diazole

Moriguchi, T.; Kamoto, R.; Jalli, V.; Tsuge, A.

doi:10.1107/S241431461600167X

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 1| Part 2| February 2016| x160167

https://doi.org/10.1107/S241431461600167X

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2,5-Bis(3,4-dimethoxyphenyl)-1,3,4-oxadiazole

Tetsuji Moriguchi,^a ^* Ryota Kamoto,^a Venkataprasad Jalli ^a and Akihiko Tsuge ^a

^aDepartment of Applied Chemistry, Graduate School of Engineering, Kyushu, Institute of Technology, 1-1 Sensui-cho, Tobata-ku, Kitakyushu 804-8550, Japan
^*Correspondence e-mail: moriguch@che.kyutech.ac.jp

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 28 December 2015; accepted 27 January 2016; online 3 February 2016)

In the title compound, C₁₈H₁₈N₂O₅, which was synthesized by reacting N,N′-bis-(3,4-dimethoxybenzoyl)hydrazine with POCl₃, the dihedral angles between the central oxadiazole ring and pendant 3,4-dimethoxyphenyl rings are 11.37 (7) and 3.09 (7)°. In the crystal, weak C—H⋯O and π–π [shortest centroid–centroid separation = 3.7370 (11) Å] interactions are present, giving rise to a layered packing motif.

Keywords: crystal structure; 1,3,4-oxadiazole derivative; C—H⋯O interactions; π–π stacking.

CCDC reference: 1450256

Structure description

1,3,4-Oxadiazole and its analog derivatives are important classes of heterocyclic compounds found in many biological and pharmacological active drug molecules. It was established as privileged class of compound due to its properties in medicinal chemistry (Zou et al., 2002 ) such as anticonvulsive, antimitotic, anti-emetic, and muscle-relaxant properties. 1,3,4-Oxadiazoles are also used for platelet aggregation inhibition (Fray et al., 1995 ). Highly functionalized 1,3,4-oxadiazole derivatives are found in drug molecules such as Nesapidil, Furamizole and Raltegravir. As part of our studies in this area, we herein report the crystal structure of the title compound, C₁₈H₁₈N₂O₅ (Fig. 1).

Figure 1
The molecular conformation for the title compound, with displacement ellipsoids drawn at the 50% probability level.

In the crystal, weak C—H⋯O (Table 1; Fig. 2) and π–π [shortest centroid–centroid separation = 3.7370 (11) Å] interactions are present, giving rise to a layered packing motif

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C17—H17B⋯O5ⁱ	0.96	2.48	3.4185 (18)	165
C18—H18C⋯O4ⁱⁱ	0.96	2.52	3.4682 (18)	170
Symmetry codes: (i) $[-x, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (ii) $[x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]$ .

Figure 2
Crystal packing diagram of the title compound, viewed along the b axis, with H atoms omitted for clarity.

Synthesis and crystallization

The title compound was synthesized (Fig. 3) as follows. N,N′-bis-(3,4-dimethoxybenzoyl)-hydrazine (1 mmol) was taken in a round-bottom flask. To this 10 ml of POCl₃ was added and the mixture was refluxed 4 h, quenched with ice, allowed to warm to room temperature, and extracted twice with EtOAc. The organic layers were washed once with 50 ml water, twice with 50 ml of brine solution, dried with Na₂SO₄, and concentrated. Colourless needles of the title compound were obtained by slow evaporation of a benzene solution of crude reaction mixture (m.p. 449–451 K) at room temperature. Analysis: δ_H ¹H NMR (DMSO-d6, 500 MHz) δ 7.72 (2H, dd, J = 8.3, 2.3 Hz, H-6, H-6′), 7.61 (2H, d, J = 2.3 Hz, H-2, H-2′), 7.18 (2H, d, J = 8.3 Hz, H-5, H-5′), 3.90 (6H, s, 2 OCH₃), 3.87 (6H, s, 2 OCH₃); LCMS: MH⁺, 342.

Figure 3
Reaction scheme for the synthesis 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	C₁₈H₂₀N₂O₅
M_r	342.34
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	120
a, b, c (Å)	22.135 (4), 8.4680 (16), 8.6198 (17)
β (°)	93.287 (2)
V (Å³)	1613.0 (5)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.10
Crystal size (mm)	0.50 × 0.20 × 0.20

Data collection
Diffractometer	Bruker APEXII KY CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2009 )
T_min, T_max	0.883, 0.979
No. of measured, independent and observed [I > 2σ(I)] reflections	15058, 2852, 2525
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.031, 0.101, 1.11
No. of reflections	2852
No. of parameters	230
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.20
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008 ), SHELXL97 (Sheldrick, 2008), Mercury (Macrae et al., 2008 ).

Structural data

CCDC reference: 1450256

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S241431461600167X/hb4011sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S241431461600167X/hb4011Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S241431461600167X/hb4011Isup3.cml

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: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: APEX2 (Bruker, 2009).

2,5-Bis(3,4-dimethoxyphenyl)-1,3,4-oxadiazole top

Crystal data top

C₁₈H₂₀N₂O₅	F(000) = 720
M_r = 342.34	D_x = 1.410 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 22.135 (4) Å	Cell parameters from 6712 reflections
b = 8.4680 (16) Å	θ = 2.6–28.4°
c = 8.6198 (17) Å	µ = 0.10 mm⁻¹
β = 93.287 (2)°	T = 120 K
V = 1613.0 (5) Å³	Needle, colorless
Z = 4	0.50 × 0.20 × 0.20 mm

Data collection top

Bruker APEXII KY CCD diffractometer	2852 independent reflections
Radiation source: fine focus sealed tube	2525 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.023
ω scans	θ_max = 25.0°, θ_min = 1.8°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −26→26
T_min = 0.883, T_max = 0.979	k = −10→10
15058 measured reflections	l = −10→10

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)] = 0.031	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.101	H-atom parameters constrained
S = 1.11	w = 1/[σ²(F_o²) + (0.0579P)² + 0.3685P] where P = (F_o² + 2F_c²)/3
2852 reflections	(Δ/σ)_max < 0.001
230 parameters	Δρ_max = 0.22 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

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.

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

	x	y	z	U_iso*/U_eq
C1	0.27372 (6)	0.16288 (15)	0.21202 (14)	0.0199 (3)
C2	0.32161 (6)	0.13524 (16)	0.10688 (14)	0.0201 (3)
C3	0.33172 (6)	−0.01921 (16)	0.05734 (15)	0.0208 (3)
H3	0.308	−0.1012	0.092	0.025*
C4	0.37645 (6)	−0.05059 (15)	−0.04213 (15)	0.0206 (3)
C5	0.41349 (6)	0.07362 (16)	−0.09198 (15)	0.0214 (3)
C6	0.40284 (6)	0.22591 (16)	−0.04297 (15)	0.0232 (3)
H6	0.4267	0.3083	−0.0764	0.028*
C7	0.35692 (6)	0.25712 (16)	0.05578 (15)	0.0223 (3)
H7	0.3499	0.3601	0.0876	0.027*
C8	0.35611 (7)	−0.32582 (17)	−0.04182 (18)	0.0304 (3)
H8A	0.3632	−0.3325	0.0689	0.046*
H8B	0.3691	−0.4219	−0.0888	0.046*
H8C	0.3137	−0.3104	−0.0668	0.046*
C9	0.50117 (6)	0.14775 (18)	−0.22004 (18)	0.0311 (3)
H9A	0.4817	0.2318	−0.2786	0.047*
H9B	0.532	0.1013	−0.2795	0.047*
H9C	0.5192	0.189	−0.1245	0.047*
C10	0.21076 (6)	0.29230 (16)	0.33921 (14)	0.0208 (3)
C11	0.17893 (6)	0.42755 (16)	0.39717 (15)	0.0214 (3)
C12	0.13070 (6)	0.39841 (16)	0.49227 (14)	0.0207 (3)
H12	0.1203	0.2951	0.5158	0.025*
C13	0.09880 (6)	0.52202 (16)	0.55061 (15)	0.0207 (3)
C14	0.11468 (6)	0.67876 (16)	0.51522 (14)	0.0207 (3)
C15	0.16219 (6)	0.70723 (16)	0.42105 (15)	0.0236 (3)
H15	0.1728	0.8104	0.3973	0.028*
C16	0.19402 (6)	0.58128 (17)	0.36215 (15)	0.0233 (3)
H16	0.2258	0.6007	0.2986	0.028*
C17	0.03218 (6)	0.34858 (16)	0.67204 (16)	0.0260 (3)
H17A	0.0216	0.2969	0.5751	0.039*
H17B	−0.0024	0.3509	0.7342	0.039*
H17C	0.0645	0.2919	0.7263	0.039*
C18	0.09139 (7)	0.95081 (16)	0.53565 (17)	0.0289 (3)
H18A	0.1322	0.9784	0.5683	0.043*
H18B	0.0638	1.0192	0.5855	0.043*
H18C	0.0858	0.9623	0.425	0.043*
N1	0.24338 (5)	0.05939 (14)	0.28535 (13)	0.0241 (3)
N2	0.20193 (5)	0.14444 (14)	0.36880 (13)	0.0248 (3)
O1	0.25592 (4)	0.31369 (11)	0.24030 (10)	0.0211 (2)
O2	0.38929 (4)	−0.19607 (11)	−0.09947 (11)	0.0259 (2)
O3	0.45738 (4)	0.03030 (11)	−0.18649 (11)	0.0280 (2)
O4	0.05134 (4)	0.50644 (11)	0.64300 (10)	0.0239 (2)
O5	0.08007 (4)	0.79125 (11)	0.57747 (11)	0.0248 (2)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0205 (6)	0.0193 (7)	0.0198 (6)	0.0012 (5)	−0.0002 (5)	−0.0013 (5)
C2	0.0194 (6)	0.0228 (7)	0.0181 (6)	0.0007 (5)	0.0000 (5)	0.0007 (5)
C3	0.0199 (6)	0.0211 (7)	0.0213 (7)	−0.0023 (5)	0.0014 (5)	0.0019 (5)
C4	0.0212 (6)	0.0192 (7)	0.0213 (7)	0.0012 (5)	0.0004 (5)	−0.0004 (5)
C5	0.0197 (6)	0.0241 (7)	0.0206 (7)	0.0020 (5)	0.0028 (5)	0.0017 (5)
C6	0.0228 (7)	0.0217 (7)	0.0252 (7)	−0.0036 (5)	0.0035 (5)	0.0041 (5)
C7	0.0255 (7)	0.0185 (7)	0.0231 (7)	0.0020 (5)	0.0027 (5)	−0.0008 (5)
C8	0.0346 (8)	0.0199 (7)	0.0377 (8)	−0.0033 (6)	0.0109 (6)	−0.0030 (6)
C9	0.0230 (7)	0.0332 (8)	0.0380 (8)	−0.0024 (6)	0.0110 (6)	0.0047 (6)
C10	0.0180 (6)	0.0274 (7)	0.0172 (6)	−0.0010 (5)	0.0018 (5)	−0.0006 (5)
C11	0.0193 (6)	0.0257 (7)	0.0190 (6)	0.0010 (5)	−0.0004 (5)	−0.0011 (5)
C12	0.0211 (6)	0.0203 (7)	0.0205 (7)	−0.0014 (5)	0.0002 (5)	−0.0005 (5)
C13	0.0189 (6)	0.0251 (7)	0.0182 (6)	−0.0005 (5)	0.0006 (5)	−0.0007 (5)
C14	0.0202 (6)	0.0221 (7)	0.0198 (6)	0.0011 (5)	−0.0002 (5)	−0.0021 (5)
C15	0.0235 (7)	0.0217 (7)	0.0255 (7)	−0.0022 (5)	0.0017 (5)	0.0011 (5)
C16	0.0199 (6)	0.0289 (8)	0.0214 (7)	−0.0019 (6)	0.0034 (5)	0.0011 (5)
C17	0.0263 (7)	0.0227 (7)	0.0300 (7)	−0.0018 (6)	0.0088 (6)	0.0010 (6)
C18	0.0350 (8)	0.0194 (7)	0.0327 (8)	0.0017 (6)	0.0071 (6)	0.0012 (6)
N1	0.0238 (6)	0.0229 (6)	0.0261 (6)	0.0015 (5)	0.0069 (5)	−0.0007 (5)
N2	0.0233 (6)	0.0244 (6)	0.0275 (6)	0.0014 (5)	0.0076 (5)	−0.0018 (5)
O1	0.0214 (5)	0.0209 (5)	0.0215 (5)	0.0016 (4)	0.0052 (4)	−0.0004 (4)
O2	0.0291 (5)	0.0186 (5)	0.0310 (5)	−0.0006 (4)	0.0116 (4)	−0.0028 (4)
O3	0.0256 (5)	0.0254 (5)	0.0344 (6)	−0.0002 (4)	0.0140 (4)	0.0010 (4)
O4	0.0249 (5)	0.0213 (5)	0.0266 (5)	−0.0006 (4)	0.0099 (4)	−0.0003 (4)
O5	0.0274 (5)	0.0193 (5)	0.0283 (5)	0.0010 (4)	0.0073 (4)	−0.0013 (4)

Geometric parameters (Å, º) top

C1—N1	1.2911 (17)	C10—O1	1.3625 (15)
C1—O1	1.3625 (16)	C10—C11	1.4485 (19)
C1—C2	1.4528 (18)	C11—C16	1.382 (2)
C2—C7	1.3818 (18)	C11—C12	1.4048 (18)
C2—C3	1.3978 (19)	C12—C13	1.3740 (19)
C3—C4	1.3723 (18)	C12—H12	0.93
C3—H3	0.93	C13—O4	1.3606 (16)
C4—O2	1.3634 (16)	C13—C14	1.4108 (19)
C4—C5	1.4156 (18)	C14—O5	1.3525 (16)
C5—O3	1.3538 (16)	C14—C15	1.3861 (19)
C5—C6	1.3815 (19)	C15—C16	1.3902 (19)
C6—C7	1.3882 (19)	C15—H15	0.93
C6—H6	0.93	C16—H16	0.93
C7—H7	0.93	C17—O4	1.4289 (16)
C8—O2	1.4266 (17)	C17—H17A	0.96
C8—H8A	0.96	C17—H17B	0.96
C8—H8B	0.96	C17—H17C	0.96
C8—H8C	0.96	C18—O5	1.4243 (16)
C9—O3	1.4298 (17)	C18—H18A	0.96
C9—H9A	0.96	C18—H18B	0.96
C9—H9B	0.96	C18—H18C	0.96
C9—H9C	0.96	N1—N2	1.3978 (15)
C10—N2	1.2949 (18)

N1—C1—O1	112.63 (11)	C16—C11—C10	122.77 (12)
N1—C1—C2	127.93 (12)	C12—C11—C10	117.60 (12)
O1—C1—C2	119.44 (11)	C13—C12—C11	120.23 (12)
C7—C2—C3	119.88 (12)	C13—C12—H12	119.9
C7—C2—C1	121.65 (12)	C11—C12—H12	119.9
C3—C2—C1	118.47 (12)	O4—C13—C12	124.79 (12)
C4—C3—C2	120.39 (12)	O4—C13—C14	115.34 (11)
C4—C3—H3	119.8	C12—C13—C14	119.86 (12)
C2—C3—H3	119.8	O5—C14—C15	125.16 (12)
O2—C4—C3	125.06 (12)	O5—C14—C13	115.02 (11)
O2—C4—C5	115.15 (11)	C15—C14—C13	119.81 (12)
C3—C4—C5	119.80 (12)	C14—C15—C16	119.86 (12)
O3—C5—C6	125.30 (12)	C14—C15—H15	120.1
O3—C5—C4	115.44 (12)	C16—C15—H15	120.1
C6—C5—C4	119.26 (12)	C11—C16—C15	120.61 (12)
C5—C6—C7	120.60 (12)	C11—C16—H16	119.7
C5—C6—H6	119.7	C15—C16—H16	119.7
C7—C6—H6	119.7	O4—C17—H17A	109.5
C2—C7—C6	120.04 (12)	O4—C17—H17B	109.5
C2—C7—H7	120.0	H17A—C17—H17B	109.5
C6—C7—H7	120.0	O4—C17—H17C	109.5
O2—C8—H8A	109.5	H17A—C17—H17C	109.5
O2—C8—H8B	109.5	H17B—C17—H17C	109.5
H8A—C8—H8B	109.5	O5—C18—H18A	109.5
O2—C8—H8C	109.5	O5—C18—H18B	109.5
H8A—C8—H8C	109.5	H18A—C18—H18B	109.5
H8B—C8—H8C	109.5	O5—C18—H18C	109.5
O3—C9—H9A	109.5	H18A—C18—H18C	109.5
O3—C9—H9B	109.5	H18B—C18—H18C	109.5
H9A—C9—H9B	109.5	C1—N1—N2	106.10 (11)
O3—C9—H9C	109.5	C10—N2—N1	106.61 (10)
H9A—C9—H9C	109.5	C1—O1—C10	102.56 (10)
H9B—C9—H9C	109.5	C4—O2—C8	116.58 (10)
N2—C10—O1	112.10 (11)	C5—O3—C9	116.83 (11)
N2—C10—C11	127.93 (12)	C13—O4—C17	116.11 (10)
O1—C10—C11	119.96 (11)	C14—O5—C18	117.12 (10)
C16—C11—C12	119.63 (12)

N1—C1—C2—C7	−169.37 (13)	C12—C13—C14—O5	179.47 (11)
O1—C1—C2—C7	11.53 (19)	O4—C13—C14—C15	−179.58 (11)
N1—C1—C2—C3	10.6 (2)	C12—C13—C14—C15	0.35 (19)
O1—C1—C2—C3	−168.55 (11)	O5—C14—C15—C16	−179.14 (12)
C7—C2—C3—C4	−0.16 (19)	C13—C14—C15—C16	−0.11 (19)
C1—C2—C3—C4	179.92 (11)	C12—C11—C16—C15	0.5 (2)
C2—C3—C4—O2	−178.77 (12)	C10—C11—C16—C15	−179.81 (12)
C2—C3—C4—C5	1.49 (19)	C14—C15—C16—C11	−0.3 (2)
O2—C4—C5—O3	−1.52 (17)	O1—C1—N1—N2	0.27 (14)
C3—C4—C5—O3	178.25 (11)	C2—C1—N1—N2	−178.88 (12)
O2—C4—C5—C6	178.38 (11)	O1—C10—N2—N1	−0.03 (14)
C3—C4—C5—C6	−1.85 (19)	C11—C10—N2—N1	179.64 (12)
O3—C5—C6—C7	−179.23 (12)	C1—N1—N2—C10	−0.14 (14)
C4—C5—C6—C7	0.9 (2)	N1—C1—O1—C10	−0.28 (14)
C3—C2—C7—C6	−0.83 (19)	C2—C1—O1—C10	178.95 (11)
C1—C2—C7—C6	179.10 (12)	N2—C10—O1—C1	0.18 (14)
C5—C6—C7—C2	0.4 (2)	C11—C10—O1—C1	−179.52 (11)
N2—C10—C11—C16	177.36 (13)	C3—C4—O2—C8	−4.66 (19)
O1—C10—C11—C16	−3.00 (19)	C5—C4—O2—C8	175.09 (12)
N2—C10—C11—C12	−2.9 (2)	C6—C5—O3—C9	9.25 (19)
O1—C10—C11—C12	176.74 (11)	C4—C5—O3—C9	−170.85 (12)
C16—C11—C12—C13	−0.21 (19)	C12—C13—O4—C17	−3.73 (18)
C10—C11—C12—C13	−179.96 (11)	C14—C13—O4—C17	176.20 (11)
C11—C12—C13—O4	179.74 (11)	C15—C14—O5—C18	3.64 (19)
C11—C12—C13—C14	−0.19 (19)	C13—C14—O5—C18	−175.43 (11)
O4—C13—C14—O5	−0.46 (17)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C17—H17B···O5ⁱ	0.96	2.48	3.4185 (18)	165
C18—H18C···O4ⁱⁱ	0.96	2.52	3.4682 (18)	170

Symmetry codes: (i) −x, y−1/2, −z+3/2; (ii) x, −y+3/2, z−1/2.

Acknowledgements

We are grateful to the Center for Instrumental Analysis, Kyushu Institute of Technology (KITCIA), for the X-ray analysis.

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