2,5-Di-p-tolyl-1,3,4-oxa­diazo­le

The mol­ecule of the title compound, C₁₆H₁₄N₂O, consists of two equivalent parts related by a twofold axis of the space group. The O atom occupies a special position on this twofold axis.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.053
• wR factor = 0.156
• Data-to-parameter ratio = 13.0

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



PLAT_031  Alert C Refined Extinction Parameter within Range ......       2.50 Sigma


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 1 Alert Level C = Please check

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Computing details

Data collection: CAD-4 Operations Manual (Enraf-Nonius, 1977); cell refinement: CAD-4 Operations Manual; data reduction: PROCESS_in MolEN (Fair, 1990); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL-NT (Sheldrick, 1999); software used to prepare material for publication: SHELXL97.

2,5-Di-p-tolyl-1,3,4-oxadiazole

Crystal data

C16H14N2O	F(000) = 528
Mr = 250.29	Dx = 1.277 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71069 Å
a = 11.404 (2) Å	Cell parameters from 25 reflections
b = 11.751 (2) Å	θ = 12–20°
c = 10.870 (1) Å	µ = 0.08 mm^−1
β = 116.62 (2)°	T = 293 K
V = 1302.3 (3) Å^3	Needle, colourless
Z = 4	0.45 × 0.12 × 0.11 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	Rint = 0.030
Radiation source: fine-focus sealed tube	θmax = 25.1°, θmin = 2.6°
Graphite monochromator	h = −13→12
2θ–ω scans	k = 0→14
1207 measured reflections	l = −10→12
1155 independent reflections	3 standard reflections every 120 min
606 reflections with I > 2σ(I)	intensity decay: 0.8%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.053	H-atom parameters constrained
wR(F^2) = 0.156	w = 1/[σ^2(Fo^2) + (0.1082P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.91	(Δ/σ)max < 0.001
1155 reflections	Δρmax = 0.27 e Å^−3
89 parameters	Δρmin = −0.19 e Å^−3
23 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.005 (2)

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.0000	−0.00372 (17)	0.2500	0.0600 (6)
N3	0.04729 (18)	0.17335 (17)	0.31948 (18)	0.0669 (6)
C2	0.0712 (2)	0.06886 (19)	0.3552 (2)	0.0560 (6)
C6	0.15820 (18)	0.01850 (18)	0.4872 (2)	0.0538 (6)
C7	0.2450 (2)	0.08726 (19)	0.5929 (2)	0.0624 (6)
H7	0.2469	0.1652	0.5793	0.081*
C8	0.3282 (2)	0.0399 (2)	0.7179 (2)	0.0669 (7)
H8	0.3862	0.0866	0.7878	0.087*
C9	0.3274 (2)	−0.0756 (2)	0.7415 (2)	0.0626 (7)
C10	0.2400 (2)	−0.1417 (2)	0.6365 (3)	0.0729 (7)
H10	0.2374	−0.2196	0.6504	0.081 (8)*
C11	0.1559 (2)	−0.0959 (2)	0.5107 (3)	0.0703 (7)
H11	0.0974	−0.1429	0.4416	0.091*
C12	0.4204 (2)	−0.1279 (3)	0.8760 (2)	0.0845 (9)
H121	0.4742	−0.0695	0.9369	0.110*
H122	0.4752	−0.1823	0.8604	0.110*
H123	0.3715	−0.1654	0.9166	0.110*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0650 (12)	0.0550 (13)	0.0596 (12)	0.000	0.0275 (10)	0.000
N3	0.0822 (14)	0.0590 (13)	0.0583 (11)	−0.0002 (9)	0.0304 (10)	−0.0006 (9)
C2	0.0584 (11)	0.0596 (14)	0.0575 (12)	−0.0044 (10)	0.0327 (10)	−0.0060 (10)
C6	0.0533 (12)	0.0585 (13)	0.0557 (12)	−0.0015 (9)	0.0299 (10)	−0.0026 (10)
C7	0.0742 (13)	0.0562 (14)	0.0611 (13)	0.0003 (10)	0.0343 (11)	0.0026 (10)
C8	0.0764 (14)	0.0685 (15)	0.0595 (14)	−0.0045 (12)	0.0338 (11)	−0.0052 (11)
C9	0.0612 (13)	0.0747 (16)	0.0640 (14)	0.0071 (10)	0.0389 (12)	0.0085 (11)
C10	0.0825 (15)	0.0557 (14)	0.0859 (17)	−0.0019 (12)	0.0424 (14)	0.0103 (13)
C11	0.0739 (14)	0.0624 (15)	0.0718 (15)	−0.0065 (11)	0.0302 (12)	0.0023 (12)
C12	0.0837 (17)	0.103 (2)	0.0730 (17)	0.0117 (16)	0.0401 (14)	0.0208 (15)

Geometric parameters (Å, º)

O1—C2	1.365 (2)	C8—H8	0.9300
O1—C2^i	1.365 (2)	C9—C10	1.372 (3)
N3—C2	1.280 (3)	C9—C12	1.500 (3)
N3—N3^i	1.409 (4)	C10—C11	1.380 (3)
C2—C6	1.455 (3)	C10—H10	0.9300
C6—C11	1.371 (3)	C11—H11	0.9300
C6—C7	1.390 (3)	C12—H121	0.9600
C7—C8	1.379 (3)	C12—H122	0.9600
C7—H7	0.9300	C12—H123	0.9600
C8—C9	1.382 (3)
C2—O1—C2^i	102.6 (2)	C10—C9—C12	120.8 (2)
C2—N3—N3^i	106.39 (12)	C8—C9—C12	121.5 (2)
N3—C2—O1	112.29 (19)	C9—C10—C11	121.8 (2)
N3—C2—C6	130.4 (2)	C9—C10—H10	119.1
O1—C2—C6	117.3 (2)	C11—C10—H10	119.1
C11—C6—C7	118.8 (2)	C6—C11—C10	120.3 (2)
C11—C6—C2	121.4 (2)	C6—C11—H11	119.9
C7—C6—C2	119.8 (2)	C10—C11—H11	119.9
C8—C7—C6	120.0 (2)	C9—C12—H121	109.5
C8—C7—H7	120.0	C9—C12—H122	109.5
C6—C7—H7	120.0	H121—C12—H122	109.5
C7—C8—C9	121.4 (2)	C9—C12—H123	109.5
C7—C8—H8	119.3	H121—C12—H123	109.5
C9—C8—H8	119.3	H122—C12—H123	109.5
C10—C9—C8	117.7 (2)

Symmetry code: (i) −x, y, −z+1/2.