organic compounds
(E)-1,1′-(Diazene-1,2-diyl)bis(cyclohexane-1-carbonitrile)
aSchool of Chemistry, University of Dublin, Trinity College, Dublin 2, Ireland
*Correspondence e-mail: bakerrj@tcd.ie
The whole molecule of the title compound, C14H20N4, is generated by inversion symmetry. The mid-point of the N=N bond is situated on the inversion centre. The conformation about this central N=N bond is E. The carbonitrile groups occupy axial positions on the cyclohexane rings. In the crystal, there are no significant intermolecular interactions present.
Keywords: crystal structure; VAZO-88; radical initiator; diazene; carbonitrile; cyclohexane.
CCDC reference: 1536557
Structure description
The title compound, known as VAZO-88, is a well known radical initiator that has also been used as a ligand in coordination chemistry (Chainok et al., 2010).
The whole molecule of the title compound, illustrated in Fig. 1, is generated by inversion symmetry. The mid-point of the N=N bond is situated on the inversion centre. The conformation about the central N1=N1′ bond, of 1.231 (2) Å, is E. The carbonitrile groups occupy axial positions on the cyclohexane rings and the C2—C3≡N4 bond angle is 176.58 (18) °, with bond length C3≡N4 being 1.147 (2) Å.
In the crystal, molecules stack along the a-axis direction (Fig. 2), but there are no significant intermolecular interactions present.
Synthesis and crystallization
During an attempted radical
reaction, using commercially available VAZO-88, we obtained a few colourless crystals of the title compound, on slow evaporation of a hexane solution.Refinement
Crystal data, data collection and structure .
details are summarized in Table 1Structural data
CCDC reference: 1536557
https://doi.org/10.1107/S2414314617003698/su4139sup1.cif
contains datablocks Global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617003698/su4139Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314617003698/su4139Isup3.mol
Supporting information file. DOI: https://doi.org/10.1107/S2414314617003698/su4139Isup4.cml
Data collection: APEX3 (Bruker, 2015); cell
SAINT (Bruker, 2015); data reduction: SAINT (Bruker, 2015); program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).C14H20N4 | F(000) = 264 |
Mr = 244.34 | Dx = 1.170 Mg m−3 |
Monoclinic, P21/n | Cu Kα radiation, λ = 1.54184 Å |
a = 5.8740 (19) Å | Cell parameters from 4485 reflections |
b = 21.077 (7) Å | θ = 4.2–69.5° |
c = 5.974 (2) Å | µ = 0.57 mm−1 |
β = 110.372 (13)° | T = 100 K |
V = 693.4 (4) Å3 | Block, colourless |
Z = 2 | 0.16 × 0.13 × 0.12 mm |
Bruker APEXII CCD diffractometer | 1299 independent reflections |
Radiation source: microfocus sealed X-ray tube, Incoatec Iµs | 1213 reflections with I > 2σ(I) |
Mirror optics monochromator | Rint = 0.033 |
Detector resolution: 7.9 pixels mm-1 | θmax = 69.7°, θmin = 8.2° |
ω and φ scans | h = −7→7 |
Absorption correction: multi-scan (SADABS; Bruker, 2015) | k = −25→25 |
Tmin = 0.666, Tmax = 0.753 | l = −7→7 |
7548 measured reflections |
Refinement on F2 | Primary atom site location: dual |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.059 | H-atom parameters constrained |
wR(F2) = 0.160 | w = 1/[σ2(Fo2) + (0.0875P)2 + 0.4078P] where P = (Fo2 + 2Fc2)/3 |
S = 1.06 | (Δ/σ)max < 0.001 |
1299 reflections | Δρmax = 0.47 e Å−3 |
82 parameters | Δρmin = −0.16 e Å−3 |
0 restraints |
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. |
x | y | z | Uiso*/Ueq | ||
C2 | 0.5458 (3) | 0.42030 (8) | 0.4069 (3) | 0.0259 (4) | |
C3 | 0.7721 (3) | 0.40938 (8) | 0.6143 (3) | 0.0286 (4) | |
C5 | 0.3418 (3) | 0.37594 (8) | 0.4188 (3) | 0.0295 (4) | |
H5A | 0.3201 | 0.3814 | 0.5748 | 0.035* | |
H5B | 0.1876 | 0.3878 | 0.2920 | 0.035* | |
C6 | 0.3981 (3) | 0.30654 (8) | 0.3880 (3) | 0.0309 (5) | |
H6A | 0.5404 | 0.2930 | 0.5261 | 0.037* | |
H6B | 0.2580 | 0.2800 | 0.3846 | 0.037* | |
C7 | 0.4513 (3) | 0.29635 (8) | 0.1585 (3) | 0.0320 (5) | |
H7A | 0.3027 | 0.3049 | 0.0194 | 0.038* | |
H7B | 0.4982 | 0.2516 | 0.1493 | 0.038* | |
C8 | 0.6554 (3) | 0.33973 (8) | 0.1480 (3) | 0.0306 (5) | |
H8A | 0.8083 | 0.3281 | 0.2772 | 0.037* | |
H8B | 0.6797 | 0.3337 | −0.0065 | 0.037* | |
C9 | 0.5977 (3) | 0.40919 (8) | 0.1749 (3) | 0.0280 (4) | |
H9A | 0.4544 | 0.4221 | 0.0368 | 0.034* | |
H9B | 0.7368 | 0.4358 | 0.1757 | 0.034* | |
N1 | 0.4544 (3) | 0.48574 (7) | 0.4049 (3) | 0.0285 (4) | |
N4 | 0.9502 (3) | 0.39882 (8) | 0.7674 (3) | 0.0382 (5) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C2 | 0.0226 (8) | 0.0294 (9) | 0.0254 (8) | 0.0012 (6) | 0.0079 (7) | −0.0005 (6) |
C3 | 0.0255 (9) | 0.0331 (9) | 0.0291 (9) | 0.0010 (7) | 0.0118 (8) | −0.0008 (7) |
C5 | 0.0215 (8) | 0.0357 (10) | 0.0333 (9) | −0.0010 (7) | 0.0120 (7) | −0.0009 (7) |
C6 | 0.0252 (9) | 0.0316 (10) | 0.0364 (10) | −0.0015 (7) | 0.0114 (7) | 0.0020 (7) |
C7 | 0.0306 (9) | 0.0295 (9) | 0.0341 (9) | −0.0002 (7) | 0.0089 (7) | −0.0023 (7) |
C8 | 0.0307 (9) | 0.0336 (10) | 0.0298 (9) | 0.0015 (7) | 0.0133 (7) | −0.0010 (7) |
C9 | 0.0247 (9) | 0.0347 (10) | 0.0255 (9) | −0.0012 (6) | 0.0099 (7) | −0.0005 (7) |
N1 | 0.0247 (8) | 0.0320 (8) | 0.0301 (7) | −0.0008 (5) | 0.0111 (6) | −0.0023 (5) |
N4 | 0.0284 (9) | 0.0505 (10) | 0.0323 (8) | 0.0056 (7) | 0.0063 (7) | 0.0012 (7) |
C2—C3 | 1.486 (2) | C6—C7 | 1.524 (3) |
C2—C5 | 1.541 (2) | C7—H7A | 0.9900 |
C2—C9 | 1.537 (2) | C7—H7B | 0.9900 |
C2—N1 | 1.479 (2) | C7—C8 | 1.526 (2) |
C3—N4 | 1.147 (2) | C8—H8A | 0.9900 |
C5—H5A | 0.9900 | C8—H8B | 0.9900 |
C5—H5B | 0.9900 | C8—C9 | 1.524 (2) |
C5—C6 | 1.525 (2) | C9—H9A | 0.9900 |
C6—H6A | 0.9900 | C9—H9B | 0.9900 |
C6—H6B | 0.9900 | N1—N1i | 1.231 (3) |
C3—C2—C5 | 110.60 (14) | C6—C7—H7A | 109.4 |
C3—C2—C9 | 109.11 (14) | C6—C7—H7B | 109.4 |
C9—C2—C5 | 110.54 (14) | C6—C7—C8 | 111.24 (14) |
N1—C2—C3 | 111.60 (13) | H7A—C7—H7B | 108.0 |
N1—C2—C5 | 106.26 (13) | C8—C7—H7A | 109.4 |
N1—C2—C9 | 108.69 (13) | C8—C7—H7B | 109.4 |
N4—C3—C2 | 176.58 (18) | C7—C8—H8A | 109.3 |
C2—C5—H5A | 109.3 | C7—C8—H8B | 109.3 |
C2—C5—H5B | 109.3 | H8A—C8—H8B | 108.0 |
H5A—C5—H5B | 107.9 | C9—C8—C7 | 111.40 (14) |
C6—C5—C2 | 111.80 (14) | C9—C8—H8A | 109.3 |
C6—C5—H5A | 109.3 | C9—C8—H8B | 109.3 |
C6—C5—H5B | 109.3 | C2—C9—H9A | 109.4 |
C5—C6—H6A | 109.3 | C2—C9—H9B | 109.4 |
C5—C6—H6B | 109.3 | C8—C9—C2 | 111.26 (14) |
H6A—C6—H6B | 108.0 | C8—C9—H9A | 109.4 |
C7—C6—C5 | 111.41 (14) | C8—C9—H9B | 109.4 |
C7—C6—H6A | 109.3 | H9A—C9—H9B | 108.0 |
C7—C6—H6B | 109.3 | N1i—N1—C2 | 114.07 (18) |
C2—C5—C6—C7 | −54.82 (19) | C6—C7—C8—C9 | −56.00 (19) |
C3—C2—C5—C6 | −66.44 (18) | C7—C8—C9—C2 | 56.17 (19) |
C3—C2—C9—C8 | 66.81 (18) | C9—C2—C5—C6 | 54.51 (19) |
C3—C2—N1—N1i | −15.1 (2) | C9—C2—N1—N1i | −135.45 (18) |
C5—C2—C9—C8 | −55.02 (19) | N1—C2—C5—C6 | 172.27 (13) |
C5—C2—N1—N1i | 105.57 (19) | N1—C2—C9—C8 | −171.28 (13) |
C5—C6—C7—C8 | 55.17 (19) |
Symmetry code: (i) −x+1, −y+1, −z+1. |
Funding information
Funding for this research was provided by: Higher Education Commission, Pakistanhttps://doi.org/10.13039/501100004681.
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