1-(2-Cyano­eth­yl)-1H-imidazole-4,5-dicarbonitrile

In the title tricyano­nitrile compound, C₈H₅N₅, the N-substituted cyano­ethyl group is offset to the imidazole ring [dihedral angle = 75.41 (15)°].

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.047
• wR factor = 0.124
• Data-to-parameter ratio = 19.2

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT906_ALERT_3_C Large K value in the Analysis of Variance ......      2.243
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1
PLAT913_ALERT_3_C Missing # of Very Strong Reflections in FCF ....          1

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details in CIF ....          ?
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K
PLAT371_ALERT_2_G Long   C(sp2)-C(sp1) Bond  C3     -   C8     ...       1.42 Ang.
PLAT371_ALERT_2_G Long   C(sp2)-C(sp1) Bond  C6     -   C7     ...       1.42 Ang.
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600        297

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   3 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   6 ALERT level G = General information/check it is not something unexpected

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

Imidazole ligands have been used with remarkable success in coordination chemistry over past decades (Li et al., 1955). Some of the reasons are for this are that the N atom plays an important role in the formation of metal complexes (Fujita et al., 1994), and that imidazole complexes show conjugate acid-base properties and good complexation coordination performance in the solid state. Some examples of imidazole complexes have been reported (Martin & Edsall, 1958). Here we report on a new imidazole compound, the polycyano-substituted imidazole, the title compound C₈H₅N₅.

In the molecular structure of this compound (Fig. 1). The bond lengths and bond angles are within normal ranges. The N-bound cyanoethyl side chain is offset to the imidazole ring [torsion angles C5—N4—C4—C2 and N4—C4—C2—C1, -78.0 (2) and -61.4 (2)° respectively]. The dihedral angle between the cyanoethyl group defined by atoms N1—C1—C2—C4 and the imidazole ring is 75.41 (15)°]

Related literature

For background to the application of imidazole compounds as ligands, see: Li et al. (1955). For the significance of N atoms in metal complex chemistry, see: Fujita et al. (1994). For examples of some imidazole complexes, see: Martin & Edsall (1958).

S2. Experimental

A mixture of 4,5-dicyanoimidazole (1.18 g, 10 mmol) and powdered potassium hydroxide (100 mg) (as a catalyst) in acrylonitrile (20 ml) was heated at 130 °C for 3 hr in a sealed tube, after which the solution was evaporated to dryness. The crude product obtained was recrystallized twice from acetone to give a pure blue product. Yield: 89.7%. Anal: Calcd. for C₈H₅N₅: C, 56.1; H, 2.9; N, 40.9%: Found: C, 56.15; H, 2.96; N, 40.89%.

S3. Refinement

All H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms [C—H = 0.93 Å (aromatic) and 0.97 Å (methylene)], with U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: CrystalRED (Rigaku/MSC, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures

Figure 1. The structure of the title compound, showing 30% probability displacement ellipsoids and the atom-numbering scheme.

1-(2-Cyanoethyl)-1H-imidazole-4,5-dicarbonitrile

Crystal data

C8H5N5	Z = 2
Mr = 171.17	F(000) = 176
Triclinic, P1	Dx = 1.326 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.4831 (6) Å	Cell parameters from 1220 reflections
b = 6.7538 (6) Å	θ = 3.2–29.0°
c = 10.4040 (11) Å	µ = 0.09 mm^−1
α = 77.865 (9)°	T = 293 K
β = 84.297 (8)°	Block, blue
γ = 74.499 (8)°	0.43 × 0.25 × 0.16 mm
V = 428.71 (7) Å^3

Data collection

Rigaku R-AXIS RAPID CCD diffractometer	2265 independent reflections
Radiation source: SuperNova (Mo) X-ray Source	1439 reflections with I > 2σ(I)
Mirror monochromator	Rint = 0.020
Detector resolution: 16.1623 pixels mm^-1	θmax = 29.0°, θmin = 3.2°
ω scans	h = −8→8
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	k = −9→9
Tmin = 0.973, Tmax = 0.986	l = −13→14
3805 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.124	H-atom parameters constrained
S = 1.09	w = 1/[σ^2(Fo^2) + (0.0428P)^2 + 0.0566P] where P = (Fo^2 + 2Fc^2)/3
2265 reflections	(Δ/σ)max < 0.001
118 parameters	Δρmax = 0.13 e Å^−3
0 restraints	Δρmin = −0.21 e Å^−3

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
N4	0.25841 (19)	0.19385 (19)	0.19288 (12)	0.0356 (3)
N5	0.5564 (2)	0.2497 (2)	0.08299 (14)	0.0438 (4)
C8	0.5883 (2)	0.0426 (2)	0.13842 (15)	0.0367 (4)
C7	0.3704 (3)	−0.1861 (3)	0.28068 (17)	0.0462 (4)
C6	0.4074 (2)	0.0040 (2)	0.20743 (15)	0.0353 (4)
C5	0.3567 (2)	0.3342 (2)	0.11807 (16)	0.0420 (4)
H5A	0.2902	0.4759	0.0938	0.050*
N3	0.9384 (2)	−0.2328 (3)	0.10572 (16)	0.0632 (5)
C4	0.0347 (2)	0.2341 (3)	0.24210 (16)	0.0425 (4)
H4A	−0.0060	0.1025	0.2662	0.051*
H4B	−0.0557	0.3222	0.1723	0.051*
C3	0.7842 (3)	−0.1089 (3)	0.12134 (16)	0.0430 (4)
C2	−0.0044 (3)	0.3398 (3)	0.36024 (17)	0.0502 (5)
H2A	0.0338	0.4727	0.3357	0.060*
H2B	−0.1557	0.3685	0.3862	0.060*
N2	0.3452 (3)	−0.3409 (3)	0.3388 (2)	0.0740 (6)
C1	0.1183 (3)	0.2129 (3)	0.47147 (19)	0.0534 (5)
N1	0.2152 (3)	0.1117 (3)	0.55746 (19)	0.0798 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N4	0.0358 (7)	0.0354 (7)	0.0338 (7)	−0.0091 (5)	0.0008 (5)	−0.0038 (5)
N5	0.0430 (7)	0.0361 (7)	0.0470 (8)	−0.0091 (6)	0.0055 (6)	−0.0008 (6)
C8	0.0379 (8)	0.0356 (8)	0.0347 (8)	−0.0078 (6)	−0.0010 (6)	−0.0049 (7)
C7	0.0486 (10)	0.0386 (9)	0.0500 (10)	−0.0131 (8)	−0.0032 (8)	−0.0023 (8)
C6	0.0409 (8)	0.0323 (8)	0.0324 (8)	−0.0096 (6)	−0.0032 (6)	−0.0040 (6)
C5	0.0433 (9)	0.0322 (8)	0.0452 (9)	−0.0077 (7)	0.0030 (7)	−0.0004 (7)
N3	0.0538 (9)	0.0568 (10)	0.0660 (11)	0.0044 (8)	0.0037 (8)	−0.0100 (8)
C4	0.0348 (8)	0.0482 (9)	0.0436 (10)	−0.0118 (7)	0.0015 (7)	−0.0067 (8)
C3	0.0430 (9)	0.0419 (9)	0.0407 (9)	−0.0082 (7)	0.0011 (7)	−0.0053 (7)
C2	0.0505 (10)	0.0462 (10)	0.0514 (11)	−0.0108 (8)	0.0123 (8)	−0.0124 (8)
N2	0.0836 (13)	0.0471 (10)	0.0879 (14)	−0.0269 (9)	−0.0008 (10)	0.0065 (9)
C1	0.0591 (12)	0.0660 (13)	0.0442 (11)	−0.0288 (10)	0.0112 (9)	−0.0204 (10)
N1	0.0850 (14)	0.1093 (17)	0.0516 (11)	−0.0391 (12)	−0.0047 (10)	−0.0104 (11)

Geometric parameters (Å, º)

N4—C5	1.3509 (19)	C5—H5A	0.9300
N4—C6	1.3729 (18)	N3—C3	1.142 (2)
N4—C4	1.4630 (19)	C4—C2	1.515 (2)
N5—C5	1.3172 (19)	C4—H4A	0.9700
N5—C8	1.3641 (19)	C4—H4B	0.9700
C8—C6	1.370 (2)	C2—C1	1.452 (3)
C8—C3	1.424 (2)	C2—H2A	0.9700
C7—N2	1.137 (2)	C2—H2B	0.9700
C7—C6	1.416 (2)	C1—N1	1.135 (2)
C5—N4—C6	106.18 (12)	N4—C4—C2	112.63 (13)
C5—N4—C4	126.80 (13)	N4—C4—H4A	109.1
C6—N4—C4	126.95 (13)	C2—C4—H4A	109.1
C5—N5—C8	104.35 (13)	N4—C4—H4B	109.1
N5—C8—C6	110.83 (13)	C2—C4—H4B	109.1
N5—C8—C3	122.98 (14)	H4A—C4—H4B	107.8
C6—C8—C3	126.16 (14)	N3—C3—C8	178.15 (19)
N2—C7—C6	178.5 (2)	C1—C2—C4	112.42 (15)
C8—C6—N4	105.61 (13)	C1—C2—H2A	109.1
C8—C6—C7	129.79 (15)	C4—C2—H2A	109.1
N4—C6—C7	124.59 (14)	C1—C2—H2B	109.1
N5—C5—N4	113.02 (14)	C4—C2—H2B	109.1
N5—C5—H5A	123.5	H2A—C2—H2B	107.9
N4—C5—H5A	123.5	N1—C1—C2	179.1 (2)
C5—N4—C4—C2	−78.0 (2)	C8—N5—C5—N4	0.08 (17)
C6—N4—C4—C2	105.74 (18)	C5—N5—C8—C3	178.04 (15)
C4—N4—C5—N5	−176.61 (14)	C5—N5—C8—C6	−0.40 (17)
C6—N4—C5—N5	0.25 (18)	C1—C2—C4—N4	−61.4 (2)
C4—N4—C6—C7	−3.8 (2)	N4—C6—C8—N5	0.55 (17)
C4—N4—C6—C8	176.38 (14)	N4—C6—C8—C3	−177.82 (15)
C5—N4—C6—C7	179.31 (15)	C7—C6—C8—N5	−179.22 (16)
C5—N4—C6—C8	−0.48 (16)	C7—C6—C8—C3	2.4 (3)