Bis(imidazol-1-yl)methane

In the title compound, C₇H₈N₄, the C atom of the bridging methyl­ene group lies on a twofold rotation axis. The dihedral angle between the symmetry-related imidazole rings is 75.0 (2)°. The crystal packing is stabilized by van der Waals forces.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.048
• wR factor = 0.123
• Data-to-parameter ratio = 9.8

checkCIF/PLATON results

No syntax errors found



Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.757     0.998
            Tmin(prime) and Tmax expected:      0.956     0.972
            RR(prime) =      0.771
            Please check that your absorption correction is appropriate.
PLAT031_ALERT_4_C Refined Extinction Parameter within Range ......       2.75 Sigma
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.77
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.97
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT199_ALERT_1_C Check the Reported _cell_measurement_temperature        293 K
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.17 Ratio

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.00
           From the CIF: _reflns_number_total                508
           Count of symmetry unique reflns          508
           Completeness (_total/calc)            100.00%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   7 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

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

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Computing details

Data collection: SMART (Bruker, 1998); cell refinement: SMART; data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1998); software used to prepare material for publication: SHELXTL.

Bis(imidazol-1-yl)methane

Crystal data

C7H8N4	Dx = 1.332 Mg m^−3
Mr = 148.17	Melting point = 429–431 K
Orthorhombic, P21212	Mo Kα radiation, λ = 0.71073 Å
a = 8.0357 (18) Å	Cell parameters from 1241 reflections
b = 10.545 (2) Å	θ = 6.4–53.0°
c = 4.3613 (10) Å	µ = 0.09 mm^−1
V = 369.55 (15) Å^3	T = 293 K
Z = 2	Block, colourless
F(000) = 156	0.49 × 0.45 × 0.32 mm

Data collection

Bruker SMART CCD area-detector diffractometer	508 independent reflections
Radiation source: fine-focus sealed tube	461 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.079
φ and ω scans	θmax = 27.0°, θmin = 3.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→7
Tmin = 0.757, Tmax = 0.998	k = −13→13
2176 measured reflections	l = −5→5

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)] = 0.048	H-atom parameters constrained
wR(F^2) = 0.123	w = 1/[σ^2(Fo^2) + (0.0898P)^2 + 0.003P] where P = (Fo^2 + 2Fc^2)/3
S = 1.02	(Δ/σ)max = 0.007
508 reflections	Δρmax = 0.19 e Å^−3
52 parameters	Δρmin = −0.17 e Å^−3
0 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: 0.11 (4)

Special details

Experimental. ¹H NMR (300 MHz, CDCl₃): δ 6.87 (2H, s), 6.77 (2H, s), 5.77 (2H, s); ¹³C NMR: δ 144.8, 128.9, 119.1, 55.7. It was crystallized by slow evaporation of a chloroform–methanol (5:1 v/v) mixture (yield 200 mg, 78%; m.p. 441–442 K)

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
N1	0.2438 (2)	0.27007 (13)	0.3079 (5)	0.0676 (7)
N2	0.11821 (17)	0.43083 (13)	0.0844 (4)	0.0432 (5)
C1	0.1230 (2)	0.30409 (17)	0.1293 (6)	0.0581 (6)
H1A	0.0480	0.2476	0.0418	0.070*
C2	0.3227 (3)	0.38050 (16)	0.3841 (6)	0.0586 (6)
H2A	0.4151	0.3859	0.5118	0.070*
C3	0.2487 (2)	0.48015 (14)	0.2497 (4)	0.0535 (6)
H3A	0.2794	0.5650	0.2652	0.064*
C4	0.0000	0.5000	−0.1006 (7)	0.0512 (7)
H4A	0.0594	0.5590	−0.2315	0.061*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0609 (10)	0.0453 (10)	0.0966 (15)	0.0108 (8)	0.0019 (10)	0.0085 (9)
N2	0.0378 (7)	0.0373 (8)	0.0544 (8)	0.0037 (6)	0.0042 (6)	−0.0022 (7)
C1	0.0563 (11)	0.0360 (9)	0.0820 (13)	−0.0020 (8)	0.0003 (12)	−0.0038 (9)
C2	0.0429 (9)	0.0606 (11)	0.0723 (12)	0.0085 (8)	−0.0020 (10)	0.0009 (11)
C3	0.0416 (9)	0.0442 (10)	0.0747 (11)	−0.0034 (7)	−0.0026 (10)	−0.0022 (9)
C4	0.0489 (13)	0.0548 (14)	0.0500 (12)	0.0096 (11)	0.000	0.000

Geometric parameters (Å, º)

N1—C1	1.295 (3)	C2—C3	1.342 (2)
N1—C2	1.367 (2)	C2—H2A	0.9300
N2—C1	1.351 (2)	C3—H3A	0.9300
N2—C3	1.375 (2)	C4—N2^i	1.444 (2)
N2—C4	1.444 (2)	C4—H4A	0.9700
C1—H1A	0.9300	C4—H4A^i	0.9700
C1—N1—C2	104.94 (16)	C3—C2—H2A	124.6
C1—N2—C3	106.04 (16)	N1—C2—H2A	124.6
C1—N2—C4	126.83 (14)	C2—C3—N2	105.71 (14)
C3—N2—C4	127.13 (13)	C2—C3—H3A	127.1
N1—C1—N2	112.50 (18)	N2—C3—H3A	127.1
N1—C1—H1A	123.8	N2^i—C4—N2	112.1 (2)
N2—C1—H1A	123.8	N2^i—C4—H4A	109.2
C3—C2—N1	110.81 (19)	N2—C4—H4A	109.2
C2—N1—C1—N2	−0.1 (2)	C1—N2—C3—C2	−0.3 (2)
C3—N2—C1—N1	0.3 (2)	C4—N2—C3—C2	179.8 (2)
C4—N2—C1—N1	−179.90 (19)	C1—N2—C4—N2^i	106.63 (19)
C1—N1—C2—C3	−0.1 (2)	C3—N2—C4—N2^i	−73.57 (15)
N1—C2—C3—N2	0.3 (2)

Symmetry code: (i) −x, −y+1, z.