Redetermination of bis­(benzimidazol-2-yl­methyl)­amine

The title compound, C₁₆H₁₅N₅, has been redetermined from data collected at 150 K. It crystallizes in space group Pbca, with four mol­ecules in the unit cell, and the mol­ecule is disordered about a centre of symmetry.

Key indicators

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.034
• wR factor = 0.084
• Data-to-parameter ratio = 10.9

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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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: SHELXTL (Sheldrick, 2000); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Bis(benzimidazol-2-ylmethyl)amine

Crystal data

C16H15N5	Dx = 1.365 Mg m^−3
Mr = 277.33	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pbca	Cell parameters from 3898 reflections
a = 8.2512 (8) Å	θ = 2.4–23.6°
b = 9.5494 (9) Å	µ = 0.09 mm^−1
c = 17.1248 (17) Å	T = 150 K
V = 1349.3 (2) Å^3	Lozenge, colourless
Z = 4	0.39 × 0.10 × 0.10 mm
F(000) = 584

Data collection

Bruker SMART CCD area-detector diffractometer	1188 independent reflections
Radiation source: fine-focus sealed tube	1041 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.023
φ and ω scans	θmax = 25.0°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 2000)	h = −9→9
Tmin = 0.990, Tmax = 0.991	k = −11→11
8858 measured reflections	l = −19→20

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)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.084	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0345P)^2 + 0.574P] where P = (Fo^2 + 2Fc^2)/3
1188 reflections	(Δ/σ)max < 0.001
109 parameters	Δρmax = 0.16 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	Occ. (<1)
N1	0.14296 (13)	0.14050 (11)	0.06345 (6)	0.0267 (3)
C1	0.04002 (15)	0.07379 (13)	0.11606 (7)	0.0253 (3)
C2	−0.08579 (16)	0.12661 (14)	0.16164 (8)	0.0332 (3)
H2	−0.1163	0.2224	0.1586	0.040*
C3	−0.16482 (18)	0.03550 (16)	0.21137 (9)	0.0401 (4)
H3	−0.2512	0.0694	0.2428	0.048*
C4	−0.12033 (18)	−0.10581 (16)	0.21639 (9)	0.0378 (4)
H4	−0.1760	−0.1652	0.2519	0.045*
C5	0.00233 (16)	−0.16086 (14)	0.17099 (8)	0.0310 (3)
H5	0.0315	−0.2570	0.1738	0.037*
C6	0.08103 (15)	−0.06872 (13)	0.12103 (7)	0.0246 (3)
N2	0.20959 (13)	−0.08624 (11)	0.07027 (6)	0.0260 (3)
C7	0.24061 (17)	0.04101 (13)	0.03827 (7)	0.0275 (3)
C8	0.3494 (6)	0.0587 (7)	−0.0292 (3)	0.0329 (11)	0.50
H8A	0.2824	0.0733	−0.0765	0.050*	0.50
H8B	0.4146	0.1445	−0.0212	0.050*	0.50
C8'	0.4003 (6)	0.0684 (7)	−0.0073 (3)	0.0354 (11)	0.50
H8'1	0.4091	0.0006	−0.0508	0.050*	0.50
H8'2	0.3973	0.1638	−0.0299	0.050*	0.50
N3	0.4572 (3)	−0.0554 (3)	−0.04334 (14)	0.0357 (6)	0.50
H2N	0.2674	−0.1684	0.0642	0.050*
H3N	0.4089	−0.1366	−0.0484	0.050*	0.50

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0280 (6)	0.0213 (6)	0.0309 (6)	−0.0006 (5)	0.0001 (5)	0.0006 (5)
C1	0.0225 (7)	0.0227 (6)	0.0306 (7)	−0.0021 (5)	−0.0034 (5)	0.0006 (5)
C2	0.0298 (7)	0.0260 (7)	0.0439 (8)	0.0030 (6)	0.0039 (6)	−0.0003 (6)
C3	0.0319 (8)	0.0372 (8)	0.0510 (9)	0.0017 (7)	0.0135 (7)	−0.0005 (7)
C4	0.0330 (8)	0.0336 (8)	0.0469 (9)	−0.0069 (6)	0.0094 (7)	0.0059 (7)
C5	0.0294 (7)	0.0226 (6)	0.0411 (8)	−0.0038 (6)	−0.0015 (6)	0.0029 (6)
C6	0.0210 (6)	0.0232 (6)	0.0298 (7)	−0.0009 (5)	−0.0025 (5)	−0.0004 (5)
N2	0.0257 (6)	0.0205 (5)	0.0316 (6)	0.0017 (4)	0.0003 (5)	0.0010 (5)
C7	0.0304 (7)	0.0231 (6)	0.0289 (7)	−0.0009 (5)	0.0006 (6)	0.0016 (5)
C8	0.030 (3)	0.0323 (18)	0.037 (3)	−0.006 (2)	0.0033 (17)	0.000 (2)
C8'	0.036 (3)	0.032 (2)	0.038 (3)	0.002 (2)	0.0107 (19)	0.002 (2)
N3	0.0275 (12)	0.0363 (13)	0.0433 (14)	−0.0046 (10)	0.0042 (11)	−0.0097 (11)

Geometric parameters (Å, º)

N1—C7	1.3183 (17)	N2—C7	1.3573 (17)
N1—C1	1.3925 (16)	N2—H2N	0.924
C1—C2	1.3932 (19)	C7—C8	1.473 (7)
C1—C6	1.4048 (18)	C7—C8'	1.553 (6)
C2—C3	1.381 (2)	C8—N3	1.427 (7)
C2—H2	0.950	C8—H8A	0.990
C3—C4	1.401 (2)	C8—H8B	0.990
C3—H3	0.950	C8'—N3^i	1.466 (5)
C4—C5	1.380 (2)	C8'—H8'1	0.990
C4—H4	0.950	C8'—H8'2	0.990
C5—C6	1.3885 (18)	N3—C8'^i	1.466 (5)
C5—H5	0.950	N3—H3N	0.876
C6—N2	1.3816 (16)
C7—N1—C1	104.76 (11)	C6—N2—H2N	124.7
N1—C1—C2	130.64 (12)	N1—C7—N2	113.44 (11)
N1—C1—C6	109.60 (11)	N1—C7—C8	123.1 (3)
C2—C1—C6	119.75 (12)	N2—C7—C8	122.3 (3)
C3—C2—C1	117.98 (13)	N1—C7—C8'	124.1 (3)
C3—C2—H2	121.0	N2—C7—C8'	120.9 (3)
C1—C2—H2	121.0	N3—C8—C7	115.2 (5)
C2—C3—C4	121.39 (14)	N3—C8—H8A	108.5
C2—C3—H3	119.3	C7—C8—H8A	108.5
C4—C3—H3	119.3	N3—C8—H8B	108.5
C5—C4—C3	121.63 (13)	C7—C8—H8B	108.5
C5—C4—H4	119.2	H8A—C8—H8B	107.5
C3—C4—H4	119.2	N3^i—C8'—C7	111.7 (4)
C4—C5—C6	116.66 (12)	N3^i—C8'—H8'1	109.3
C4—C5—H5	121.7	C7—C8'—H8'1	109.3
C6—C5—H5	121.7	N3^i—C8'—H8'2	109.3
N2—C6—C5	132.07 (12)	C7—C8'—H8'2	109.3
N2—C6—C1	105.32 (11)	H8'1—C8'—H8'2	107.9
C5—C6—C1	122.58 (12)	C8—N3—C8'^i	117.7 (4)
C7—N2—C6	106.88 (10)	C8—N3—H3N	114.2
C7—N2—H2N	128.1	C8'^i—N3—H3N	110.3
C7—N1—C1—C2	178.83 (14)	C1—C6—N2—C7	0.32 (13)
C7—N1—C1—C6	0.13 (14)	C1—N1—C7—N2	0.08 (15)
N1—C1—C2—C3	−177.75 (13)	C1—N1—C7—C8	168.1 (2)
C6—C1—C2—C3	0.8 (2)	C1—N1—C7—C8'	−165.9 (2)
C1—C2—C3—C4	0.2 (2)	C6—N2—C7—N1	−0.26 (15)
C2—C3—C4—C5	−1.1 (2)	C6—N2—C7—C8	−168.4 (2)
C3—C4—C5—C6	1.0 (2)	C6—N2—C7—C8'	166.3 (2)
C4—C5—C6—N2	177.67 (13)	N1—C7—C8—N3	174.3 (2)
C4—C5—C6—C1	0.1 (2)	N2—C7—C8—N3	−18.7 (4)
N1—C1—C6—N2	−0.28 (14)	N1—C7—C8'—N3^i	101.3 (4)
C2—C1—C6—N2	−179.15 (11)	N2—C7—C8'—N3^i	−63.7 (5)
N1—C1—C6—C5	177.86 (12)	C8—C7—C8'—N3^i	−164.0 (16)
C2—C1—C6—C5	−1.0 (2)	C7—C8—N3—C8'^i	−76.8 (5)
C5—C6—N2—C7	−177.57 (14)

Symmetry code: (i) −x+1, −y, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2N···N1^ii	0.92	1.97	2.8816 (15)	169

Symmetry code: (ii) −x+1/2, y−1/2, z.