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Acta Cryst. (2009). E65, o1014    [ doi:10.1107/S1600536809012781 ]

1,3-Bis(1-benzyl-1H-benzimidazol-2-yl)-2-oxapropane

H. Wu, R. Yun, K. Wang, X. Huang and Q. Sun

Abstract top

In the title compound, C30H26N4O, the dihedral angle between the two benzimidazole rings is 69.35 (9)°. The dihedral angles between the benzimidazole ring system and the phenyl ring are 76.79 (12) and 86.10 (11)° in the two benzylbenzimidazole moieties.

Comment top

Benzimidazole derivatives, such as mebendazole and albendazole, are used as anthelmintic drugs. More recently, the antiprotozoal activity of 2- and 5-substituted benzimidazoles has been reported (Navarrete-Vázquez et al. 2001). The benzimidazole core is of interest because of its diverse biological activities, and it is a well known structure in medicinal chemistry (Horton et al. 2003). The molecular structure of the title compound is shown in Fig. 1. The dihedral angle between N3/N4/C10-C16 and C18-C23 is 76.79 (12)° and that between N1/N2/C1-C7 and C25-C30 is 86.10 (11)°.

Related literature top

For the biological activity of the benzimidazole core, see: Horton et al. (2003). For the antiprotozoal activity of 2- and 5-substituted benzimidazoles, see: Navarrete-Vázquez et al. (2001).

Experimental top

A solution of 5.56 (20 mmol) of 1,3-bis(benzimidazol-2-yl)-2-oxopropane with 1.56 g (40 mmol) potassium in 150 ml tetrahydrofuran followed by addition of 5.06 g (40 mmol) benzyl bromide was concentrated and recrystallized from methanol, formimg white block crystals suitable for X-ray diffraction studies. (found: C, 78.51; H, 5.73; N,12.24 Calcd. for C30H26N4O: C, 78.58; H, 5.71; N, 12.22)

Refinement top

All H atoms were positioned geometrically with C—H distances ranging from 0.95 to 0.99 Å and allowed to ride on their parent atoms with Uiso(H) = 1.2 Ueq of the carrier atom.

Computing details top

Data collection: RAPID-AUTO (Rigaku/MSC, 2004); cell refinement: RAPID-AUTO (Rigaku/MSC, 2004); data reduction: RAPID-AUTO (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: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound. Hydrogen atoms have been omitted for clarity and the displacement ellipsoids are shown at the 30% probability level.
1,3-Bis(1-benzyl-1H-benzimidazol-2-yl)-2-oxapropane top
Crystal data top
C30H26N4OZ = 2
Mr = 458.55F(000) = 484
Triclinic, P1Dx = 1.301 Mg m−3
Hall symbol: -P 1Melting point = 450–451 K
a = 8.5477 (3) ÅMo Kα radiation, λ = 0.71073 Å
b = 11.8976 (5) ÅCell parameters from 5275 reflections
c = 12.3961 (5) Åθ = 3.0–27.5°
α = 101.300 (1)°µ = 0.08 mm−1
β = 92.394 (1)°T = 153 K
γ = 107.765 (1)°Block, white
V = 1170.28 (8) Å30.58 × 0.52 × 0.19 mm
Data collection top
Rigaku R-AXIS Spider
diffractometer		5275 independent reflections
Radiation source: fine-focus sealed tube4542 reflections with I > 2σ(I)
graphiteRint = 0.013
φ and ω scansθmax = 27.5°, θmin = 3.0°
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		h = −11→10
Tmin = 0.955, Tmax = 0.985k = −15→15
11531 measured reflectionsl = −16→16
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.038H-atom parameters constrained
wR(F2) = 0.126 w = 1/[σ2(Fo2) + (0.0736P)2 + 0.3041P]
where P = (Fo2 + 2Fc2)/3
S = 1.09(Δ/σ)max < 0.001
5275 reflectionsΔρmax = 0.50 e Å−3
317 parametersΔρmin = −0.34 e Å−3
0 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.044 (4)
Crystal data top
C30H26N4Oγ = 107.765 (1)°
Mr = 458.55V = 1170.28 (8) Å3
Triclinic, P1Z = 2
a = 8.5477 (3) ÅMo Kα radiation
b = 11.8976 (5) ŵ = 0.08 mm−1
c = 12.3961 (5) ÅT = 153 K
α = 101.300 (1)°0.58 × 0.52 × 0.19 mm
β = 92.394 (1)°
Data collection top
Rigaku R-AXIS Spider
diffractometer		4542 reflections with I > 2σ(I)
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		Rint = 0.013
Tmin = 0.955, Tmax = 0.985θmax = 27.5°
11531 measured reflectionsStandard reflections: 0
5275 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.038H-atom parameters constrained
wR(F2) = 0.126Δρmax = 0.50 e Å−3
S = 1.09Δρmin = −0.34 e Å−3
5275 reflectionsAbsolute structure: ?
317 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

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 (Å2) top
xyzUiso*/Ueq
O0.80479 (11)0.49510 (8)0.70677 (7)0.0252 (2)
N10.73219 (13)0.71312 (9)0.90708 (8)0.0233 (2)
N20.54296 (12)0.52783 (9)0.85764 (8)0.0214 (2)
N30.99857 (12)0.31236 (9)0.79071 (8)0.0231 (2)
N40.77779 (12)0.22141 (9)0.66368 (8)0.0231 (2)
C10.58038 (15)0.71864 (10)0.93941 (9)0.0213 (2)
C20.53783 (16)0.81685 (11)0.99680 (10)0.0256 (3)
H20.61720.89531.01820.031*
C30.37662 (17)0.79594 (12)1.02133 (10)0.0276 (3)
H30.34510.86101.06110.033*
C40.25816 (16)0.68035 (12)0.98864 (10)0.0276 (3)
H40.14830.66951.00650.033*
C50.29667 (15)0.58181 (11)0.93114 (10)0.0247 (3)
H50.21640.50390.90860.030*
C60.46015 (15)0.60377 (10)0.90831 (9)0.0208 (2)
C70.70389 (15)0.59876 (11)0.85997 (9)0.0217 (2)
C80.83822 (16)0.55036 (12)0.82143 (10)0.0264 (3)
H8A0.94460.61710.83490.032*
H8B0.84810.49020.86400.032*
C90.92732 (15)0.44005 (11)0.67180 (10)0.0258 (3)
H9A1.03850.49750.70130.031*
H9B0.92080.42270.59000.031*
C100.90483 (14)0.32529 (11)0.71040 (10)0.0222 (2)
C110.79369 (14)0.13374 (11)0.71787 (9)0.0221 (2)
C120.70094 (16)0.01242 (12)0.70590 (11)0.0284 (3)
H120.6078−0.02570.65200.034*
C130.75138 (17)−0.04945 (12)0.77646 (11)0.0295 (3)
H130.6919−0.13250.77060.035*
C140.88820 (17)0.00726 (12)0.85663 (11)0.0283 (3)
H140.9187−0.03820.90400.034*
C150.98002 (15)0.12805 (12)0.86844 (10)0.0258 (3)
H151.07220.16610.92310.031*
C160.93194 (14)0.19187 (10)0.79690 (10)0.0212 (2)
C170.64947 (15)0.20654 (12)0.57568 (10)0.0257 (3)
H17A0.61590.28030.58730.031*
H17B0.55160.13780.58080.031*
C180.70267 (15)0.18411 (11)0.46087 (10)0.0236 (3)
C190.66731 (18)0.24654 (12)0.38477 (11)0.0312 (3)
H190.61150.30400.40570.037*
C200.7125 (2)0.22588 (14)0.27833 (12)0.0403 (4)
H200.68690.26860.22660.048*
C210.7950 (2)0.14290 (14)0.24755 (12)0.0393 (3)
H210.82750.12940.17500.047*
C220.82983 (19)0.07973 (13)0.32288 (12)0.0363 (3)
H220.88610.02250.30200.044*
C230.78271 (17)0.09980 (12)0.42866 (11)0.0303 (3)
H230.80550.05530.47970.036*
C240.46863 (16)0.39871 (10)0.81196 (10)0.0250 (3)
H24A0.39010.36350.86220.030*
H24B0.55650.36030.80950.030*
C250.37816 (14)0.36798 (10)0.69711 (10)0.0214 (2)
C260.28424 (15)0.24803 (12)0.65272 (12)0.0289 (3)
H260.27730.18850.69500.035*
C270.20114 (18)0.21494 (13)0.54754 (13)0.0383 (3)
H270.13830.13270.51790.046*
C280.20876 (18)0.30063 (14)0.48511 (12)0.0382 (3)
H280.15050.27780.41320.046*
C290.30168 (19)0.41940 (14)0.52837 (12)0.0352 (3)
H290.30790.47870.48590.042*
C300.38665 (17)0.45315 (12)0.63410 (11)0.0287 (3)
H300.45080.53520.66310.034*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O0.0294 (4)0.0282 (4)0.0204 (4)0.0137 (4)0.0023 (3)0.0041 (3)
N10.0256 (5)0.0211 (5)0.0220 (5)0.0072 (4)−0.0003 (4)0.0032 (4)
N20.0266 (5)0.0177 (5)0.0187 (5)0.0064 (4)−0.0011 (4)0.0031 (4)
N30.0228 (5)0.0223 (5)0.0224 (5)0.0066 (4)0.0023 (4)0.0019 (4)
N40.0236 (5)0.0234 (5)0.0208 (5)0.0060 (4)−0.0005 (4)0.0043 (4)
C10.0254 (6)0.0206 (5)0.0176 (5)0.0066 (4)0.0005 (4)0.0051 (4)
C20.0331 (6)0.0207 (6)0.0217 (6)0.0085 (5)0.0023 (5)0.0023 (4)
C30.0374 (7)0.0288 (6)0.0200 (6)0.0159 (5)0.0062 (5)0.0044 (5)
C40.0297 (6)0.0346 (7)0.0204 (6)0.0120 (5)0.0047 (5)0.0075 (5)
C50.0265 (6)0.0262 (6)0.0192 (5)0.0046 (5)0.0011 (4)0.0060 (4)
C60.0268 (6)0.0208 (5)0.0147 (5)0.0072 (4)0.0002 (4)0.0045 (4)
C70.0250 (6)0.0221 (6)0.0181 (5)0.0079 (4)−0.0011 (4)0.0046 (4)
C80.0286 (6)0.0284 (6)0.0225 (6)0.0128 (5)−0.0019 (5)0.0015 (5)
C90.0272 (6)0.0257 (6)0.0260 (6)0.0094 (5)0.0086 (5)0.0065 (5)
C100.0217 (5)0.0223 (6)0.0217 (5)0.0071 (4)0.0051 (4)0.0021 (4)
C110.0240 (6)0.0232 (6)0.0182 (5)0.0071 (5)0.0030 (4)0.0034 (4)
C120.0294 (6)0.0251 (6)0.0243 (6)0.0019 (5)−0.0017 (5)0.0022 (5)
C130.0358 (7)0.0217 (6)0.0281 (6)0.0046 (5)0.0050 (5)0.0056 (5)
C140.0343 (7)0.0292 (6)0.0253 (6)0.0138 (5)0.0050 (5)0.0083 (5)
C150.0256 (6)0.0290 (6)0.0224 (6)0.0099 (5)0.0003 (5)0.0036 (5)
C160.0209 (5)0.0211 (5)0.0201 (5)0.0064 (4)0.0040 (4)0.0011 (4)
C170.0225 (6)0.0314 (6)0.0229 (6)0.0092 (5)0.0002 (5)0.0048 (5)
C180.0225 (6)0.0210 (5)0.0230 (6)0.0025 (4)−0.0037 (4)0.0030 (4)
C190.0393 (7)0.0268 (6)0.0285 (6)0.0122 (5)−0.0017 (5)0.0070 (5)
C200.0543 (9)0.0395 (8)0.0271 (7)0.0124 (7)−0.0023 (6)0.0127 (6)
C210.0470 (8)0.0395 (8)0.0243 (6)0.0057 (6)0.0046 (6)0.0036 (6)
C220.0408 (8)0.0321 (7)0.0352 (7)0.0125 (6)0.0092 (6)0.0032 (6)
C230.0348 (7)0.0297 (6)0.0298 (7)0.0132 (5)0.0044 (5)0.0096 (5)
C240.0343 (6)0.0171 (5)0.0223 (6)0.0064 (5)0.0001 (5)0.0048 (4)
C250.0205 (5)0.0211 (6)0.0217 (6)0.0071 (4)0.0030 (4)0.0019 (4)
C260.0247 (6)0.0222 (6)0.0367 (7)0.0056 (5)0.0011 (5)0.0027 (5)
C270.0330 (7)0.0272 (7)0.0438 (8)0.0053 (5)−0.0093 (6)−0.0076 (6)
C280.0369 (7)0.0422 (8)0.0285 (7)0.0121 (6)−0.0081 (6)−0.0050 (6)
C290.0403 (7)0.0370 (7)0.0262 (7)0.0099 (6)−0.0040 (6)0.0077 (6)
C300.0337 (7)0.0238 (6)0.0245 (6)0.0044 (5)−0.0022 (5)0.0046 (5)
Geometric parameters (Å, °) top
O—C81.4211 (14)C13—H130.9500
O—C91.4350 (14)C14—C151.3865 (18)
N1—C71.3141 (15)C14—H140.9500
N1—C11.3907 (16)C15—C161.3985 (17)
N2—C71.3726 (15)C15—H150.9500
N2—C61.3846 (15)C17—C181.5108 (17)
N2—C241.4553 (14)C17—H17A0.9900
N3—C101.3136 (16)C17—H17B0.9900
N3—C161.3905 (15)C18—C231.3850 (18)
N4—C101.3748 (15)C18—C191.3859 (18)
N4—C111.3825 (15)C19—C201.387 (2)
N4—C171.4596 (15)C19—H190.9500
C1—C21.3996 (17)C20—C211.384 (2)
C1—C61.4056 (16)C20—H200.9500
C2—C31.3816 (18)C21—C221.383 (2)
C2—H20.9500C21—H210.9500
C3—C41.4065 (19)C22—C231.385 (2)
C3—H30.9500C22—H220.9500
C4—C51.3851 (18)C23—H230.9500
C4—H40.9500C24—C251.5134 (16)
C5—C61.3929 (17)C24—H24A0.9900
C5—H50.9500C24—H24B0.9900
C7—C81.4898 (17)C25—C301.3828 (17)
C8—H8A0.9900C25—C261.3930 (16)
C8—H8B0.9900C26—C271.382 (2)
C9—C101.4945 (17)C26—H260.9500
C9—H9A0.9900C27—C281.384 (2)
C9—H9B0.9900C27—H270.9500
C11—C121.3935 (17)C28—C291.378 (2)
C11—C161.4049 (16)C28—H280.9500
C12—C131.3811 (19)C29—C301.3938 (18)
C12—H120.9500C29—H290.9500
C13—C141.4033 (19)C30—H300.9500
C8—O—C9110.65 (9)C13—C14—H14119.2
C7—N1—C1104.47 (10)C14—C15—C16117.55 (11)
C7—N2—C6106.33 (9)C14—C15—H15121.2
C7—N2—C24128.47 (10)C16—C15—H15121.2
C6—N2—C24125.20 (10)N3—C16—C15130.02 (11)
C10—N3—C16104.83 (10)N3—C16—C11109.99 (10)
C10—N4—C11106.39 (10)C15—C16—C11119.97 (11)
C10—N4—C17127.05 (11)N4—C17—C18113.67 (10)
C11—N4—C17126.55 (10)N4—C17—H17A108.8
N1—C1—C2129.86 (11)C18—C17—H17A108.8
N1—C1—C6110.28 (10)N4—C17—H17B108.8
C2—C1—C6119.85 (11)C18—C17—H17B108.8
C3—C2—C1117.78 (11)H17A—C17—H17B107.7
C3—C2—H2121.1C23—C18—C19118.91 (12)
C1—C2—H2121.1C23—C18—C17121.38 (11)
C2—C3—C4121.34 (12)C19—C18—C17119.69 (11)
C2—C3—H3119.3C18—C19—C20120.65 (13)
C4—C3—H3119.3C18—C19—H19119.7
C5—C4—C3122.06 (12)C20—C19—H19119.7
C5—C4—H4119.0C21—C20—C19119.97 (13)
C3—C4—H4119.0C21—C20—H20120.0
C4—C5—C6116.01 (11)C19—C20—H20120.0
C4—C5—H5122.0C22—C21—C20119.69 (13)
C6—C5—H5122.0C22—C21—H21120.2
N2—C6—C5131.85 (11)C20—C21—H21120.2
N2—C6—C1105.17 (10)C21—C22—C23120.05 (14)
C5—C6—C1122.96 (11)C21—C22—H22120.0
N1—C7—N2113.75 (11)C23—C22—H22120.0
N1—C7—C8122.39 (11)C18—C23—C22120.71 (12)
N2—C7—C8123.68 (11)C18—C23—H23119.6
O—C8—C7110.75 (10)C22—C23—H23119.6
O—C8—H8A109.5N2—C24—C25114.13 (10)
C7—C8—H8A109.5N2—C24—H24A108.7
O—C8—H8B109.5C25—C24—H24A108.7
C7—C8—H8B109.5N2—C24—H24B108.7
H8A—C8—H8B108.1C25—C24—H24B108.7
O—C9—C10112.03 (10)H24A—C24—H24B107.6
O—C9—H9A109.2C30—C25—C26118.82 (11)
C10—C9—H9A109.2C30—C25—C24122.96 (11)
O—C9—H9B109.2C26—C25—C24118.21 (11)
C10—C9—H9B109.2C27—C26—C25120.48 (13)
H9A—C9—H9B107.9C27—C26—H26119.8
N3—C10—N4113.39 (11)C25—C26—H26119.8
N3—C10—C9125.14 (11)C26—C27—C28120.52 (13)
N4—C10—C9121.46 (11)C26—C27—H27119.7
N4—C11—C12131.98 (11)C28—C27—H27119.7
N4—C11—C16105.38 (10)C29—C28—C27119.31 (13)
C12—C11—C16122.64 (11)C29—C28—H28120.3
C13—C12—C11116.55 (11)C27—C28—H28120.3
C13—C12—H12121.7C28—C29—C30120.41 (13)
C11—C12—H12121.7C28—C29—H29119.8
C12—C13—C14121.68 (12)C30—C29—H29119.8
C12—C13—H13119.2C25—C30—C29120.44 (12)
C14—C13—H13119.2C25—C30—H30119.8
C15—C14—C13121.61 (12)C29—C30—H30119.8
C15—C14—H14119.2
C7—N1—C1—C2177.64 (12)C17—N4—C11—C16−178.40 (11)
C7—N1—C1—C6−0.91 (12)N4—C11—C12—C13−179.01 (13)
N1—C1—C2—C3−178.07 (12)C16—C11—C12—C130.11 (19)
C6—C1—C2—C30.35 (17)C11—C12—C13—C140.5 (2)
C1—C2—C3—C4−0.82 (18)C12—C13—C14—C15−0.4 (2)
C2—C3—C4—C50.42 (19)C13—C14—C15—C16−0.32 (19)
C3—C4—C5—C60.47 (18)C10—N3—C16—C15−178.95 (12)
C7—N2—C6—C5−178.66 (12)C10—N3—C16—C11−0.61 (13)
C24—N2—C6—C51.42 (19)C14—C15—C16—N3179.09 (12)
C7—N2—C6—C1−0.40 (12)C14—C15—C16—C110.90 (17)
C24—N2—C6—C1179.68 (10)N4—C11—C16—N3−0.03 (13)
C4—C5—C6—N2177.04 (12)C12—C11—C16—N3−179.35 (11)
C4—C5—C6—C1−0.95 (17)N4—C11—C16—C15178.50 (10)
N1—C1—C6—N20.82 (12)C12—C11—C16—C15−0.82 (18)
C2—C1—C6—N2−177.89 (10)C10—N4—C17—C1882.90 (15)
N1—C1—C6—C5179.27 (10)C11—N4—C17—C18−98.27 (14)
C2—C1—C6—C50.56 (17)N4—C17—C18—C2347.20 (16)
C1—N1—C7—N20.66 (13)N4—C17—C18—C19−134.51 (12)
C1—N1—C7—C8−174.66 (11)C23—C18—C19—C20−0.6 (2)
C6—N2—C7—N1−0.17 (13)C17—C18—C19—C20−178.91 (12)
C24—N2—C7—N1179.75 (11)C18—C19—C20—C21−0.5 (2)
C6—N2—C7—C8175.08 (10)C19—C20—C21—C220.9 (2)
C24—N2—C7—C8−5.00 (18)C20—C21—C22—C23−0.2 (2)
C9—O—C8—C7−175.36 (10)C19—C18—C23—C221.3 (2)
N1—C7—C8—O−122.70 (12)C17—C18—C23—C22179.60 (12)
N2—C7—C8—O62.45 (15)C21—C22—C23—C18−0.9 (2)
C8—O—C9—C1074.56 (13)C7—N2—C24—C25−98.23 (14)
C16—N3—C10—N41.06 (13)C6—N2—C24—C2581.68 (14)
C16—N3—C10—C9−179.86 (11)N2—C24—C25—C309.57 (17)
C11—N4—C10—N3−1.10 (14)N2—C24—C25—C26−171.39 (11)
C17—N4—C10—N3177.92 (11)C30—C25—C26—C270.00 (19)
C11—N4—C10—C9179.78 (10)C24—C25—C26—C27−179.08 (12)
C17—N4—C10—C9−1.20 (18)C25—C26—C27—C28−0.6 (2)
O—C9—C10—N3−106.11 (13)C26—C27—C28—C290.7 (2)
O—C9—C10—N472.90 (14)C27—C28—C29—C30−0.3 (2)
C10—N4—C11—C12179.86 (13)C26—C25—C30—C290.43 (19)
C17—N4—C11—C120.8 (2)C24—C25—C30—C29179.46 (13)
C10—N4—C11—C160.63 (13)C28—C29—C30—C25−0.3 (2)
Acknowledgements top

The authors acknowledge financial support and a grant from the `Qing Lan' Talent Engineering Funds and Students' Science and Technology Innovation Funds (grant No. DXS2008–040,041) of Lanzhou Jiaotong University. A grant from the Middle-Young Age Science Foundation (grant No. 3YS061-A25–023) and `Long Yuan Qing Nian' of Gansu Province is also acknowledged.

references
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