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Acta Crystallogr Sect E Struct Rep Online. 2009 July 1; 65(Pt 7): o1517–o1518.
Published online 2009 June 6. doi:  10.1107/S1600536809020844
PMCID: PMC2969417

2-(1H-Benzimidazol-1-yl)-1-(2-furyl)ethanone O-propyloxime

Abstract

In the mol­ecule of the title compound, C16H17N3O2, the planar benzimidazole ring system [maximum deviation = 0.013 (1) Å] is oriented at a dihedral angle of 75.32 (4)° with respect to the furan ring. An intra­molecular C—H(...)O inter­action results in the formation of a planar six-membered ring [maximum deviation = 0.019 (15) Å], which is oriented at a dihedral angle of 1.91 (3)° with respect to the adjacent furan ring. In the crystal structure, inter­molecular C—H(...)N inter­actions link the mol­ecules into centrosymmetric R 2 2(18) dimers. In addition, the structure is stabilized by π–π contacts between the imidazole rings [centroid–centroid distance = 3.5307 (8) Å] and weak C—H(...)π inter­actions.

Related literature

Several compounds containing an oxime or an oxime ether function have been reported to exhibit anti­microbial activity, see: Baji et al. (1995 [triangle]); Bhandari et al. (2009 [triangle]); Emami et al. (2002 [triangle], 2004 [triangle]); Milanese et al. (2007 [triangle]); Polak (1982 [triangle]); Poretta et al. (1993 [triangle]); Ramalingan et al. (2006 [triangle]); Rosello et al. (2002 [triangle]). For related structures, see: Özel Güven et al. (2007a [triangle],b [triangle]). For ring motifs, see: Bernstein et al. (1995 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o1517-scheme1.jpg

Experimental

Crystal data

  • C16H17N3O2
  • M r = 283.33
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1517-efi1.jpg
  • a = 8.4164 (2) Å
  • b = 18.2524 (3) Å
  • c = 10.2246 (2) Å
  • β = 111.354 (1)°
  • V = 1462.87 (5) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 120 K
  • 0.50 × 0.35 × 0.35 mm

Data collection

  • Bruker–Nonius Kappa CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 2007 [triangle]) T min = 0.958, T max = 0.960
  • 19714 measured reflections
  • 3344 independent reflections
  • 2755 reflections with I > 2σ(I)
  • R int = 0.038

Refinement

  • R[F 2 > 2σ(F 2)] = 0.043
  • wR(F 2) = 0.114
  • S = 1.14
  • 3344 reflections
  • 259 parameters
  • All H-atom parameters refined
  • Δρmax = 0.37 e Å−3
  • Δρmin = −0.36 e Å−3

Data collection: COLLECT (Hooft, 1998 [triangle]); cell refinement: DENZO (Otwinowski & Minor, 1997 [triangle]) and COLLECT; data reduction: DENZO nd COLLECT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]) and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809020844/ci2817sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809020844/ci2817Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors acknowledge the Zonguldak Karaelmas University Research Fund (Project No. 2007/2–13-02–09).

supplementary crystallographic information

Comment

Oxiconazole (Polak, 1982) is a well known antifungal agent with a broad spectrum of activity, used for the treatment of skin mycoses. It is structurally characterized by an oxime ether group. Several compounds containing an oxime or an oxime ether function have been reported to exhibit antimicrobial activity (Poretta et al., 1993; Baji et al., 1995; Rosello et al., 2002; Emami et al., 2002; Emami et al., 2004; Ramalingan et al., 2006; Milanese et al., 2007; Bhandari et al., 2009). In our earlier studies, we reported the crystal structure of a benzimidazole substituted oxiconazole derivative (Özel Güven et al., 2007a). Now, we report herein the crystal structure of the title alkyl oxime ether.

In the molecule of the title compound (Fig. 1), the bond lengths and angles are generally within normal ranges. The planar benzimidazole ring system is oriented with respect to the furan ring at a dihedral angle of 75.32 (4)°. Atoms O2, N3, C8, C9, C14 and C15 are 0.073 (1), 0.024 (1), -0.064 (1), -0.009 (1), 0.088 (1) and -0.082 (1) Å away from the furan ring plane, respectively, while atom C8 is at a distance of -0.007 (1) Å to the benzimidazole ring plane. So, they are coplanar with the adjacent rings. The N1—C1—N2 [114.29 (11)°], N2—C2—C7 [110.24 (11)°] and C2—C7—C6 [122.57 (11)°] bond angles are enlarged, while C5—C6—C7 [116.36 (11)°] and C2—C3—C4 [117.87 (11)°] bond angles are narrowed. An intramolecular C—H···O interaction (Table 1) results in the formation of a planar six-membered ring, (O2/N3/C9—C11/H11), which is oriented with respect to the adjacent furan ring at a dihedral angle of 1.91 (3)°. So, they are almost coplanar.

In the crystal structure, intermolecular C—H···N interactions (Table 1) link the molecules into centrosymmetric dimers through R22(18) ring motifs (Bernstein et al., 1995) (Fig. 2), in which they may be effective in the stabilization of the structure. The π···π contact between the benzimidazole rings [Cg2···Cg2i = 3.5307 (8) Å, where Cg1 is centroid of the N1/N2/C1/C2/C7 ring; symmetry code: (i) 2 - x, 1 -y, 2 - z] may further stabilize the structure. There also exist three weak C—H···π interactions (Table 1).

Experimental

The title compound was synthesized by the reaction of 2-(1H-benzimidazol-1-yl)-1-(furan-2-yl)ethanone oxime obtained from 2-(1H-benzimidazol-1-yl)-1-(furan-2-yl)ethanone (Özel Güven et al., 2007b) with n-propyl bromide and NaH. To a solution of 2-(1H-benzimidazol-1-yl)-1-(furan-2-yl)ethanone oxime (350 mg, 1.451 mmol) in DMF (5 ml) was added NaH (58 mg, 1.451 mmol) in small fractions. Then, n-propyl bromide (178 mg, 1.451 mmol) was added dropwise. The mixture was stirred at room temperature for 3 h and the excess of hydride was decomposed with a small amount of methyl alcohol. After evaporation to dryness under reduced pressure, the crude residue was suspended with water and extracted with methylene chloride. The organic layer was dried over anhydrous sodium sulfate and then evaporated to dryness. The crude product was purified by chromatography on a silica-gel column using chloroform and recrystallized from hexane-ethyl acetate (1:3) mixture to obtain pale-yellowish crystals (yield 150 mg, 37%).

Refinement

H atoms were located in a difference map and were refined isotropically [C—H = 0.959 (15)–1.015 (17) Å and Uiso(H) = 0.018 (3)–0.048 (5) Å2].

Figures

Fig. 1.
The molecular structure of the title compound, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. The dashed line indicates a hydrogen bond.
Fig. 2.
A partial packing diagram of the title compound. Hydrogen bonds are shown as dashed lines. H atoms not involved in hydrogen bonding have been omitted for clarity.

Crystal data

C16H17N3O2F(000) = 600
Mr = 283.33Dx = 1.286 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3395 reflections
a = 8.4164 (2) Åθ = 2.9–27.5°
b = 18.2524 (3) ŵ = 0.09 mm1
c = 10.2246 (2) ÅT = 120 K
β = 111.354 (1)°Block, pale yellow
V = 1462.87 (5) Å30.50 × 0.35 × 0.35 mm
Z = 4

Data collection

Bruker–Nonius Kappa CCD diffractometer3344 independent reflections
Radiation source: fine-focus sealed tube2755 reflections with I > 2σ(I)
graphiteRint = 0.038
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 2.9°
[var phi] & ω scansh = −10→10
Absorption correction: multi-scan (SADABS; Sheldrick, 2007)k = −23→23
Tmin = 0.958, Tmax = 0.960l = −13→13
19714 measured reflections

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.043All H-atom parameters refined
wR(F2) = 0.114w = 1/[σ2(Fo2) + (0.0594P)2 + 0.2758P] where P = (Fo2 + 2Fc2)/3
S = 1.14(Δ/σ)max = 0.001
3344 reflectionsΔρmax = 0.37 e Å3
259 parametersΔρmin = −0.36 e Å3
0 restraintsExtinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.065 (5)

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 (Å2)

xyzUiso*/Ueq
O10.43354 (11)0.47469 (5)0.69234 (9)0.0210 (2)
O20.62124 (10)0.35487 (5)0.44862 (9)0.0215 (2)
N10.81649 (13)0.45397 (6)0.87655 (10)0.0191 (2)
N20.81640 (14)0.44200 (6)1.09515 (11)0.0234 (3)
N30.73483 (13)0.39962 (6)0.55091 (11)0.0203 (2)
C10.75737 (16)0.47823 (7)0.97642 (13)0.0226 (3)
H10.680 (2)0.5192 (8)0.9590 (16)0.025 (4)*
C20.92279 (15)0.38916 (7)1.07227 (12)0.0196 (3)
C31.01939 (16)0.33471 (7)1.16205 (13)0.0229 (3)
H31.016 (2)0.3284 (9)1.2569 (17)0.034 (4)*
C41.11688 (16)0.28954 (7)1.11299 (14)0.0250 (3)
H41.185 (2)0.2500 (9)1.1699 (17)0.035 (4)*
C51.11963 (16)0.29780 (7)0.97705 (14)0.0249 (3)
H51.192 (2)0.2655 (9)0.9461 (16)0.033 (4)*
C61.02292 (16)0.35075 (7)0.88540 (13)0.0223 (3)
H61.0243 (19)0.3573 (8)0.7909 (16)0.026 (4)*
C70.92492 (15)0.39601 (6)0.93600 (12)0.0180 (3)
C80.77611 (17)0.48381 (7)0.73516 (13)0.0209 (3)
H810.8843 (18)0.4894 (8)0.7176 (14)0.018 (3)*
H820.7235 (19)0.5324 (8)0.7319 (15)0.021 (4)*
C90.65977 (15)0.43432 (6)0.62241 (12)0.0177 (3)
C100.48021 (15)0.42984 (6)0.60389 (12)0.0176 (3)
C110.34138 (16)0.39130 (7)0.52080 (13)0.0195 (3)
H110.3406 (18)0.3571 (8)0.4478 (15)0.024 (4)*
C120.20149 (17)0.41338 (7)0.55880 (14)0.0228 (3)
H120.081 (2)0.3957 (8)0.5195 (16)0.027 (4)*
C130.26348 (17)0.46348 (7)0.66207 (13)0.0233 (3)
H130.2152 (18)0.4915 (8)0.7179 (15)0.021 (3)*
C140.71245 (17)0.31673 (8)0.37379 (15)0.0269 (3)
H1410.813 (2)0.2925 (9)0.4441 (17)0.032 (4)*
H1420.749 (2)0.3531 (9)0.3176 (17)0.034 (4)*
C150.59066 (18)0.26057 (8)0.28123 (14)0.0278 (3)
H1510.650 (2)0.2349 (10)0.2257 (17)0.040 (4)*
H1520.493 (2)0.2866 (9)0.2113 (18)0.040 (5)*
C160.52829 (18)0.20602 (8)0.36374 (15)0.0287 (3)
H1610.624 (2)0.1794 (10)0.4348 (19)0.048 (5)*
H1620.468 (2)0.2317 (9)0.4205 (16)0.036 (4)*
H1630.449 (2)0.1687 (10)0.3015 (19)0.047 (5)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0239 (5)0.0207 (4)0.0187 (4)0.0014 (3)0.0082 (4)−0.0027 (3)
O20.0178 (4)0.0252 (5)0.0212 (4)−0.0019 (3)0.0069 (4)−0.0078 (4)
N10.0206 (5)0.0191 (5)0.0163 (5)−0.0009 (4)0.0052 (4)−0.0009 (4)
N20.0248 (6)0.0258 (6)0.0187 (5)0.0015 (4)0.0066 (4)−0.0034 (4)
N30.0201 (5)0.0212 (5)0.0169 (5)−0.0026 (4)0.0036 (4)−0.0013 (4)
C10.0234 (6)0.0223 (6)0.0213 (6)0.0001 (5)0.0070 (5)−0.0053 (5)
C20.0179 (6)0.0221 (6)0.0173 (6)−0.0037 (5)0.0047 (5)−0.0036 (5)
C30.0202 (6)0.0275 (7)0.0185 (6)−0.0021 (5)0.0041 (5)0.0012 (5)
C40.0191 (6)0.0252 (7)0.0261 (7)0.0017 (5)0.0026 (5)0.0025 (5)
C50.0187 (6)0.0264 (7)0.0293 (7)0.0016 (5)0.0083 (5)−0.0036 (5)
C60.0200 (6)0.0266 (6)0.0212 (6)−0.0027 (5)0.0086 (5)−0.0022 (5)
C70.0155 (5)0.0188 (6)0.0178 (6)−0.0035 (4)0.0036 (5)−0.0016 (4)
C80.0238 (6)0.0200 (6)0.0165 (6)−0.0042 (5)0.0045 (5)0.0009 (5)
C90.0206 (6)0.0161 (6)0.0150 (6)−0.0009 (4)0.0050 (5)0.0029 (4)
C100.0229 (6)0.0157 (5)0.0146 (5)0.0013 (4)0.0074 (5)0.0010 (4)
C110.0219 (6)0.0185 (6)0.0181 (6)−0.0005 (5)0.0073 (5)−0.0001 (5)
C120.0216 (6)0.0240 (6)0.0237 (6)0.0010 (5)0.0093 (5)0.0018 (5)
C130.0235 (6)0.0257 (6)0.0235 (6)0.0045 (5)0.0116 (5)0.0020 (5)
C140.0212 (7)0.0350 (7)0.0277 (7)0.0011 (6)0.0128 (6)−0.0079 (6)
C150.0249 (7)0.0354 (8)0.0232 (6)0.0032 (6)0.0087 (6)−0.0095 (6)
C160.0258 (7)0.0267 (7)0.0305 (7)0.0041 (6)0.0067 (6)−0.0070 (6)

Geometric parameters (Å, °)

O1—C101.3787 (14)C6—H60.978 (15)
O1—C131.3652 (16)C8—H810.996 (14)
O2—N31.3952 (13)C8—H820.987 (15)
O2—C141.4447 (15)C9—C81.5105 (16)
N1—C11.3625 (16)C9—C101.4553 (16)
N1—C71.3847 (15)C11—C101.3635 (17)
N1—C81.4643 (15)C11—C121.4257 (17)
N2—C11.3110 (17)C11—H110.971 (15)
N2—C21.3927 (16)C12—H120.999 (16)
N3—C91.2927 (16)C13—C121.3499 (19)
C1—H10.963 (15)C13—H130.959 (15)
C2—C31.3956 (18)C14—H1410.994 (16)
C2—C71.4055 (17)C14—H1420.999 (17)
C3—H30.987 (16)C15—C141.5136 (19)
C4—C31.3800 (18)C15—C161.517 (2)
C4—C51.4066 (19)C15—H1510.999 (17)
C4—H40.973 (17)C15—H1520.994 (18)
C5—H50.982 (16)C16—H1610.993 (19)
C6—C51.3854 (18)C16—H1621.015 (17)
C6—C71.3933 (17)C16—H1631.001 (19)
C13—O1—C10106.73 (9)N3—C9—C10126.66 (11)
N3—O2—C14109.14 (9)N3—C9—C8114.21 (11)
C1—N1—C7106.35 (10)C10—C9—C8119.13 (10)
C1—N1—C8127.02 (11)C11—C10—O1109.32 (10)
C7—N1—C8126.62 (10)C11—C10—C9136.37 (11)
C1—N2—C2104.12 (10)O1—C10—C9114.31 (10)
C9—N3—O2111.61 (10)C10—C11—C12106.84 (11)
N1—C1—H1121.3 (9)C10—C11—H11125.1 (9)
N2—C1—N1114.29 (11)C12—C11—H11128.0 (9)
N2—C1—H1124.4 (9)C13—C12—C11106.40 (11)
N2—C2—C3129.71 (11)C13—C12—H12125.5 (9)
N2—C2—C7110.24 (11)C11—C12—H12128.1 (9)
C3—C2—C7120.05 (11)C12—C13—O1110.70 (11)
C4—C3—C2117.87 (11)C12—C13—H13134.4 (9)
C4—C3—H3121.4 (10)O1—C13—H13114.9 (9)
C2—C3—H3120.7 (10)O2—C14—C15106.74 (10)
C3—C4—C5121.40 (12)O2—C14—H142108.7 (9)
C3—C4—H4121.7 (9)C15—C14—H142111.9 (9)
C5—C4—H4116.9 (9)O2—C14—H141108.0 (9)
C6—C5—C4121.75 (12)C15—C14—H141110.9 (9)
C6—C5—H5118.9 (9)H142—C14—H141110.5 (13)
C4—C5—H5119.4 (9)C14—C15—C16112.93 (11)
C5—C6—C7116.36 (11)C14—C15—H151107.9 (10)
C5—C6—H6122.6 (9)C16—C15—H151110.7 (10)
C7—C6—H6121.1 (9)C14—C15—H152108.7 (10)
N1—C7—C6132.42 (11)C16—C15—H152110.5 (10)
N1—C7—C2105.01 (10)H151—C15—H152105.7 (13)
C6—C7—C2122.57 (11)C15—C16—H161112.0 (10)
N1—C8—C9112.58 (9)C15—C16—H162111.2 (9)
N1—C8—H81108.5 (8)H161—C16—H162104.4 (13)
C9—C8—H81107.8 (8)C15—C16—H163112.1 (10)
N1—C8—H82108.0 (8)H161—C16—H163107.8 (15)
C9—C8—H82110.7 (9)H162—C16—H163108.8 (14)
H81—C8—H82109.2 (12)
C13—O1—C10—C11−0.29 (13)N2—C2—C7—N1−0.36 (13)
C13—O1—C10—C9−179.60 (10)C3—C2—C7—N1179.63 (11)
C10—O1—C13—C120.20 (13)N2—C2—C7—C6179.04 (11)
C14—O2—N3—C9−179.10 (10)C3—C2—C7—C6−0.97 (18)
N3—O2—C14—C15171.16 (10)C5—C4—C3—C20.06 (19)
C7—N1—C1—N20.07 (15)C3—C4—C5—C6−1.0 (2)
C8—N1—C1—N2−179.00 (11)C7—C6—C5—C40.93 (18)
C1—N1—C7—C6−179.14 (13)C5—C6—C7—N1179.26 (12)
C8—N1—C7—C6−0.1 (2)C5—C6—C7—C20.05 (18)
C1—N1—C7—C20.18 (13)N3—C9—C8—N1−106.07 (12)
C8—N1—C7—C2179.25 (11)C10—C9—C8—N173.98 (14)
C1—N1—C8—C9−107.61 (14)N3—C9—C10—C112.8 (2)
C7—N1—C8—C973.51 (15)C8—C9—C10—C11−177.25 (13)
C2—N2—C1—N1−0.28 (14)N3—C9—C10—O1−178.13 (11)
C1—N2—C2—C3−179.59 (13)C8—C9—C10—O11.81 (15)
C1—N2—C2—C70.39 (13)C12—C11—C10—O10.26 (13)
O2—N3—C9—C10−0.07 (16)C12—C11—C10—C9179.35 (13)
O2—N3—C9—C8179.98 (9)C10—C11—C12—C13−0.13 (14)
N2—C2—C3—C4−179.13 (12)O1—C13—C12—C11−0.04 (14)
C7—C2—C3—C40.89 (18)C16—C15—C14—O2−59.43 (15)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C11—H11···O20.97 (2)2.359 (16)2.7930 (17)106 (1)
C13—H13···N2i0.96 (2)2.360 (15)3.2872 (17)162 (1)
C14—H141···Cg1ii0.99 (2)2.968 (17)3.8346 (16)146 (1)
C16—H161···Cg2ii0.99 (2)2.685 (18)3.5644 (16)148 (1)
C16—H163···Cg3ii1.00 (2)2.643 (18)3.5901 (15)157 (1)

Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) x, −y−1/2, z−3/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: CI2817).

References

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