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Acta Cryst. (2009). E65, o2216    [ doi:10.1107/S1600536809032899 ]

6-(2-Hydroxyphenyl)-5,6-dihydrobenzimidazolo[1,2-c]quinazolin-12-ium bromide ethanol solvate

I. Booysen, T. I. A. Gerber, E. Hosten and P. Mayer

Abstract top

In the title compound, C20H16N3O+·Br-·C2H6O, the phenol ring forms dihedral angles of 84.5 (1) and 89.3 (1)° with the benzimidazole system and the quinazoline benzene ring, respectively. The two N-H groups act as donors in hydrogen bonds with the bromide ion as acceptor, leading to infinite eight-membered chains along [100]. According to graph-set theory the descriptor on the binary level is C21(8). O-H...O and O-H...Br hydrogen bonds also occur.

Comment top

In the present work the structure of 2-(tetrahydrobenzimidazolium[1,2-c]quinazolin-5-yl)phenol bromide has been determined to explore its suitability as a bidentate ligand for various metal ions. In the structure the quinazoline ring adopts a chair conformation: atoms C8, C13, C14, N1 and N2 are coplanar, with atom C7 from the plane by 0.178 Å (Figure 1). The orientation of the phenol ring is determined by a hydrogen-bond between the phenolic oxygen atom and the ethanolic oxygen atom. This ring makes dihedral angles of 84.5° and 89.3° with the benzimidazole and phenyl rings respectively. The ligand bond distances and angles show that N3–C14 is a localized double bond [1.337 (3) Å], with N2–C15 a single bond at 1.398 (3) Å. N3 is protonated, with the C14–N3–C16 bond angle equal to 109.30 (17)°. The N1–C7 bond length is 1.452 (3) Å, and the N1–C7–N2 bond angle [107.71 (16)°] illustrates the sp3 hybridization of C7.

The molecular packing of the title compound is shown in Figure 2. A feature of the structure is parallel stacking of the 5-membered ring N2—C14—N3—C16—C15 and the 6-membered ring C15—C16—C17—C18—C19—C20. These planes have an interplanar angle of 0.45 (11)° and an interplanar distance of 3.4118 (8) Å.

The two O–H groups and the two N–H groups act as donors in four different hydrogen bonds, three of them with bromide as acceptor and one of them with the ethanolic oxygen atom as acceptor. In terms of graph set analysis (Etter et al., 1990; Bernstein et al., 1995), three extended hydrogen bond patterns may be selected and characterized by graph set descriptors. 8-membered chains along [100] are formed by the two hydrogen bonds of the type N–H···Br (graph set descriptor C12(8) on the binary level, Figure 3). A 20-membered ring and a 24-membered ring are formed by six hydrogen bonds within two formula units (Figures 4 and 5). The graph set descriptors R46(20) and R46(24), respectively, can be assigned on the ternary level.

Related literature top

For the synthesis of quinazolines, see: Kubicova et al. (2003); Niementowski (1895). For related literature, see: Cuny et al. (1980); Williamson (1957). For graph-set analysis, see: Bernstein et al. (1995); Etter et al. (1990).

Experimental top

All chemicals used (reagent grade) were commercially available. A mass of 0.0244 g (200 µmol) of 2-aminobenzaldehyde was dissolved in methanol (10 cm3), and 0.0418 g (200 µmol) of 2-(2-aminophenyl)-1-benzimidazole was added with stirring. After the mixture was heated under reflux for 30 min, a mass of 0.096 g (100 µmol) of trans-[ReOBr3(PPh3)2] was added, and heating was continued for a further 30 min. After cooling to room temperature, the solution was filtered and left to evaporate slowly at room temperature. After 2 days 0.063 g (72%) of colourless crystals, with the formulation [C20H16N3O]Br.C2H6O and suitable for X-ray analysis, were collected. M.p. 211°C. 1H NMR (300 MHz, d6-DMSO): 14.71 (1H, br s), 8.62 (1H,d), 8.58 (1H, d), 8.18 (1H, s), 8.04–8.09 (2H, m), 7.72–7.82 (3H, m), 7.68 (1H, dd), 7.42–7.48 (2H, m), 7.28 (1H, t), 7.19 (1H, t), 7.06 (1H, d), 3.42 (2H, q), 1.23 (3H, t). IR (KBr, cm-1): ν(OH) 3460w, ν(NH) 3275, ν(C=N) 1603 s.

Refinement top

The H atoms were positioned geometrically (C—H = 0.98 Å for CH3, 0.99 Å for CH2, 0.95 Å for CH, 0.84 Å for OH, 0.88 Å for NH) and treated as riding on their parent atoms [Uiso(H) = 1.2Ueq(C/N) for CH and NH, Uiso(H) = 1.5Ueq(C/O) for CH3 and OH].

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: PARST (Nardelli, 1995) and publCIF (Westrip, 20091).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound (anisotropic displacement ellipsoids drawn at the 50% probablility level).
[Figure 2] Fig. 2. The packing of the title compound, viewed along [-100].
[Figure 3] Fig. 3. The hydrogen bonds leading to infinite 8-membered chains along [100]. b: N1–H71···Br1, c: N3–H73···Br1.
[Figure 4] Fig. 4. The hydrogen bonds leading to 20-membered rings. a: O1–H1···O2, b: N1–H71···Br1, d: O2–H2···Br1.
[Figure 5] Fig. 5. The hydrogen bonds leading to 24-membered rings. a: O1–H1···O2, c: N3–H73···Br1, d: O2–H2···Br1.
6-(2-Hydroxyphenyl)-5,6-dihydrobenzimidazolo[1,2-c]quinazolin-12-ium bromide ethanol solvate top
Crystal data top
C20H16N3O+·Br−·C2H6OF(000) = 452
Mr = 440.33Dx = 1.476 (1) Mg m−3
Triclinic, P1Melting point: 484 K
a = 9.3438 (5) ÅMo Kα radiation, λ = 0.71073 Å
b = 10.0736 (5) ÅCell parameters from 3249 reflections
c = 10.8452 (5) Åθ = 3.9–26.3°
α = 86.832 (4)°µ = 2.10 mm−1
β = 77.203 (4)°T = 200 K
γ = 84.674 (4)°Platelet, yellow
V = 990.53 (9) Å30.28 × 0.24 × 0.05 mm
Z = 2
Data collection top
Oxford XCalibur
diffractometer		4004 independent reflections
Radiation source: fine-focus sealed tube2664 reflections with I > 2σ(I)
graphiteRint = 0.030
Detector resolution: 15.9809 pixels mm-1θmax = 26.3°, θmin = 3.9°
ω scansh = −11→11
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2006)		k = −12→12
Tmin = 0.783, Tmax = 1.000l = −13→12
7695 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.057H-atom parameters constrained
S = 0.84 w = 1/[σ2(Fo2) + (0.0232P)2]
where P = (Fo2 + 2Fc2)/3
4004 reflections(Δ/σ)max = 0.001
256 parametersΔρmax = 0.60 e Å−3
0 restraintsΔρmin = −0.35 e Å−3
Crystal data top
C20H16N3O+·Br−·C2H6Oγ = 84.674 (4)°
Mr = 440.33V = 990.53 (9) Å3
Triclinic, P1Z = 2
a = 9.3438 (5) ÅMo Kα radiation
b = 10.0736 (5) ŵ = 2.10 mm−1
c = 10.8452 (5) ÅT = 200 K
α = 86.832 (4)°0.28 × 0.24 × 0.05 mm
β = 77.203 (4)°
Data collection top
Oxford XCalibur
diffractometer		4004 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2006)		2664 reflections with I > 2σ(I)
Tmin = 0.783, Tmax = 1.000Rint = 0.030
7695 measured reflectionsθmax = 26.3°
Refinement top
R[F2 > 2σ(F2)] = 0.034H-atom parameters constrained
wR(F2) = 0.057Δρmax = 0.60 e Å−3
S = 0.84Δρmin = −0.35 e Å−3
4004 reflectionsAbsolute structure: ?
256 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Experimental. CrysAlis RED, Oxford Diffraction Ltd., Version 1.171.32.29 (release 10-06-2008 CrysAlis171 .NET) (compiled Jun 10 2008,16:49:55) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.29606 (17)0.74651 (15)0.40530 (15)0.0371 (4)
H10.29970.70260.47280.056*
N10.14604 (19)0.98882 (17)0.28625 (17)0.0320 (5)
H710.05041.00430.29300.038*
N20.38107 (18)0.90626 (17)0.17422 (16)0.0253 (4)
N30.59036 (18)0.96092 (17)0.20465 (17)0.0281 (5)
H730.65510.99640.23780.034*
C10.2175 (2)0.6833 (2)0.3382 (2)0.0261 (5)
C20.1706 (2)0.5575 (2)0.3723 (2)0.0314 (6)
H2A0.19380.51160.44520.038*
C30.0906 (2)0.4986 (2)0.3012 (2)0.0388 (6)
H30.05730.41290.32640.047*
C40.0583 (3)0.5626 (2)0.1941 (2)0.0394 (6)
H40.00400.52110.14470.047*
C50.1056 (2)0.6874 (2)0.1593 (2)0.0324 (6)
H50.08420.73130.08480.039*
C60.1839 (2)0.7507 (2)0.2306 (2)0.0243 (5)
C70.2219 (2)0.8922 (2)0.1944 (2)0.0248 (5)
H70.19180.91710.11270.030*
C80.2073 (2)1.0582 (2)0.3632 (2)0.0268 (5)
C90.1194 (2)1.1389 (2)0.4568 (2)0.0339 (6)
H90.01531.14540.46780.041*
C100.1830 (3)1.2084 (2)0.5323 (2)0.0393 (6)
H100.12181.26220.59570.047*
C110.3347 (3)1.2023 (2)0.5187 (2)0.0369 (6)
H110.37691.25110.57210.044*
C120.4231 (3)1.1247 (2)0.4269 (2)0.0329 (6)
H120.52701.12010.41630.039*
C130.3605 (2)1.0524 (2)0.3490 (2)0.0251 (5)
C140.4443 (2)0.9756 (2)0.2468 (2)0.0249 (5)
C150.4906 (2)0.8449 (2)0.0805 (2)0.0234 (5)
C160.6239 (2)0.8808 (2)0.1001 (2)0.0248 (5)
C170.7569 (2)0.8389 (2)0.0233 (2)0.0300 (6)
H170.84750.86460.03640.036*
C180.7518 (2)0.7580 (2)−0.0733 (2)0.0337 (6)
H180.84110.7264−0.12800.040*
C190.6187 (3)0.7212 (2)−0.0929 (2)0.0337 (6)
H190.61990.6650−0.16070.040*
C200.4854 (2)0.7640 (2)−0.0169 (2)0.0315 (6)
H200.39480.7391−0.03070.038*
O20.7042 (2)0.38247 (17)0.37419 (15)0.0512 (5)
H20.75450.32860.32190.077*
C210.5862 (3)0.4457 (3)0.3245 (3)0.0556 (8)
H21A0.52520.50620.38800.067*
H21B0.52360.37710.30920.067*
C220.6360 (3)0.5233 (3)0.2049 (3)0.0656 (9)
H22A0.70030.59010.21880.098*
H22B0.55030.56830.17740.098*
H22C0.69050.46300.13960.098*
Br10.85598 (3)0.14400 (3)0.18829 (3)0.04163 (10)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0462 (10)0.0364 (10)0.0337 (11)−0.0104 (8)−0.0197 (9)0.0112 (8)
N10.0167 (10)0.0352 (12)0.0412 (13)0.0017 (9)−0.0023 (9)0.0008 (10)
N20.0197 (10)0.0283 (11)0.0270 (12)−0.0017 (8)−0.0045 (9)0.0048 (9)
N30.0191 (10)0.0346 (12)0.0317 (13)−0.0045 (8)−0.0079 (9)0.0041 (9)
C10.0221 (12)0.0280 (14)0.0274 (15)−0.0020 (10)−0.0036 (11)−0.0022 (11)
C20.0353 (14)0.0265 (14)0.0296 (16)0.0007 (11)−0.0032 (12)0.0029 (11)
C30.0381 (15)0.0302 (15)0.0441 (18)−0.0069 (12)0.0013 (13)−0.0007 (13)
C40.0369 (15)0.0384 (16)0.0452 (19)−0.0079 (12)−0.0097 (13)−0.0103 (13)
C50.0271 (13)0.0407 (16)0.0291 (15)−0.0014 (12)−0.0064 (11)0.0007 (12)
C60.0170 (12)0.0280 (13)0.0257 (15)−0.0013 (10)−0.0007 (10)0.0020 (11)
C70.0168 (12)0.0326 (14)0.0238 (14)−0.0003 (10)−0.0044 (10)0.0065 (11)
C80.0299 (14)0.0212 (13)0.0265 (15)−0.0022 (11)−0.0027 (11)0.0084 (11)
C90.0248 (13)0.0294 (14)0.0409 (17)0.0003 (11)0.0037 (12)0.0067 (12)
C100.0484 (17)0.0286 (15)0.0329 (16)0.0009 (12)0.0072 (13)−0.0028 (12)
C110.0421 (16)0.0345 (15)0.0332 (17)−0.0057 (12)−0.0056 (13)−0.0005 (12)
C120.0300 (14)0.0313 (15)0.0363 (16)−0.0045 (11)−0.0060 (12)0.0068 (12)
C130.0253 (13)0.0246 (13)0.0221 (14)−0.0006 (10)−0.0002 (10)0.0052 (11)
C140.0201 (13)0.0257 (13)0.0269 (15)−0.0018 (10)−0.0034 (11)0.0093 (11)
C150.0214 (12)0.0229 (13)0.0226 (14)0.0005 (10)0.0000 (10)0.0055 (10)
C160.0268 (13)0.0240 (13)0.0224 (15)−0.0012 (10)−0.0044 (11)0.0052 (11)
C170.0221 (13)0.0276 (14)0.0382 (16)0.0000 (10)−0.0044 (11)0.0055 (12)
C180.0287 (14)0.0324 (15)0.0333 (16)0.0033 (11)0.0041 (11)0.0043 (12)
C190.0407 (16)0.0338 (15)0.0255 (15)−0.0018 (12)−0.0043 (12)−0.0042 (11)
C200.0258 (14)0.0369 (15)0.0329 (16)−0.0051 (11)−0.0096 (12)0.0059 (12)
O20.0656 (13)0.0575 (13)0.0339 (12)−0.0002 (10)−0.0217 (10)0.0040 (9)
C210.064 (2)0.0533 (19)0.050 (2)−0.0028 (15)−0.0179 (16)0.0123 (16)
C220.086 (2)0.0533 (19)0.060 (2)−0.0077 (17)−0.0255 (18)0.0227 (17)
Br10.02457 (14)0.04927 (18)0.0522 (2)−0.00537 (11)−0.01119 (12)0.00401 (13)
Geometric parameters (Å, °) top
O1—C11.360 (2)C9—H90.9500
O1—H10.8400C10—C111.388 (3)
N1—C81.365 (3)C10—H100.9500
N1—C71.452 (3)C11—C121.373 (3)
N1—H710.8800C11—H110.9500
N2—C141.342 (3)C12—C131.397 (3)
N2—C151.398 (3)C12—H120.9500
N2—C71.474 (2)C13—C141.427 (3)
N3—C141.336 (2)C15—C201.381 (3)
N3—C161.390 (3)C15—C161.392 (3)
N3—H730.8800C16—C171.379 (3)
C1—C21.383 (3)C17—C181.373 (3)
C1—C61.398 (3)C17—H170.9500
C2—C31.376 (3)C18—C191.393 (3)
C2—H2A0.9500C18—H180.9500
C3—C41.376 (3)C19—C201.380 (3)
C3—H30.9500C19—H190.9500
C4—C51.377 (3)C20—H200.9500
C4—H40.9500O2—C211.416 (3)
C5—C61.390 (3)O2—H20.8400
C5—H50.9500C21—C221.482 (3)
C6—C71.511 (3)C21—H21A0.9900
C7—H71.0000C21—H21B0.9900
C8—C91.401 (3)C22—H22A0.9800
C8—C131.402 (3)C22—H22B0.9800
C9—C101.367 (3)C22—H22C0.9800
?···??
C1—O1—H1109.5C12—C11—C10119.2 (2)
C8—N1—C7126.93 (17)C12—C11—H11120.4
C8—N1—H71116.5C10—C11—H11120.4
C7—N1—H71116.5C11—C12—C13120.2 (2)
C14—N2—C15109.14 (17)C11—C12—H12119.9
C14—N2—C7125.15 (18)C13—C12—H12119.9
C15—N2—C7125.64 (18)C12—C13—C8120.6 (2)
C14—N3—C16109.31 (18)C12—C13—C14123.8 (2)
C14—N3—H73125.3C8—C13—C14115.6 (2)
C16—N3—H73125.3N3—C14—N2108.79 (19)
O1—C1—C2122.8 (2)N3—C14—C13128.8 (2)
O1—C1—C6117.34 (19)N2—C14—C13122.39 (19)
C2—C1—C6119.9 (2)C20—C15—C16121.4 (2)
C3—C2—C1120.3 (2)C20—C15—N2132.57 (19)
C3—C2—H2A119.8C16—C15—N2106.04 (19)
C1—C2—H2A119.8C17—C16—N3131.3 (2)
C2—C3—C4120.7 (2)C17—C16—C15122.0 (2)
C2—C3—H3119.7N3—C16—C15106.71 (19)
C4—C3—H3119.7C18—C17—C16116.6 (2)
C3—C4—C5119.2 (2)C18—C17—H17121.7
C3—C4—H4120.4C16—C17—H17121.7
C5—C4—H4120.4C17—C18—C19121.6 (2)
C4—C5—C6121.5 (2)C17—C18—H18119.2
C4—C5—H5119.3C19—C18—H18119.2
C6—C5—H5119.3C20—C19—C18121.9 (2)
C5—C6—C1118.4 (2)C20—C19—H19119.0
C5—C6—C7119.27 (19)C18—C19—H19119.0
C1—C6—C7122.17 (19)C19—C20—C15116.5 (2)
N1—C7—N2107.70 (17)C19—C20—H20121.8
N1—C7—C6113.67 (17)C15—C20—H20121.8
N2—C7—C6112.43 (15)C21—O2—H2109.5
N1—C7—H7107.6O2—C21—C22113.1 (2)
N2—C7—H7107.6O2—C21—H21A109.0
C6—C7—H7107.6C22—C21—H21A109.0
N1—C8—C9121.2 (2)O2—C21—H21B109.0
N1—C8—C13120.7 (2)C22—C21—H21B109.0
C9—C8—C13118.2 (2)H21A—C21—H21B107.8
C10—C9—C8120.3 (2)C21—C22—H22A109.5
C10—C9—H9119.9C21—C22—H22B109.5
C8—C9—H9119.9H22A—C22—H22B109.5
C9—C10—C11121.6 (2)C21—C22—H22C109.5
C9—C10—H10119.2H22A—C22—H22C109.5
C11—C10—H10119.2H22B—C22—H22C109.5
O1—C1—C2—C3179.6 (2)C9—C8—C13—C120.4 (3)
C6—C1—C2—C3−0.3 (3)N1—C8—C13—C142.8 (3)
C1—C2—C3—C41.2 (3)C9—C8—C13—C14−176.06 (19)
C2—C3—C4—C5−0.8 (3)C16—N3—C14—N20.7 (2)
C3—C4—C5—C6−0.6 (3)C16—N3—C14—C13−177.9 (2)
C4—C5—C6—C11.5 (3)C15—N2—C14—N3−0.4 (2)
C4—C5—C6—C7−174.82 (19)C7—N2—C14—N3176.86 (17)
O1—C1—C6—C5179.06 (19)C15—N2—C14—C13178.27 (18)
C2—C1—C6—C5−1.0 (3)C7—N2—C14—C13−4.4 (3)
O1—C1—C6—C7−4.7 (3)C12—C13—C14—N3−2.1 (3)
C2—C1—C6—C7175.17 (19)C8—C13—C14—N3174.23 (19)
C8—N1—C7—N2−14.3 (3)C12—C13—C14—N2179.4 (2)
C8—N1—C7—C6110.9 (2)C8—C13—C14—N2−4.2 (3)
C14—N2—C7—N112.6 (3)C14—N2—C15—C20−179.8 (2)
C15—N2—C7—N1−170.59 (17)C7—N2—C15—C202.9 (4)
C14—N2—C7—C6−113.4 (2)C14—N2—C15—C16−0.1 (2)
C15—N2—C7—C663.4 (2)C7—N2—C15—C16−177.31 (17)
C5—C6—C7—N1112.5 (2)C14—N3—C16—C17178.9 (2)
C1—C6—C7—N1−63.7 (2)C14—N3—C16—C15−0.8 (2)
C5—C6—C7—N2−124.8 (2)C20—C15—C16—C170.6 (3)
C1—C6—C7—N259.0 (3)N2—C15—C16—C17−179.22 (19)
C7—N1—C8—C9−173.6 (2)C20—C15—C16—N3−179.71 (19)
C7—N1—C8—C137.6 (3)N2—C15—C16—N30.5 (2)
N1—C8—C9—C10−179.5 (2)N3—C16—C17—C18179.6 (2)
C13—C8—C9—C10−0.7 (3)C15—C16—C17—C18−0.8 (3)
C8—C9—C10—C110.4 (3)C16—C17—C18—C190.5 (3)
C9—C10—C11—C120.1 (3)C17—C18—C19—C200.1 (3)
C10—C11—C12—C13−0.4 (3)C18—C19—C20—C15−0.3 (3)
C11—C12—C13—C80.1 (3)C16—C15—C20—C190.0 (3)
C11—C12—C13—C14176.3 (2)N2—C15—C20—C19179.8 (2)
N1—C8—C13—C12179.27 (19)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i0.841.822.657 (2)175
N1—H71···Br1ii0.882.613.3501 (17)142
N3—H73···Br1iii0.882.453.1956 (18)143
O2—H2···Br10.842.413.2378 (17)168
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x−1, y+1, z; (iii) x, y+1, z.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i0.841.822.657 (2)175
N1—H71···Br1ii0.882.613.3501 (17)142
N3—H73···Br1iii0.882.453.1956 (18)143
O2—H2···Br10.842.413.2378 (17)168
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x−1, y+1, z; (iii) x, y+1, z.
Acknowledgements top

The authors thank Professor P. Klüfers for generous allocation of diffractometer time.

references
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