organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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4-Bromo-β-(2-oxoquinolin-4-yl­­oxy)cinnamo­nitrile: a three-dimensional framework structure built from N—H⋯O and C—H⋯O hydrogen bonds, and bromo–carbonyl and aromatic ππ stacking inter­actions

CROSSMARK_Color_square_no_text.svg

aDepartamento de Química, Universidad de Nariño, Ciudad Universitaria, Torobajo, AA 1175, Pasto, Colombia, bDepartamento de Química Inorgánica y Orgánica, Universidad de Jaén, 23071 Jaén, Spain, cDepartment of Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen AB24 3UE, Scotland, and dSchool of Chemistry, University of St Andrews, Fife KY16 9ST, Scotland
*Correspondence e-mail: cg@st-andrews.ac.uk

(Received 19 June 2006; accepted 19 June 2006; online 28 June 2006)

In the title compound, C18H11BrN2O2, the mol­ecules are linked into sheets by a combination of one N—H⋯O and two C—H⋯O hydrogen bonds, and the sheets are linked by an aromatic ππ stacking inter­action.

Comment

The title compound, (I)[link], has been prepared from 2,4-dihydroxy­quinoline and 4-bromo-β-chloro­cinnamonitrile as a potential inter­mediate for the synthesis of fused quinoline derivatives.

[Scheme 1]

The mol­ecules of compound (I)[link] show a significant deviation from planarity, as shown by the key torsion angles (Table 1[link]). The biggest deviation from planarity is associated with the rotation of the two effectively planar components of the mol­ecule about the O4—C17 bond, which is probably driven by the repulsive inter­action between the cyano substituent and the H atom bonded to C3 (Fig. 1[link]). Consistent with this, the bond angle at O4 is abnormally large.

While the C—C distances within the brominated aryl ring span only a rather narrow range [1.383 (3) − 1.400 (3) Å with mean value 1.389 Å], the distances in the other carbocyclic ring show evidence of some bond fixation, with bonds C5—C6 and C7—C8 significantly shorter than the remainder.

The mol­ecules of compound (I)[link] are linked by paired N—H⋯O hydrogen bonds (Table 2[link]) into centrosymmetric R22(8) (Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]) dimers, and the reference mol­ecule was selected so that it forms part of a dimer centred at ([1\over2], [1\over2], [1\over2]) (Fig. 2[link]). Atoms C12 and C18 in the mol­ecule at (x, y, z) both act as hydrogen bond donors to atom O2 in the mol­ecule at ([3\over2] − x, −[{1\over 2}] + y, [3\over2] − z), in an R21(7) motif. Propagation by the space group of these inter­actions then links the dimer centred at (1/2, 1/2, 1/2) as donor to those centred at (1, 0, 1) and (0, 1, 0), and as acceptor from those centred at (0, 0, 0) and (1, 1, 1), thereby forming a (10[\overline{1}]) sheet built from R21(7), R22(8) and R66(36) rings (Fig. 3[link]).

The rings C4A/C5–C8/C8A in the mol­ecules at (x, y, z) and (2 − x, 1 − y, 1 − z) form parts of the R22(8) dimers centred at ([1\over2], [1\over2], [1\over2]) and ([3\over2], [1\over2], [1\over2]), respectively. These rings are strictly parallel with an inter­planar spacing of 3.439 (2) Å: the corresponding ring-centroid separation is 3.799 (2) and the ring offset is 1.614 (2) Å. The effect of this inter­action is to link the sheets along the [100] direction (Fig. 4[link]), so forming a continuous three-dimensional structure.

The Br atom at (x, y, z) makes a short contact with the amide atom O2 in the mol­ecule at (1 − x, −y, 1 − z), with Br⋯Oiii = 3.078 (2) Å and C—Br⋯Oiii = 164.3 (2)° [symmetry code: (iii) 1 − x, −y, 1 − z] and this weakly attractive bromo–carbonyl inter­action links the hydrogen-bonded dimers into a chain of edge-fused R22(8) and R22(22) rings (Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]; Starbuck et al., 1999[Starbuck, J., Norman, N. C. & Orpen, A. G. (1999). New J. Chem. 23, 969-972.]) along [010], further reinforcing the framework (Fig. 5[link]).

[Figure 1]
Figure 1
The molecular structure of (I)[link], showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2]
Figure 2
Part of the crystal structure of (I)[link], showing the formation of a hydrogen-bonded R22(8) dimer. Dashed lines indicate hydrogen bonds. For the sake of clarity, H atoms bonded to C atoms have been omitted. Atoms marked with an asterisk (*) are at the symmetry position (1 − x, 1 − y, 1 − z).
[Figure 3]
Figure 3
A stereoscopic view of part of the crystal structure of (I)[link], showing the formation of a hydrogen-bonded (10[\overline{1}]) sheet. Dashed lines indicate hydrogen bonds. For the sake of clarity, H atoms not involved in the motifs shown have been omitted.
[Figure 4]
Figure 4
A stereoscopic view of part of the crystal structure of (I)[link], showing the formation of a π-stacked chain of hydrogen-bonded dimers along [100], linking the (10[\overline{1}]) sheets. Dashed lines indicate hydrogen bonds. For the sake of clarity, H atoms bonded to C atoms have been omitted.
[Figure 5]
Figure 5
A stereoscopic view of part of the crystal structure of (I)[link], showing the formation of a [010] chain of edge-fused rings formed by hydrogen-bonded dimers linked by the Br⋯O contact. Dashed lines indicate hydrogen bonds and Br⋯O contacts. For the sake of clarity, H atoms bonded to C atoms have been omitted.

Experimental

A solution containing 4-bromo-β-chloro­cinnamonitrile (1 mmol), 2,4-dihydroxy­quinoline (1 mmol) and triethyl­amine (0.5 ml) in anhydrous ethanol (10 ml) was heated under reflux for 10 h. The resulting solid product was collected by filtration, washed with ethanol and recrystallized from ethanol to give pale-yellow crystals suitable for single-crystal X-ray diffraction (m.p. 582 K, yield 60%).

Crystal data
  • C18H11BrN2O2

  • Mr = 367.20

  • Monoclinic, P 21 /n

  • a = 8.9860 (2) Å

  • b = 12.4111 (3) Å

  • c = 13.6138 (3) Å

  • β = 92.006 (2)°

  • V = 1517.36 (6) Å3

  • Z = 4

  • Dx = 1.607 Mg m−3

  • Mo Kα radiation

  • μ = 2.72 mm−1

  • T = 120 (2) K

  • Block, pale yellow

  • 0.70 × 0.50 × 0.30 mm

Data collection
  • Bruker–Nonius KappaCCD diffractometer

  • φ and ω scans

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Version 2.10. University of Göttingen, Germany.]) Tmin = 0.224, Tmax = 0.441

  • 17684 measured reflections

  • 3463 independent reflections

  • 2907 reflections with I > 2σ(I)

  • Rint = 0.034

  • θmax = 27.5°

Refinement
  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.032

  • wR(F2) = 0.080

  • S = 1.16

  • 3463 reflections

  • 208 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.033P)2 + 1.024P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max = 0.001

  • Δρmax = 0.36 e Å−3

  • Δρmin = −0.68 e Å−3

Table 1
Selected geometric parameters (Å, °)

C4A—C5 1.404 (3)
C5—C6 1.372 (3)
C6—C7 1.403 (3)
C7—C8 1.375 (3)
C8—C8A 1.404 (3)
C8A—C4A 1.400 (3)
C4—O4—C17 119.34 (15)
C3—C4—O4—C17 26.0 (3)
C4—O4—C17—C18 −118.0 (2)
C4—O4—C17—C11 68.3 (2)
O4—C17—C11—C12 −176.79 (18)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O2i 0.88 1.96 2.814 (2) 164
C12—H12⋯O2ii 0.95 2.52 3.435 (2) 163
C18—H18⋯O2ii 0.95 2.44 3.389 (3) 178
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}].

All H atoms were located in difference maps and then treated as riding atoms with C—H = 0.95 Å and N—H = 0.88 Å, and with Uiso(H) = 1.2Ueq(C,N).

Data collection: COLLECT (Hooft, 1999[Hooft, R. W. W. (1999). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SIR2004 (Burla et al., 2005[Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De Caro, L., Giacovazzo, C., Polidori, G. & Spagna, R. (2005). J. Appl. Cryst. 38, 381-388.]); program(s) used to refine structure: OSCAIL (McArdle, 2003[McArdle, P. (2003). OSCAIL for Windows. Version 10. Crystallography Centre, Chemistry Department, NUI Galway, Ireland.]) and SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXL97. University of Göttingen, Germany.]); molecular graphics: PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999[Ferguson, G. (1999). PRPKAPPA. University of Guelph, Canada.]).

Supporting information


Computing details top

Data collection: COLLECT (Hooft, 1999); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: OSCAIL (McArdle, 2003) and SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999).

4-Bromo-β-(2-oxoquinolin-4-yloxy)cinnamonitrile top
Crystal data top
C18H11BrN2O2F(000) = 736
Mr = 367.20Dx = 1.607 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3463 reflections
a = 8.9860 (2) Åθ = 3.1–27.5°
b = 12.4111 (3) ŵ = 2.72 mm1
c = 13.6138 (3) ÅT = 120 K
β = 92.006 (2)°Block, colourless
V = 1517.36 (6) Å30.70 × 0.50 × 0.30 mm
Z = 4
Data collection top
Bruker–Nonius KappaCCD
diffractometer
3463 independent reflections
Radiation source: Bruker-Nonius FR591 rotating anode2907 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 3.1°
φ and ω scansh = 1111
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
k = 1615
Tmin = 0.224, Tmax = 0.441l = 1717
17684 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)] = 0.032Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.080H-atom parameters constrained
S = 1.16 w = 1/[σ2(Fo2) + (0.033P)2 + 1.024P]
where P = (Fo2 + 2Fc2)/3
3463 reflections(Δ/σ)max = 0.001
208 parametersΔρmax = 0.36 e Å3
0 restraintsΔρmin = 0.68 e Å3
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.69050 (18)0.45629 (14)0.48541 (12)0.0153 (3)
C20.6573 (2)0.40615 (16)0.57075 (14)0.0145 (4)
O20.53963 (15)0.42863 (12)0.61305 (10)0.0175 (3)
C30.7623 (2)0.32710 (16)0.60798 (15)0.0152 (4)
C40.8893 (2)0.30846 (16)0.56033 (14)0.0140 (4)
O40.99737 (15)0.23650 (12)0.59192 (10)0.0163 (3)
C4A0.9243 (2)0.36467 (16)0.47165 (15)0.0145 (4)
C51.0543 (2)0.34596 (17)0.42009 (15)0.0179 (4)
C61.0770 (2)0.40041 (18)0.33419 (16)0.0217 (5)
C70.9722 (2)0.47594 (18)0.29849 (15)0.0204 (4)
C80.8443 (2)0.49569 (17)0.34809 (15)0.0180 (4)
C8A0.8191 (2)0.43912 (16)0.43525 (14)0.0146 (4)
C110.8644 (2)0.06677 (16)0.60203 (15)0.0155 (4)
C120.8128 (2)0.02104 (17)0.65539 (15)0.0193 (4)
C130.7290 (3)0.10121 (18)0.60951 (16)0.0225 (5)
C140.6977 (2)0.09451 (18)0.50928 (17)0.0213 (5)
Br140.59176 (3)0.207817 (19)0.445430 (18)0.02971 (9)
C150.7466 (2)0.00827 (18)0.45473 (16)0.0212 (5)
C160.8295 (2)0.07214 (17)0.50110 (16)0.0192 (4)
C170.9581 (2)0.14977 (16)0.64989 (15)0.0155 (4)
C181.0206 (2)0.14423 (17)0.74090 (16)0.0195 (4)
C191.1128 (3)0.22890 (18)0.77929 (16)0.0235 (5)
H10.62560.50280.46050.018*
H30.74230.28800.66610.018*
H51.12640.29580.44460.021*
H61.16420.38690.29860.026*
H70.98980.51390.23940.025*
H80.77390.54700.32370.022*
H120.83540.02570.72390.023*
H130.69340.16030.64630.027*
H150.72360.00430.38620.025*
H160.86300.13170.46400.023*
H181.00300.08270.78040.023*
N41.1869 (3)0.29569 (16)0.81204 (16)0.0334 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0154 (8)0.0145 (8)0.0157 (8)0.0024 (7)0.0023 (7)0.0027 (7)
C20.0162 (9)0.0134 (9)0.0138 (10)0.0011 (8)0.0018 (7)0.0023 (8)
O20.0176 (7)0.0191 (7)0.0158 (7)0.0037 (6)0.0005 (6)0.0010 (6)
C30.0189 (10)0.0141 (9)0.0125 (10)0.0004 (8)0.0010 (8)0.0004 (8)
C40.0165 (10)0.0107 (9)0.0146 (10)0.0001 (7)0.0045 (8)0.0014 (7)
O40.0151 (7)0.0164 (7)0.0171 (7)0.0026 (6)0.0016 (6)0.0044 (6)
C4A0.0156 (10)0.0124 (9)0.0153 (10)0.0019 (8)0.0023 (8)0.0011 (8)
C50.0180 (10)0.0185 (10)0.0170 (10)0.0014 (8)0.0015 (8)0.0009 (8)
C60.0199 (10)0.0247 (11)0.0208 (11)0.0005 (9)0.0035 (8)0.0004 (9)
C70.0246 (11)0.0225 (11)0.0141 (10)0.0058 (9)0.0007 (8)0.0041 (8)
C80.0192 (10)0.0167 (10)0.0179 (10)0.0018 (8)0.0038 (8)0.0034 (8)
C8A0.0151 (9)0.0146 (9)0.0138 (10)0.0029 (8)0.0027 (7)0.0020 (8)
C110.0151 (9)0.0164 (10)0.0148 (10)0.0045 (8)0.0015 (8)0.0018 (8)
C120.0234 (10)0.0203 (11)0.0141 (10)0.0005 (9)0.0010 (8)0.0001 (8)
C130.0278 (11)0.0186 (11)0.0214 (11)0.0013 (9)0.0056 (9)0.0001 (9)
C140.0181 (10)0.0191 (11)0.0267 (12)0.0005 (8)0.0016 (8)0.0047 (9)
Br140.02947 (14)0.02552 (14)0.03352 (15)0.00713 (10)0.00755 (10)0.00544 (10)
C150.0231 (11)0.0231 (11)0.0170 (11)0.0021 (9)0.0057 (8)0.0016 (9)
C160.0212 (10)0.0171 (10)0.0191 (11)0.0020 (8)0.0031 (8)0.0031 (8)
C170.0168 (10)0.0139 (10)0.0159 (10)0.0045 (8)0.0008 (8)0.0020 (8)
C180.0238 (11)0.0156 (10)0.0187 (11)0.0000 (8)0.0039 (8)0.0014 (8)
C190.0321 (12)0.0218 (11)0.0162 (11)0.0031 (10)0.0071 (9)0.0023 (9)
N40.0487 (13)0.0248 (11)0.0256 (11)0.0043 (10)0.0136 (10)0.0017 (9)
Geometric parameters (Å, º) top
N1—C21.360 (3)C8A—C4A1.400 (3)
N1—C8A1.379 (3)C8—H80.95
N1—H10.88C11—C121.398 (3)
C2—O21.253 (2)C11—C161.400 (3)
C2—C31.441 (3)C11—C171.468 (3)
C3—C41.352 (3)C12—C131.383 (3)
C3—H30.95C12—H120.95
C4—O41.377 (2)C13—C141.386 (3)
C4—C4A1.439 (3)C13—H130.95
O4—C171.388 (2)C14—C151.383 (3)
C4A—C51.404 (3)C14—Br141.892 (2)
C5—C61.372 (3)C15—C161.384 (3)
C5—H50.95C15—H150.95
C6—C71.403 (3)C16—H160.95
C6—H60.95C17—C181.344 (3)
C7—C81.375 (3)C18—C191.426 (3)
C7—H70.95C18—H180.95
C8—C8A1.404 (3)C19—N41.144 (3)
C2—N1—C8A124.39 (17)N1—C8A—C4A119.59 (18)
C2—N1—H1117.8N1—C8A—C8120.28 (18)
C8A—N1—H1117.8C4A—C8A—C8120.13 (19)
O2—C2—N1120.30 (18)C12—C11—C16118.67 (19)
O2—C2—C3122.87 (19)C12—C11—C17120.80 (18)
N1—C2—C3116.83 (18)C16—C11—C17120.49 (19)
C4—C3—C2120.07 (19)C13—C12—C11120.76 (19)
C4—C3—H3120.0C13—C12—H12119.6
C2—C3—H3120.0C11—C12—H12119.6
C3—C4—O4123.99 (18)C12—C13—C14119.3 (2)
C3—C4—C4A122.18 (18)C12—C13—H13120.3
O4—C4—C4A113.83 (17)C14—C13—H13120.3
C4—O4—C17119.34 (15)C15—C14—C13121.2 (2)
C8A—C4A—C5119.73 (19)C15—C14—Br14119.51 (16)
C8A—C4A—C4116.89 (18)C13—C14—Br14119.29 (17)
C5—C4A—C4123.35 (18)C14—C15—C16119.3 (2)
C6—C5—C4A119.72 (19)C14—C15—H15120.4
C6—C5—H5120.1C16—C15—H15120.4
C4A—C5—H5120.1C15—C16—C11120.8 (2)
C5—C6—C7120.4 (2)C15—C16—H16119.6
C5—C6—H6119.8C11—C16—H16119.6
C7—C6—H6119.8C18—C17—O4117.23 (18)
C8—C7—C6120.7 (2)C18—C17—C11125.99 (19)
C8—C7—H7119.6O4—C17—C11116.43 (17)
C6—C7—H7119.6C17—C18—C19121.3 (2)
C7—C8—C8A119.24 (19)C17—C18—H18119.4
C7—C8—H8120.4C19—C18—H18119.4
C8A—C8—H8120.4N4—C19—C18178.5 (2)
C8A—N1—C2—O2178.04 (18)C4—C4A—C8A—C8178.90 (18)
C8A—N1—C2—C32.5 (3)C7—C8—C8A—N1178.94 (18)
O2—C2—C3—C4178.26 (18)C7—C8—C8A—C4A0.9 (3)
N1—C2—C3—C42.3 (3)C16—C11—C12—C130.1 (3)
C2—C3—C4—O4178.32 (17)C17—C11—C12—C13177.63 (19)
C2—C3—C4—C4A0.6 (3)C11—C12—C13—C140.7 (3)
C3—C4—O4—C1726.0 (3)C12—C13—C14—C151.0 (3)
C4A—C4—O4—C17155.03 (17)C12—C13—C14—Br14176.84 (16)
C3—C4—C4A—C8A1.1 (3)C13—C14—C15—C160.6 (3)
O4—C4—C4A—C8A179.95 (16)Br14—C14—C15—C16177.29 (16)
C3—C4—C4A—C5179.20 (19)C14—C15—C16—C110.2 (3)
O4—C4—C4A—C51.8 (3)C12—C11—C16—C150.6 (3)
C8A—C4A—C5—C60.3 (3)C17—C11—C16—C15177.18 (19)
C4—C4A—C5—C6177.78 (19)C4—O4—C17—C18118.0 (2)
C4A—C5—C6—C71.1 (3)C4—O4—C17—C1168.3 (2)
C5—C6—C7—C80.9 (3)C12—C11—C17—C1810.1 (3)
C6—C7—C8—C8A0.1 (3)C16—C11—C17—C18167.6 (2)
C2—N1—C8A—C4A0.9 (3)O4—C17—C11—C12176.79 (18)
C2—N1—C8A—C8179.29 (18)C16—C11—C17—O45.5 (3)
C5—C4A—C8A—N1179.16 (18)O4—C17—C18—C195.5 (3)
C4—C4A—C8A—N10.9 (3)C11—C17—C18—C19178.5 (2)
C5—C4A—C8A—C80.7 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.881.962.814 (2)164
C12—H12···O2ii0.952.523.435 (2)163
C18—H18···O2ii0.952.443.389 (3)178
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+3/2, y1/2, z+3/2.
 

Acknowledgements

X-ray data were collected at the EPSRC X-ray Crystallographic Service, University of Southampton, England. JC and JT thanks the Consejería de Innovación, Ciencia y Empresa (Junta de Andalucía, Spain) and the Universidad de Jaén for financial support. JT also thanks the Universidad de Jaén for a research scholarship supporting a short stay at the EPSRC X-ray Crystallographic Service, University of Southampton, England. SC thanks UDENAR (Universidad de Narinõ, Colombia) for financial support.

References

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