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ISSN: 2056-9890

Quinoline-2-carbo­nitrile–fumaric acid (1/0.5)

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: hkfun@usm.my

(Received 13 August 2010; accepted 14 August 2010; online 21 August 2010)

The asymmetric unit of the title compound, C10H6N2·0.5C4H4O4, consists of one quinoline-2-carbonitrile mol­ecule and a half-mol­ecule of fumaric acid, which lies on an inversion center. The quinoline-2-carbonitrile mol­ecule is almost planar, with an r.m.s. deviation of 0.008 (1) Å. The acid and base are linked together via pairs of inter­molecular C—H⋯O and O—H⋯N hydrogen bonds, forming R22(8) ring motifs. In the crystal, the carbonitrile mol­ecules are further linked by inter­molecular C—H⋯N hydrogen bonds, generating R22(10) ring motifs, resulting in zigzag chains running along the c axis.

Related literature

For the biological activity and syntheses of quinoline derivatives, see: Sasaki et al. (1998[Sasaki, K., Tsurumori, A. & Hirota, T. (1998). J. Chem. Soc. Perkin Trans. 1, pp. 3851-3856.]); Reux et al. (2009[Reux, B., Nevalainen, T., Raitio, K. H. & Koskinen, A. M. P. (2009). Bioorg. Med. Chem. 17, 4441-4447.]). For related structures, see: Loh, Fun et al. (2010[Loh, W.-S., Fun, H.-K., Kiran, K., Sarveswari, S. & Vijayakumar, V. (2010). Acta Cryst. E66, o1237.]); Loh, Quah et al. (2010[Loh, W.-S., Quah, C. K., Hemamalini, M. & Fun, H.-K. (2010). Acta Cryst. E66, o2396.]); Quah et al. (2010[Quah, C. K., Loh, W.-S., Hemamalini, M. & Fun, H.-K. (2010). Acta Cryst. E66, o2254.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]). For reference bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C10H6N2·0.5C4H4O4

  • Mr = 212.20

  • Monoclinic, P 21 /c

  • a = 3.7239 (1) Å

  • b = 19.1958 (3) Å

  • c = 13.6454 (2) Å

  • β = 93.805 (1)°

  • V = 973.27 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 100 K

  • 0.17 × 0.15 × 0.09 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.983, Tmax = 0.991

  • 10682 measured reflections

  • 2566 independent reflections

  • 1983 reflections with I > 2σ(I)

  • Rint = 0.032

Refinement
  • R[F2 > 2σ(F2)] = 0.047

  • wR(F2) = 0.128

  • S = 1.06

  • 2566 reflections

  • 149 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.37 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H1O2⋯N1 0.92 (2) 1.83 (2) 2.7272 (16) 167 (2)
C2—H2A⋯O1 0.93 2.44 3.3300 (19) 161
C8—H8A⋯N2i 0.93 2.60 3.467 (2) 156
Symmetry code: (i) -x+2, -y+1, -z.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Heterocyclic molecules containing the cyano group are useful as drug intermediates. Syntheses of quinoline derivatives have been discussed earlier (Sasaki et al., 1998; Reux et al., 2009). In continuation of our previous work, we have synthesized a number of quinoline compounds to investigate the hydrogen bonding patterns in these compounds (Loh, Fun et al., 2010; Loh, Quah et al., 2010; Quah et al., 2010). Here we report the synthesis of quinoline-2-carbonitrile fumaric acid.

The asymmetric unit of the title compound (Fig. 1) consists of one quinoline-2-carbonitrile molecule and a half-molecule of fumaric acid. The fumaric acid (C11/C12/O1/O2/C11A/C12A/O1A/O2A) lies on the inversion center generated by the symmetry code -x, -y + 1, -z + 1. The quinoline-2-carbonitrile (C1–C10/N1/N2) is almost planar, with an r.m.s. deviation of 0.008 (1) Å. The acid and base are linked together via pairs of intermolecular C2—H2A···O1 and O2—H1O2···N1 hydrogen bonds (Table 1), forming R22(8) ring motifs (Bernstein et al., 1995). The bond lengths (Allen et al., 1987) and angles in the title compound are within normal ranges and comparable to those in the structure of quinoline-2-carbonitrile (Loh, Quah et al., 2010).

In the crystal packing (Fig. 2), the carbonitrile molecules are further linked by intermolecular C8—H8A···N2 hydrogen bonds (Table 1), generating R22(10) ring motifs (Bernstein et al., 1995), and resulting in zigzag chains running along the c axis.

Related literature top

For the biological activity and syntheses of quinoline derivatives, see: Sasaki et al. (1998); Reux et al. (2009). For related structures, see: Loh, Fun et al. (2010); Loh, Quah et al. (2010); Quah et al. (2010). For hydrogen-bond motifs, see: Bernstein et al. (1995). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986). For reference bond-length data, see: Allen et al. (1987).

Experimental top

A hot methanol solution (20 ml) of quinoline-2-carbonitrile (39 mg, Aldrich) and fumaric acid (29 mg, Aldrich) were mixed and warmed over a magnetic stirrer hotplate for a few minutes. The resulting solution was allowed to cool slowly to room temperature. Colourless crystals suitable for X-ray diffraction appeared after a few days.

Refinement top

H1O2 was located from a difference Fourier map and refined freely (O—H = 0.92 (2) Å). The remaining H atoms were positioned geometrically with C—H = 0.93 Å and were refined using a riding model, with Uiso(H) = 1.2 Ueq(C).

Structure description top

Heterocyclic molecules containing the cyano group are useful as drug intermediates. Syntheses of quinoline derivatives have been discussed earlier (Sasaki et al., 1998; Reux et al., 2009). In continuation of our previous work, we have synthesized a number of quinoline compounds to investigate the hydrogen bonding patterns in these compounds (Loh, Fun et al., 2010; Loh, Quah et al., 2010; Quah et al., 2010). Here we report the synthesis of quinoline-2-carbonitrile fumaric acid.

The asymmetric unit of the title compound (Fig. 1) consists of one quinoline-2-carbonitrile molecule and a half-molecule of fumaric acid. The fumaric acid (C11/C12/O1/O2/C11A/C12A/O1A/O2A) lies on the inversion center generated by the symmetry code -x, -y + 1, -z + 1. The quinoline-2-carbonitrile (C1–C10/N1/N2) is almost planar, with an r.m.s. deviation of 0.008 (1) Å. The acid and base are linked together via pairs of intermolecular C2—H2A···O1 and O2—H1O2···N1 hydrogen bonds (Table 1), forming R22(8) ring motifs (Bernstein et al., 1995). The bond lengths (Allen et al., 1987) and angles in the title compound are within normal ranges and comparable to those in the structure of quinoline-2-carbonitrile (Loh, Quah et al., 2010).

In the crystal packing (Fig. 2), the carbonitrile molecules are further linked by intermolecular C8—H8A···N2 hydrogen bonds (Table 1), generating R22(10) ring motifs (Bernstein et al., 1995), and resulting in zigzag chains running along the c axis.

For the biological activity and syntheses of quinoline derivatives, see: Sasaki et al. (1998); Reux et al. (2009). For related structures, see: Loh, Fun et al. (2010); Loh, Quah et al. (2010); Quah et al. (2010). For hydrogen-bond motifs, see: Bernstein et al. (1995). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986). For reference bond-length data, see: Allen et al. (1987).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound showing 50% probability displacement ellipsoids for non-H atoms and the atom-numbering scheme. Atoms with suffix A were generated by the symmetry code -x, -y + 1, -z + 1. Hydrogen atoms are shown as spheres of arbitrary radius.
[Figure 2] Fig. 2. The crystal structure of the title compound, viewed along the a axis, showing the zigzag chains running along the c axis. Dashed lines indicate hydrogen bonds. H atoms not involved in the hydrogen bond interactions have been omitted for clarity.
Quinoline-2-carbonitrile–fumaric acid (1/0.5) top
Crystal data top
C10H6N2·0.5C4H4O4F(000) = 440
Mr = 212.20Dx = 1.448 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3503 reflections
a = 3.7239 (1) Åθ = 2.6–30.1°
b = 19.1958 (3) ŵ = 0.10 mm1
c = 13.6454 (2) ÅT = 100 K
β = 93.805 (1)°Block, colourless
V = 973.27 (3) Å30.17 × 0.15 × 0.09 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
2566 independent reflections
Radiation source: fine-focus sealed tube1983 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.032
φ and ω scansθmax = 29.0°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 55
Tmin = 0.983, Tmax = 0.991k = 2621
10682 measured reflectionsl = 1818
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)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.128H atoms treated by a mixture of independent and constrained refinement
S = 1.06 w = 1/[σ2(Fo2) + (0.0637P)2 + 0.2928P]
where P = (Fo2 + 2Fc2)/3
2566 reflections(Δ/σ)max < 0.001
149 parametersΔρmax = 0.37 e Å3
0 restraintsΔρmin = 0.26 e Å3
Crystal data top
C10H6N2·0.5C4H4O4V = 973.27 (3) Å3
Mr = 212.20Z = 4
Monoclinic, P21/cMo Kα radiation
a = 3.7239 (1) ŵ = 0.10 mm1
b = 19.1958 (3) ÅT = 100 K
c = 13.6454 (2) Å0.17 × 0.15 × 0.09 mm
β = 93.805 (1)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
2566 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
1983 reflections with I > 2σ(I)
Tmin = 0.983, Tmax = 0.991Rint = 0.032
10682 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0470 restraints
wR(F2) = 0.128H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.37 e Å3
2566 reflectionsΔρmin = 0.26 e Å3
149 parameters
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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
O10.1218 (3)0.38047 (6)0.42628 (8)0.0239 (3)
O20.3112 (3)0.45849 (6)0.31757 (7)0.0191 (3)
C110.0375 (4)0.50196 (8)0.45325 (10)0.0161 (3)
H11A0.01410.54450.42090.019*
C120.1585 (4)0.43988 (8)0.39883 (10)0.0153 (3)
H1O20.393 (6)0.4215 (12)0.2830 (15)0.042 (6)*
C70.7889 (4)0.28524 (8)0.03215 (10)0.0168 (3)
H7A0.85930.25960.02110.020*
C80.8084 (4)0.35628 (8)0.03082 (10)0.0170 (3)
H8A0.89020.37980.02290.020*
C90.7002 (4)0.39284 (8)0.11370 (10)0.0155 (3)
C100.7209 (4)0.46837 (8)0.11449 (10)0.0179 (3)
N10.5786 (3)0.36333 (6)0.19310 (8)0.0146 (3)
N20.7411 (4)0.52815 (7)0.11298 (10)0.0252 (3)
C10.5589 (4)0.29220 (8)0.19492 (10)0.0148 (3)
C20.4324 (4)0.25919 (8)0.27928 (10)0.0162 (3)
H2A0.36410.28570.33190.019*
C30.4121 (4)0.18825 (8)0.28244 (11)0.0179 (3)
H3A0.33080.16680.33790.021*
C40.5123 (4)0.14668 (8)0.20288 (11)0.0191 (3)
H4A0.49700.09840.20670.023*
C50.6316 (4)0.17730 (8)0.12047 (11)0.0183 (3)
H5A0.69330.14980.06800.022*
C60.6612 (4)0.25059 (8)0.11479 (10)0.0155 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0376 (7)0.0139 (6)0.0214 (5)0.0008 (5)0.0117 (5)0.0000 (4)
O20.0273 (6)0.0154 (6)0.0155 (5)0.0003 (5)0.0075 (4)0.0023 (4)
C110.0202 (7)0.0116 (7)0.0168 (7)0.0001 (6)0.0033 (6)0.0014 (5)
C120.0171 (7)0.0159 (7)0.0130 (6)0.0005 (6)0.0013 (5)0.0005 (5)
C70.0169 (7)0.0205 (8)0.0130 (6)0.0027 (6)0.0013 (5)0.0023 (5)
C80.0173 (7)0.0201 (8)0.0139 (6)0.0006 (6)0.0032 (5)0.0012 (5)
C90.0159 (7)0.0156 (8)0.0149 (6)0.0004 (6)0.0010 (5)0.0010 (5)
C100.0193 (7)0.0200 (8)0.0145 (6)0.0002 (6)0.0029 (5)0.0015 (6)
N10.0172 (6)0.0128 (6)0.0139 (6)0.0006 (5)0.0016 (5)0.0005 (5)
N20.0335 (8)0.0183 (7)0.0245 (7)0.0010 (6)0.0062 (6)0.0020 (6)
C10.0167 (7)0.0143 (7)0.0136 (6)0.0010 (6)0.0017 (5)0.0002 (5)
C20.0195 (7)0.0165 (8)0.0129 (6)0.0008 (6)0.0024 (5)0.0004 (5)
C30.0198 (7)0.0173 (8)0.0166 (7)0.0007 (6)0.0017 (6)0.0024 (6)
C40.0221 (8)0.0126 (7)0.0223 (7)0.0003 (6)0.0002 (6)0.0005 (6)
C50.0219 (7)0.0162 (8)0.0170 (7)0.0017 (6)0.0017 (6)0.0043 (6)
C60.0159 (7)0.0163 (8)0.0142 (6)0.0010 (6)0.0010 (5)0.0015 (5)
Geometric parameters (Å, º) top
O1—C121.2108 (18)C10—N21.150 (2)
O2—C121.3281 (16)N1—C11.3676 (19)
O2—H1O20.92 (2)C1—C21.4214 (19)
C11—C11i1.326 (3)C1—C61.4262 (19)
C11—C121.489 (2)C2—C31.365 (2)
C11—H11A0.9300C2—H2A0.9300
C7—C81.366 (2)C3—C41.417 (2)
C7—C61.4181 (19)C3—H3A0.9300
C7—H7A0.9300C4—C51.369 (2)
C8—C91.4121 (19)C4—H4A0.9300
C8—H8A0.9300C5—C61.414 (2)
C9—N11.3287 (17)C5—H5A0.9300
C9—C101.452 (2)
C12—O2—H1O2113.4 (14)N1—C1—C2118.74 (12)
C11i—C11—C12121.62 (18)N1—C1—C6121.86 (12)
C11i—C11—H11A119.2C2—C1—C6119.40 (13)
C12—C11—H11A119.2C3—C2—C1119.51 (13)
O1—C12—O2125.09 (13)C3—C2—H2A120.2
O1—C12—C11123.72 (13)C1—C2—H2A120.2
O2—C12—C11111.19 (12)C2—C3—C4121.31 (13)
C8—C7—C6119.98 (13)C2—C3—H3A119.3
C8—C7—H7A120.0C4—C3—H3A119.3
C6—C7—H7A120.0C5—C4—C3120.25 (14)
C7—C8—C9117.87 (13)C5—C4—H4A119.9
C7—C8—H8A121.1C3—C4—H4A119.9
C9—C8—H8A121.1C4—C5—C6120.21 (13)
N1—C9—C8124.88 (14)C4—C5—H5A119.9
N1—C9—C10116.13 (12)C6—C5—H5A119.9
C8—C9—C10118.98 (12)C5—C6—C7122.80 (13)
N2—C10—C9178.33 (15)C5—C6—C1119.31 (12)
C9—N1—C1117.52 (12)C7—C6—C1117.89 (13)
C11i—C11—C12—O117.0 (3)C1—C2—C3—C40.4 (2)
C11i—C11—C12—O2162.72 (18)C2—C3—C4—C50.2 (2)
C6—C7—C8—C90.3 (2)C3—C4—C5—C61.0 (2)
C7—C8—C9—N10.4 (2)C4—C5—C6—C7178.87 (14)
C7—C8—C9—C10179.54 (14)C4—C5—C6—C11.2 (2)
C8—C9—N1—C10.5 (2)C8—C7—C6—C5179.47 (14)
C10—C9—N1—C1179.45 (13)C8—C7—C6—C10.4 (2)
C9—N1—C1—C2179.50 (13)N1—C1—C6—C5179.37 (14)
C9—N1—C1—C60.5 (2)C2—C1—C6—C50.6 (2)
N1—C1—C2—C3179.81 (14)N1—C1—C6—C70.5 (2)
C6—C1—C2—C30.2 (2)C2—C1—C6—C7179.50 (13)
Symmetry code: (i) x, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H1O2···N10.92 (2)1.83 (2)2.7272 (16)167 (2)
C2—H2A···O10.932.443.3300 (19)161
C8—H8A···N2ii0.932.603.467 (2)156
Symmetry code: (ii) x+2, y+1, z.

Experimental details

Crystal data
Chemical formulaC10H6N2·0.5C4H4O4
Mr212.20
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)3.7239 (1), 19.1958 (3), 13.6454 (2)
β (°) 93.805 (1)
V3)973.27 (3)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.17 × 0.15 × 0.09
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.983, 0.991
No. of measured, independent and
observed [I > 2σ(I)] reflections
10682, 2566, 1983
Rint0.032
(sin θ/λ)max1)0.682
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.128, 1.06
No. of reflections2566
No. of parameters149
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.37, 0.26

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H1O2···N10.92 (2)1.83 (2)2.7272 (16)167 (2)
C2—H2A···O10.93002.44003.3300 (19)161.00
C8—H8A···N2i0.93002.60003.467 (2)156.00
Symmetry code: (i) x+2, y+1, z.
 

Footnotes

Thomson Reuters ResearcherID: C-7581-2009.

§Thomson Reuters ResearcherID: A-5525-2009.

Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

The authors thank Universiti Sains Malaysia (USM) for the Research University Golden Goose Grant (1001/PFIZIK/811012). WSL and CKQ thank USM for the award of USM fellowships and MH thanks USM for the award of a post-doctoral fellowship.

References

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