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Acta Crystallogr Sect E Struct Rep Online. 2011 February 1; 67(Pt 2): o407–o408.
Published online 2011 January 15. doi:  10.1107/S1600536811001577
PMCID: PMC3051724

4-Chloro­benzaldehyde (1-isobutyl-1H-imidazo[4,5-c]quinolin-4-yl)hydrazone monohydrate

Abstract

In the title compound, C21H20ClN5·H2O, the 1H-imidazo[4,5-c]quinoline ring is approximately planar, with a maximum deviation of 0.0795 (7) Å, and it forms a dihedral angle of 7.65 (3)° with the chloro­phenyl ring. In the crystal, the components are linked into chains along the a axis via inter­molecular N—H(...)O, O—H(...)N and C—H(...)O hydrogen bonds. One of the H atoms of the water mol­ecule is disordered over two positions with a site-occupancy ratio of 0.80 (4):0.20 (4).

Related literature

For background to quinolines and their microbial activity, see: El-Subbagh et al. (2000 [triangle]); Atwell et al. (1989 [triangle]); Kuo et al. (1993 [triangle]); Xia et al. (1998 [triangle]). For the biological activity of Schiff base hydrazones, see: Colins & Lyne (1970 [triangle]); Ochiai (1977 [triangle]). For bond-length data, see: Allen et al. (1987 [triangle]). For related structures, see: Loh et al. (2011a [triangle],b [triangle]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 [triangle]).

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Object name is e-67-0o407-scheme1.jpg

Experimental

Crystal data

  • C21H20ClN5·H2O
  • M r = 395.89
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-67-0o407-efi1.jpg
  • a = 10.4117 (3) Å
  • b = 18.2365 (6) Å
  • c = 11.9019 (3) Å
  • β = 117.809 (2)°
  • V = 1998.85 (10) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.21 mm−1
  • T = 100 K
  • 0.49 × 0.45 × 0.18 mm

Data collection

  • Bruker SMART APEXII DUO CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2009 [triangle]) T min = 0.904, T max = 0.963
  • 39468 measured reflections
  • 10411 independent reflections
  • 8351 reflections with I > 2σ(I)
  • R int = 0.032

Refinement

  • R[F 2 > 2σ(F 2)] = 0.045
  • wR(F 2) = 0.135
  • S = 1.04
  • 10411 reflections
  • 260 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 1.19 e Å−3
  • Δρmin = −0.47 e Å−3

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

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811001577/is2658sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811001577/is2658Isup2.hkl

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

Acknowledgments

HKF and WSL thank Universiti Sains Malaysia (USM) for the Research University Grant (1001/PFIZIK/811160). WSL also thanks the Malaysian Government and USM for the award of a Research Fellowship.

supplementary crystallographic information

Comment

Quinolines and their derivatives are important constituents of pharmacologically active synthetic compounds as these systems have been associated with a wide spectrum of biological properties (El-Subbagh et al., 2000) such as DNA binding capability (Atwell et al., 1989) and antitumor activities (Kuo et al., 1993; Xia et al., 1998). The study of Schiff base hydrazones has been growing because of their antimicrobial, anti-tuberculosis and anti-tumour activities (Colins & Lyne, 1970; Ochiai, 1977).

The asymmetric unit of the title compound, (Fig. 1), consists of one 4-chlorobenzaldehyde(1-isobutyl-1H-imidazo[4,5-c]quinolin-4-yl) hydrazone molecule and one water molecule. One of the H atoms attached to the water molecule is disordered over two positions with the site occupancy ratio of 0.80 (4):0.20 (4). The 1H-imidazo[4,5-c]quinoline ring (C1–C6/N1/C7/C8/N3/C10/N2/C9) is approximately planar with a maximum deviation of 0.0795 (7) Å at atom C2 and it forms a dihedral angle of 7.65 (3)° with the chlorophenyl ring (Cl1/C11–C16) with maximum deviation of 0.0286 (3) Å at atom Cl1. Bond lengths (Allen et al., 1987) and angles are within the normal ranges and are comparable to the related structures (Loh et al., 2011a,b).

In the crystal packing (Fig. 2), the molecules are linked into chains along the a axis by the water molecules via intermolecular N4—H1N4···O1W, O1W—H1W1···N1, C10—H10A···O1W and C18—H18B···O1W hydrogen bonds (Table 1).

Experimental

A mixture of 4-hydrazino-1-isobutyl-1H-imidazo[4,5-c]quinoline (2.5 g, 0.0098 mole) and 4-chlorobenzaldehyde (1.38 g, 0.0098 mole) in absolute ethanol was refluxed for 4 h in the presence of acetic acid (1 ml). The product, 4-chlorobenzaldehyde (1-isobutyl-1H-imidazo[4,5-c]quinolin-4-yl)hydrazone, was obtained after cooling and it was crystallized from absolute ethanol. Yield: 3.4 g (80%). Crystals suitable for X-ray analysis were obtained from ethanol by slow evaporation.

Refinement

O- and N-bound H atoms were located from a difference Fourier map. O-bound H atoms were then fixed at their found positions (O—H = 0.8330 to 0.8554 Å), with Uiso(H) = 1.5Ueq(O), whereas N-bound H atoms was refined freely [N—H = 0.875 (18) Å]. The remaining H atoms were positioned geometrically with the bond lengths of C—H = 0.93 to 0.98 Å and were refined using a riding model, with Uiso(H) = 1.2 or 1.5Ueq(C). A rotating group model was applied to the methyl groups. The heighest residual electron density peak is located 1.01 Å from atom O1W.

Figures

Fig. 1.
The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme. The open bond indicates the minor component.
Fig. 2.
The crystal packing of the title compound, showing the chains along the a axis. H atoms not involved in the intermolecular interactions (dashed lines) have been omitted for clarity. Only major component is shown.

Crystal data

C21H20ClN5·H2OF(000) = 832
Mr = 395.89Dx = 1.316 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 9978 reflections
a = 10.4117 (3) Åθ = 4.0–37.5°
b = 18.2365 (6) ŵ = 0.21 mm1
c = 11.9019 (3) ÅT = 100 K
β = 117.809 (2)°Plate, yellow
V = 1998.85 (10) Å30.49 × 0.45 × 0.18 mm
Z = 4

Data collection

Bruker SMART APEXII DUO CCD area-detector diffractometer10411 independent reflections
Radiation source: fine-focus sealed tube8351 reflections with I > 2σ(I)
graphiteRint = 0.032
[var phi] and ω scansθmax = 37.6°, θmin = 4.0°
Absorption correction: multi-scan (SADABS; Bruker, 2009)h = −17→17
Tmin = 0.904, Tmax = 0.963k = −31→30
39468 measured reflectionsl = −20→20

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.135H atoms treated by a mixture of independent and constrained refinement
S = 1.04w = 1/[σ2(Fo2) + (0.0715P)2 + 0.4845P] where P = (Fo2 + 2Fc2)/3
10411 reflections(Δ/σ)max = 0.001
260 parametersΔρmax = 1.19 e Å3
0 restraintsΔρmin = −0.47 e Å3

Special details

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)

xyzUiso*/UeqOcc. (<1)
Cl1−0.37283 (3)−0.053039 (16)0.46655 (3)0.03357 (7)
N10.00417 (7)0.13498 (4)0.01185 (6)0.01373 (11)
N20.33923 (7)0.14996 (4)−0.08204 (7)0.01514 (11)
N30.35384 (7)0.06015 (4)0.05254 (7)0.01630 (12)
N40.13161 (8)0.03567 (4)0.13737 (7)0.01564 (11)
N50.02778 (7)0.02713 (4)0.17545 (6)0.01482 (11)
C10.09304 (8)0.20371 (4)−0.11917 (7)0.01242 (11)
C20.06369 (8)0.25958 (4)−0.21028 (7)0.01464 (12)
H2A0.12600.2664−0.24550.018*
C3−0.05646 (8)0.30406 (4)−0.24743 (7)0.01589 (12)
H3A−0.07490.3407−0.30750.019*
C4−0.15108 (8)0.29408 (4)−0.19448 (8)0.01637 (13)
H4A−0.22970.3255−0.21710.020*
C5−0.12834 (8)0.23813 (4)−0.10935 (8)0.01560 (12)
H5A−0.19320.2314−0.07680.019*
C6−0.00740 (8)0.19089 (4)−0.07104 (7)0.01287 (11)
C70.11700 (8)0.09093 (4)0.05390 (7)0.01293 (11)
C80.22740 (8)0.09992 (4)0.01609 (7)0.01314 (11)
C90.21572 (8)0.15557 (4)−0.06761 (7)0.01280 (11)
C100.41677 (9)0.09246 (4)−0.00837 (8)0.01736 (13)
H10A0.50540.0774−0.00170.021*
C110.04705 (9)−0.02385 (4)0.25628 (7)0.01614 (13)
H11A0.1279−0.05430.28500.019*
C12−0.05978 (9)−0.03357 (4)0.30283 (7)0.01541 (12)
C13−0.18721 (9)0.00855 (4)0.25432 (7)0.01694 (13)
H13A−0.20670.04150.18870.020*
C14−0.28457 (10)0.00168 (5)0.30303 (8)0.01947 (14)
H14A−0.36900.02960.27040.023*
C15−0.25383 (10)−0.04775 (5)0.40152 (8)0.02080 (15)
C16−0.13059 (11)−0.09132 (5)0.44958 (8)0.02182 (15)
H16A−0.1126−0.12480.51420.026*
C17−0.03391 (10)−0.08415 (5)0.39943 (8)0.01941 (14)
H17A0.0488−0.11340.43060.023*
C180.38977 (9)0.19795 (4)−0.15243 (8)0.01655 (13)
H18A0.31240.2040−0.23850.020*
H18B0.47110.1749−0.15700.020*
C190.43656 (8)0.27358 (4)−0.09030 (8)0.01657 (13)
H19A0.35460.2959−0.08390.020*
C200.56378 (11)0.26719 (6)0.04269 (9)0.02498 (17)
H20A0.59320.31530.07840.037*
H20B0.64350.24330.03830.037*
H20C0.53490.23900.09520.037*
C210.47505 (11)0.32187 (6)−0.17470 (10)0.02624 (18)
H21A0.50080.3700−0.13820.039*
H21B0.39290.3253−0.25760.039*
H21C0.55560.3008−0.18150.039*
H1N40.2039 (19)0.0049 (9)0.1601 (16)0.035 (4)*
O1W0.70320 (9)0.09494 (4)0.93489 (12)0.0421 (3)
H1W10.79120.10250.95950.063*
H2WA0.66330.07640.86030.063*0.80 (4)
H2WB0.69150.04920.94050.063*0.20 (4)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cl10.03921 (14)0.03795 (14)0.03987 (14)−0.00160 (10)0.03211 (12)0.00615 (10)
N10.0138 (2)0.0145 (2)0.0160 (2)0.00128 (19)0.0096 (2)0.0020 (2)
N20.0138 (2)0.0149 (3)0.0216 (3)0.0012 (2)0.0124 (2)0.0016 (2)
N30.0137 (3)0.0151 (3)0.0227 (3)0.0020 (2)0.0107 (2)0.0021 (2)
N40.0154 (3)0.0166 (3)0.0188 (3)0.0029 (2)0.0112 (2)0.0044 (2)
N50.0165 (3)0.0153 (3)0.0161 (3)−0.0005 (2)0.0104 (2)0.0009 (2)
C10.0114 (3)0.0139 (3)0.0136 (3)0.0000 (2)0.0072 (2)0.0001 (2)
C20.0139 (3)0.0168 (3)0.0152 (3)0.0000 (2)0.0085 (2)0.0017 (2)
C30.0142 (3)0.0177 (3)0.0162 (3)0.0010 (2)0.0074 (2)0.0034 (2)
C40.0134 (3)0.0168 (3)0.0196 (3)0.0019 (2)0.0083 (2)0.0032 (2)
C50.0134 (3)0.0169 (3)0.0197 (3)0.0020 (2)0.0103 (2)0.0029 (2)
C60.0122 (3)0.0142 (3)0.0147 (3)0.0002 (2)0.0084 (2)0.0004 (2)
C70.0132 (3)0.0136 (3)0.0141 (3)−0.0003 (2)0.0081 (2)−0.0001 (2)
C80.0121 (3)0.0132 (3)0.0163 (3)0.0004 (2)0.0084 (2)0.0003 (2)
C90.0120 (3)0.0138 (3)0.0154 (3)−0.0003 (2)0.0087 (2)−0.0003 (2)
C100.0149 (3)0.0157 (3)0.0258 (3)0.0025 (2)0.0132 (3)0.0025 (3)
C110.0175 (3)0.0161 (3)0.0162 (3)0.0004 (2)0.0090 (2)0.0025 (2)
C120.0187 (3)0.0150 (3)0.0142 (3)−0.0020 (2)0.0091 (2)0.0007 (2)
C130.0193 (3)0.0173 (3)0.0167 (3)−0.0005 (2)0.0105 (3)0.0020 (2)
C140.0211 (3)0.0198 (3)0.0218 (3)−0.0012 (3)0.0136 (3)0.0011 (3)
C150.0261 (4)0.0216 (3)0.0209 (3)−0.0049 (3)0.0162 (3)−0.0001 (3)
C160.0277 (4)0.0224 (4)0.0189 (3)−0.0022 (3)0.0138 (3)0.0045 (3)
C170.0228 (4)0.0192 (3)0.0175 (3)0.0001 (3)0.0104 (3)0.0043 (3)
C180.0162 (3)0.0188 (3)0.0200 (3)0.0003 (2)0.0130 (3)0.0017 (2)
C190.0139 (3)0.0177 (3)0.0198 (3)0.0002 (2)0.0094 (3)0.0031 (2)
C200.0216 (4)0.0287 (4)0.0210 (4)−0.0013 (3)0.0070 (3)0.0022 (3)
C210.0255 (4)0.0260 (4)0.0297 (4)−0.0023 (3)0.0150 (4)0.0094 (3)
O1W0.0217 (3)0.0222 (3)0.0865 (8)0.0064 (3)0.0287 (4)0.0188 (4)

Geometric parameters (Å, °)

Cl1—C151.7430 (9)C11—H11A0.9300
N1—C71.3143 (10)C12—C171.3985 (11)
N1—C61.3842 (9)C12—C131.4032 (12)
N2—C101.3638 (10)C13—C141.3884 (11)
N2—C91.3782 (9)C13—H13A0.9300
N2—C181.4684 (10)C14—C151.3924 (12)
N3—C101.3210 (10)C14—H14A0.9300
N3—C81.3836 (10)C15—C161.3857 (14)
N4—N51.3622 (9)C16—C171.3955 (12)
N4—C71.3728 (10)C16—H16A0.9300
N4—H1N40.875 (18)C17—H17A0.9300
N5—C111.2845 (10)C18—C191.5330 (12)
C1—C21.4135 (10)C18—H18A0.9700
C1—C61.4267 (10)C18—H18B0.9700
C1—C91.4308 (10)C19—C201.5222 (12)
C2—C31.3793 (11)C19—C211.5233 (12)
C2—H2A0.9300C19—H19A0.9800
C3—C41.4072 (11)C20—H20A0.9600
C3—H3A0.9300C20—H20B0.9600
C4—C51.3783 (11)C20—H20C0.9600
C4—H4A0.9300C21—H21A0.9600
C5—C61.4142 (10)C21—H21B0.9600
C5—H5A0.9300C21—H21C0.9600
C7—C81.4259 (10)O1W—H1W10.8330
C8—C91.3872 (10)O1W—H2WA0.8554
C10—H10A0.9300O1W—H2WB0.8508
C11—C121.4665 (11)
C7—N1—C6119.13 (6)C17—C12—C11120.07 (7)
C10—N2—C9106.49 (6)C13—C12—C11121.10 (7)
C10—N2—C18124.26 (6)C14—C13—C12120.87 (7)
C9—N2—C18129.08 (6)C14—C13—H13A119.6
C10—N3—C8103.72 (6)C12—C13—H13A119.6
N5—N4—C7119.18 (6)C13—C14—C15118.96 (8)
N5—N4—H1N4121.7 (12)C13—C14—H14A120.5
C7—N4—H1N4119.0 (12)C15—C14—H14A120.5
C11—N5—N4117.46 (7)C16—C15—C14121.57 (8)
C2—C1—C6119.31 (6)C16—C15—Cl1119.88 (6)
C2—C1—C9126.97 (6)C14—C15—Cl1118.54 (7)
C6—C1—C9113.71 (6)C15—C16—C17118.91 (8)
C3—C2—C1120.60 (7)C15—C16—H16A120.5
C3—C2—H2A119.7C17—C16—H16A120.5
C1—C2—H2A119.7C16—C17—C12120.84 (8)
C2—C3—C4120.01 (7)C16—C17—H17A119.6
C2—C3—H3A120.0C12—C17—H17A119.6
C4—C3—H3A120.0N2—C18—C19112.26 (6)
C5—C4—C3120.59 (7)N2—C18—H18A109.2
C5—C4—H4A119.7C19—C18—H18A109.2
C3—C4—H4A119.7N2—C18—H18B109.2
C4—C5—C6120.65 (7)C19—C18—H18B109.2
C4—C5—H5A119.7H18A—C18—H18B107.9
C6—C5—H5A119.7C20—C19—C21111.16 (7)
N1—C6—C5116.55 (6)C20—C19—C18111.05 (7)
N1—C6—C1124.78 (6)C21—C19—C18108.91 (7)
C5—C6—C1118.67 (6)C20—C19—H19A108.5
N1—C7—N4120.12 (6)C21—C19—H19A108.5
N1—C7—C8121.23 (7)C18—C19—H19A108.5
N4—C7—C8118.64 (6)C19—C20—H20A109.5
N3—C8—C9111.13 (6)C19—C20—H20B109.5
N3—C8—C7129.05 (7)H20A—C20—H20B109.5
C9—C8—C7119.81 (6)C19—C20—H20C109.5
N2—C9—C8105.12 (6)H20A—C20—H20C109.5
N2—C9—C1133.65 (7)H20B—C20—H20C109.5
C8—C9—C1121.23 (6)C19—C21—H21A109.5
N3—C10—N2113.54 (7)C19—C21—H21B109.5
N3—C10—H10A123.2H21A—C21—H21B109.5
N2—C10—H10A123.2C19—C21—H21C109.5
N5—C11—C12119.30 (7)H21A—C21—H21C109.5
N5—C11—H11A120.3H21B—C21—H21C109.5
C12—C11—H11A120.3H1W1—O1W—H2WA110.7
C17—C12—C13118.81 (7)H1W1—O1W—H2WB107.9
C7—N4—N5—C11−178.12 (7)N3—C8—C9—N2−0.42 (9)
C6—C1—C2—C33.55 (11)C7—C8—C9—N2178.87 (7)
C9—C1—C2—C3−177.20 (7)N3—C8—C9—C1179.51 (7)
C1—C2—C3—C40.05 (12)C7—C8—C9—C1−1.21 (11)
C2—C3—C4—C5−2.71 (12)C2—C1—C9—N23.78 (14)
C3—C4—C5—C61.68 (12)C6—C1—C9—N2−176.94 (8)
C7—N1—C6—C5−177.76 (7)C2—C1—C9—C8−176.12 (7)
C7—N1—C6—C12.14 (11)C6—C1—C9—C83.17 (10)
C4—C5—C6—N1−178.17 (7)C8—N3—C10—N2−0.36 (9)
C4—C5—C6—C11.94 (11)C9—N2—C10—N30.12 (10)
C2—C1—C6—N1175.61 (7)C18—N2—C10—N3175.72 (7)
C9—C1—C6—N1−3.74 (10)N4—N5—C11—C12178.17 (7)
C2—C1—C6—C5−4.50 (11)N5—C11—C12—C17−174.05 (8)
C9—C1—C6—C5176.15 (7)N5—C11—C12—C134.30 (12)
C6—N1—C7—N4179.21 (7)C17—C12—C13—C141.54 (12)
C6—N1—C7—C80.24 (11)C11—C12—C13—C14−176.82 (8)
N5—N4—C7—N10.18 (11)C12—C13—C14—C150.15 (13)
N5—N4—C7—C8179.17 (7)C13—C14—C15—C16−1.62 (13)
C10—N3—C8—C90.48 (9)C13—C14—C15—Cl1177.25 (7)
C10—N3—C8—C7−178.72 (8)C14—C15—C16—C171.32 (14)
N1—C7—C8—N3178.48 (7)Cl1—C15—C16—C17−177.53 (7)
N4—C7—C8—N3−0.50 (12)C15—C16—C17—C120.44 (13)
N1—C7—C8—C9−0.66 (11)C13—C12—C17—C16−1.84 (12)
N4—C7—C8—C9−179.64 (7)C11—C12—C17—C16176.54 (8)
C10—N2—C9—C80.18 (8)C10—N2—C18—C19−105.84 (9)
C18—N2—C9—C8−175.14 (7)C9—N2—C18—C1968.72 (10)
C10—N2—C9—C1−179.73 (8)N2—C18—C19—C2062.01 (9)
C18—N2—C9—C14.95 (14)N2—C18—C19—C21−175.26 (7)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N4—H1N4···O1Wi0.874 (19)2.559 (18)3.2789 (13)140.2 (14)
O1W—H1W1···N1ii0.832.092.9178 (14)173
C10—H10A···O1Wiii0.932.523.3513 (16)149
C18—H18B···O1Wiii0.972.593.4776 (14)153

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: IS2658).

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