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Acta Crystallogr Sect E Struct Rep Online. 2010 July 1; 66(Pt 7): o1823.
Published online 2010 June 26. doi:  10.1107/S160053681002430X
PMCID: PMC3007064

2-Chloro-7-methyl-12-phenyldibenzo[b,g][1,8]naphthyridin-11(6H)-one

Abstract

In the title compound, C23H15ClN2O, the fused ring system is planar: the deviation of all the non-H atoms from the plane through all four fused rings is less than 0.31 Å. The plane of the phenyl ring is inclined at 71.78 (5)° to the mean plane of the 1,8-naphthrydine ring system. The crystal structure is devoid of any classical hydrogen bonds but π–π inter­actions are present.

Related literature

For the biological activity of [1,8]naphthyridine derivatives, see: Egawa et al. (1984 [triangle]); Cooper et al. (1992 [triangle]); Chen et al. (1997) [triangle]; Balin & Tan (1984 [triangle]); Nadaraj et al. (2009 [triangle]); Kuroda et al. (1992 [triangle]). For the synthesis of the title compound, see: Manoj et al. (2009 [triangle]). For the crystal structures of other naphthrydine derivatives, see: Sivakumar et al. (2003 [triangle]); Seebacher et al. (2010 [triangle]). For bond-length data, see: Allen et al. (1987 [triangle]).

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Object name is e-66-o1823-scheme1.jpg

Experimental

Crystal data

  • C23H15ClN2O
  • M r = 370.82
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1823-efi1.jpg
  • a = 8.2434 (2) Å
  • b = 8.5528 (2) Å
  • c = 13.0740 (3) Å
  • α = 89.446 (1)°
  • β = 74.362 (1)°
  • γ = 77.672 (1)°
  • V = 866.06 (4) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.24 mm−1
  • T = 293 K
  • 0.25 × 0.24 × 0.23 mm

Data collection

  • Bruker SMART APEXII area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2007 [triangle]) T min = 0.943, T max = 0.947
  • 21083 measured reflections
  • 5019 independent reflections
  • 4047 reflections with I > 2σ(I)
  • R int = 0.025

Refinement

  • R[F 2 > 2σ(F 2)] = 0.044
  • wR(F 2) = 0.138
  • S = 1.00
  • 5019 reflections
  • 245 parameters
  • H-atom parameters constrained
  • Δρmax = 0.37 e Å−3
  • Δρmin = −0.35 e Å−3

Data collection: APEX2 (Bruker, 2007 [triangle]); cell refinement: SAINT (Bruker, 2007 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 [triangle]).

Table 1
π–π inter­actions (Å).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053681002430X/su2185sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053681002430X/su2185Isup2.hkl

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

Acknowledgments

DV acknowledges the Department of Science and Technology (DST) for providing computing facilities under major research projects and for financial support under the UGC-SAP and DST-FIST programs.

supplementary crystallographic information

Comment

In general, nitrogen containing heterocyclic compounds play important roles in biological activities. Among such compounds, [1,8]naphthyridine derivatives represent the most active class of compounds possessing a wide spectrum of biological activities, such as antibacterial (Miyamoto et al., 1984, Cooper et al., 1992), antitumour (Chen et al., 1997), antimalarial (Balin et al., 1984), antifungal (Nadaraj et al., 2009), anti-inflammatory (Kuroda et al., 1992), antihypertensive activities etc. This paper describes the crystal structure of the title compound, which will help us in our studies on drug design.

The title compound consists of a [1,8]napthyridine core with methyl, chloro-phenyl and phenyl group substituents (Fig. 1). The dihedral angle between the two fused rings of the napthyridine moiety is found to be 3.08 (3)°, indicating that it is almost planar. The phenyl ring is inclined to the mean plane of the [1,8]naphthrydine ring system by 72.51 (3)°. The bond lengths of the formal single bonds, and C2—Cl1 = 1.7392 (14) and C12–O1 = 1.2240 (14) Å, are in normal ranges (Allen et al., 1987), and similar to those observed in other naphthrydine derivatives (Sivakumar et al., 2003; Seebacher et al., 2010).

The crystal packing of the molecules in the crystal is influenced by π–π interactions and van der Waals forces (Fig. 2 and Table 1).

Footnote for Table 1: Symmetry codes : (i) -x+2, -y+1, -z; (ii) -x+2, -y, -z.

Experimental

The title compund was synthesized according to the published procedure (Manoj et al., 2009). 2[(2'-Benzoyl-4'-chlorophenyl)amino]-4-chloroquinoline (2 mmol) was added to polyphosphoric acid (6 g of P2O5 in 3 ml of H3PO4) and heated at 478–483 K for 5 h. The reaction was monitored by using TLC. After completion of the reaction, the reaction mixture was poured into ice water and extracted with ethyl acetate. It was then purified by column chromatography using silica gel and the product eluted with a petroleum ether:ethyl acetate (96:4) mixture, to give the title compound as a pale yellow solid. It was recrystallized using methanol.

Refinement

The H-atoms were positioned geometrically and treated as riding atoms: C—H = 0.93 Å H-aromatic, C—H = 0.96 Å H-methyl, and N—H = 0.86 Å, with Uiso = k×Ueq(parent C or N-atom), where k = 1.5 for methyl H-atoms, and = 1.2 for all other H-atoms.

Figures

Fig. 1.
View of the title molecule, showing the thermal ellipsoids drawn at the 50% probability level.
Fig. 2.
View of the crystal packing of the title compound, illustrating the π–π interactions as dotted lines [the centroids are marked by large black dots; see Table 1 for details].

Crystal data

C23H15ClN2OZ = 2
Mr = 370.82F(000) = 384
Triclinic, P1Dx = 1.422 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.2434 (2) ÅCell parameters from 5019 reflections
b = 8.5528 (2) Åθ = 1.6–30.0°
c = 13.0740 (3) ŵ = 0.24 mm1
α = 89.446 (1)°T = 293 K
β = 74.362 (1)°Block, pale yellow
γ = 77.672 (1)°0.25 × 0.24 × 0.23 mm
V = 866.06 (4) Å3

Data collection

Bruker SMART APEXII area-detector diffractometer5019 independent reflections
Radiation source: fine-focus sealed tube4047 reflections with I > 2σ(I)
graphiteRint = 0.025
ω and [var phi] scansθmax = 30.0°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2007)h = −11→11
Tmin = 0.943, Tmax = 0.947k = −12→12
21083 measured reflectionsl = −17→18

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)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.138H-atom parameters constrained
S = 1.00w = 1/[σ2(Fo2) + (0.0812P)2 + 0.1735P] where P = (Fo2 + 2Fc2)/3
5019 reflections(Δ/σ)max < 0.001
245 parametersΔρmax = 0.37 e Å3
0 restraintsΔρmin = −0.34 e Å3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Cl10.43107 (6)0.82442 (6)0.41605 (3)0.06692 (16)
C80.97978 (14)0.28540 (13)0.08976 (9)0.0295 (2)
N10.75659 (13)0.43848 (12)0.01596 (8)0.0347 (2)
C60.75767 (14)0.49589 (13)0.19809 (9)0.0321 (2)
C70.91173 (14)0.37615 (13)0.18528 (9)0.0303 (2)
C111.19508 (14)0.07433 (13)−0.03719 (9)0.0318 (2)
N20.96411 (13)0.24442 (12)−0.08970 (8)0.0349 (2)
H20.91040.2694−0.13760.042*
C50.68564 (14)0.52218 (14)0.11069 (9)0.0329 (2)
C90.89694 (14)0.32538 (13)0.00739 (9)0.0298 (2)
O11.18861 (13)0.08963 (12)0.14332 (7)0.0456 (2)
C161.17758 (17)0.05651 (15)−0.22018 (10)0.0375 (3)
C121.12754 (15)0.14578 (14)0.07187 (9)0.0318 (2)
C101.11201 (14)0.12564 (13)−0.11549 (9)0.0317 (2)
C151.32690 (18)−0.06129 (16)−0.24169 (11)0.0443 (3)
H151.3730−0.1075−0.31030.053*
C191.15161 (16)0.40958 (15)0.25824 (10)0.0390 (3)
H191.19850.45510.19530.047*
C180.99944 (15)0.35745 (14)0.27169 (9)0.0334 (2)
C131.34488 (16)−0.04709 (15)−0.06305 (11)0.0392 (3)
H131.3998−0.0829−0.01100.047*
C10.67473 (16)0.59156 (15)0.29368 (10)0.0388 (3)
H10.71900.57540.35220.047*
C40.53475 (16)0.64433 (16)0.12077 (12)0.0423 (3)
H40.48680.66190.06380.051*
C230.92949 (19)0.29264 (18)0.36673 (11)0.0451 (3)
H230.82520.26110.37750.054*
C171.0871 (2)0.11093 (18)−0.30353 (10)0.0472 (3)
H17A1.16010.0680−0.37210.071*
H17B1.06160.2259−0.30300.071*
H17C0.98150.0738−0.28900.071*
C20.53032 (17)0.70682 (16)0.29904 (11)0.0424 (3)
C201.23394 (19)0.39418 (18)0.33819 (12)0.0494 (3)
H201.33510.43080.32930.059*
C211.1663 (2)0.3246 (2)0.43107 (12)0.0584 (4)
H211.22370.31140.48390.070*
C141.41133 (18)−0.11368 (17)−0.16453 (12)0.0465 (3)
H141.5121−0.1933−0.18180.056*
C221.0139 (2)0.2747 (2)0.44566 (12)0.0584 (4)
H220.96780.22880.50860.070*
C30.45924 (17)0.73618 (17)0.21266 (13)0.0468 (3)
H30.36180.81740.21810.056*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cl10.0572 (2)0.0680 (3)0.0571 (2)0.00139 (19)0.00421 (18)−0.01642 (19)
C80.0295 (5)0.0310 (5)0.0304 (5)−0.0063 (4)−0.0127 (4)0.0058 (4)
N10.0342 (5)0.0353 (5)0.0368 (5)−0.0039 (4)−0.0166 (4)0.0056 (4)
C60.0303 (5)0.0321 (5)0.0349 (5)−0.0068 (4)−0.0106 (4)0.0034 (4)
C70.0309 (5)0.0330 (5)0.0305 (5)−0.0087 (4)−0.0130 (4)0.0063 (4)
C110.0307 (5)0.0314 (5)0.0345 (5)−0.0076 (4)−0.0103 (4)0.0035 (4)
N20.0372 (5)0.0389 (5)0.0299 (5)−0.0033 (4)−0.0155 (4)0.0034 (4)
C50.0309 (5)0.0322 (5)0.0382 (6)−0.0067 (4)−0.0140 (4)0.0053 (4)
C90.0318 (5)0.0313 (5)0.0298 (5)−0.0080 (4)−0.0133 (4)0.0066 (4)
O10.0491 (5)0.0473 (5)0.0404 (5)0.0056 (4)−0.0247 (4)0.0027 (4)
C160.0418 (6)0.0399 (6)0.0325 (6)−0.0139 (5)−0.0091 (5)0.0031 (4)
C120.0315 (5)0.0326 (5)0.0340 (5)−0.0059 (4)−0.0143 (4)0.0053 (4)
C100.0320 (5)0.0317 (5)0.0324 (5)−0.0092 (4)−0.0091 (4)0.0041 (4)
C150.0437 (7)0.0443 (7)0.0405 (6)−0.0096 (5)−0.0038 (5)−0.0056 (5)
C190.0381 (6)0.0406 (6)0.0405 (6)−0.0065 (5)−0.0159 (5)0.0020 (5)
C180.0359 (5)0.0350 (5)0.0305 (5)−0.0035 (4)−0.0144 (4)0.0003 (4)
C130.0341 (6)0.0363 (6)0.0474 (7)−0.0034 (4)−0.0147 (5)0.0014 (5)
C10.0369 (6)0.0410 (6)0.0377 (6)−0.0077 (5)−0.0092 (5)−0.0008 (5)
C40.0352 (6)0.0403 (6)0.0525 (7)−0.0018 (5)−0.0190 (5)0.0055 (5)
C230.0489 (7)0.0552 (8)0.0357 (6)−0.0156 (6)−0.0161 (5)0.0082 (5)
C170.0581 (8)0.0523 (7)0.0315 (6)−0.0100 (6)−0.0144 (6)0.0013 (5)
C20.0353 (6)0.0403 (6)0.0466 (7)−0.0070 (5)−0.0033 (5)−0.0034 (5)
C200.0447 (7)0.0542 (8)0.0553 (8)−0.0081 (6)−0.0259 (6)−0.0069 (6)
C210.0677 (10)0.0708 (10)0.0445 (8)−0.0060 (8)−0.0353 (7)−0.0027 (7)
C140.0369 (6)0.0438 (7)0.0534 (8)−0.0012 (5)−0.0088 (6)−0.0056 (6)
C220.0709 (10)0.0748 (11)0.0352 (7)−0.0160 (8)−0.0242 (7)0.0126 (7)
C30.0319 (6)0.0414 (7)0.0624 (9)−0.0008 (5)−0.0106 (6)0.0006 (6)

Geometric parameters (Å, °)

Cl1—C21.7392 (14)C19—C201.3828 (18)
C8—C71.3899 (15)C19—C181.3863 (17)
C8—C91.4256 (14)C19—H190.9300
C8—C121.4816 (15)C18—C231.3859 (18)
N1—C91.3196 (14)C13—C141.3690 (19)
N1—C51.3551 (15)C13—H130.9300
C6—C51.4187 (16)C1—C21.3598 (18)
C6—C11.4210 (16)C1—H10.9300
C6—C71.4223 (15)C4—C31.362 (2)
C7—C181.4873 (15)C4—H40.9300
C11—C101.3965 (16)C23—C221.3824 (19)
C11—C131.3971 (16)C23—H230.9300
C11—C121.4697 (16)C17—H17A0.9600
N2—C91.3681 (15)C17—H17B0.9600
N2—C101.3741 (15)C17—H17C0.9600
N2—H20.8600C2—C31.404 (2)
C5—C41.4197 (16)C20—C211.379 (2)
O1—C121.2240 (14)C20—H200.9300
C16—C151.3780 (18)C21—C221.376 (2)
C16—C101.4126 (16)C21—H210.9300
C16—C171.4970 (18)C14—H140.9300
C15—C141.393 (2)C22—H220.9300
C15—H150.9300C3—H30.9300
C7—C8—C9117.71 (10)C23—C18—C7121.22 (11)
C7—C8—C12123.22 (9)C19—C18—C7119.52 (10)
C9—C8—C12119.00 (10)C14—C13—C11120.42 (12)
C9—N1—C5117.25 (10)C14—C13—H13119.8
C5—C6—C1118.78 (10)C11—C13—H13119.8
C5—C6—C7118.27 (10)C2—C1—C6119.61 (12)
C1—C6—C7122.95 (10)C2—C1—H1120.2
C8—C7—C6118.53 (10)C6—C1—H1120.2
C8—C7—C18122.12 (10)C3—C4—C5120.95 (12)
C6—C7—C18119.28 (10)C3—C4—H4119.5
C10—C11—C13119.38 (11)C5—C4—H4119.5
C10—C11—C12121.14 (10)C22—C23—C18120.35 (13)
C13—C11—C12119.48 (11)C22—C23—H23119.8
C9—N2—C10124.08 (10)C18—C23—H23119.8
C9—N2—H2118.0C16—C17—H17A109.5
C10—N2—H2118.0C16—C17—H17B109.5
N1—C5—C6123.07 (10)H17A—C17—H17B109.5
N1—C5—C4117.74 (11)C16—C17—H17C109.5
C6—C5—C4119.16 (11)H17A—C17—H17C109.5
N1—C9—N2115.15 (10)H17B—C17—H17C109.5
N1—C9—C8125.05 (10)C1—C2—C3122.28 (12)
N2—C9—C8119.80 (10)C1—C2—Cl1119.20 (11)
C15—C16—C10117.34 (11)C3—C2—Cl1118.51 (10)
C15—C16—C17122.02 (12)C21—C20—C19120.08 (13)
C10—C16—C17120.64 (11)C21—C20—H20120.0
O1—C12—C11121.25 (11)C19—C20—H20120.0
O1—C12—C8122.72 (11)C22—C21—C20120.06 (13)
C11—C12—C8116.02 (9)C22—C21—H21120.0
N2—C10—C11119.27 (10)C20—C21—H21120.0
N2—C10—C16119.86 (11)C13—C14—C15119.50 (12)
C11—C10—C16120.87 (11)C13—C14—H14120.3
C16—C15—C14122.47 (12)C15—C14—H14120.3
C16—C15—H15118.8C21—C22—C23120.02 (14)
C14—C15—H15118.8C21—C22—H22120.0
C20—C19—C18120.20 (13)C23—C22—H22120.0
C20—C19—H19119.9C4—C3—C2119.20 (12)
C18—C19—H19119.9C4—C3—H3120.4
C23—C18—C19119.24 (11)C2—C3—H3120.4
C9—C8—C7—C64.14 (15)C13—C11—C10—C16−0.06 (17)
C12—C8—C7—C6−172.83 (10)C12—C11—C10—C16179.99 (10)
C9—C8—C7—C18−172.72 (10)C15—C16—C10—N2179.56 (11)
C12—C8—C7—C1810.31 (17)C17—C16—C10—N2−0.24 (17)
C5—C6—C7—C8−3.06 (16)C15—C16—C10—C11−0.77 (17)
C1—C6—C7—C8177.96 (10)C17—C16—C10—C11179.43 (11)
C5—C6—C7—C18173.90 (10)C10—C16—C15—C140.73 (19)
C1—C6—C7—C18−5.09 (17)C17—C16—C15—C14−179.47 (13)
C9—N1—C5—C61.61 (17)C20—C19—C18—C231.18 (19)
C9—N1—C5—C4179.91 (10)C20—C19—C18—C7179.49 (12)
C1—C6—C5—N1179.14 (11)C8—C7—C18—C23−111.25 (14)
C7—C6—C5—N10.11 (17)C6—C7—C18—C2371.91 (15)
C1—C6—C5—C40.86 (17)C8—C7—C18—C1970.48 (15)
C7—C6—C5—C4−178.16 (10)C6—C7—C18—C19−106.37 (13)
C5—N1—C9—N2−179.86 (10)C10—C11—C13—C140.97 (19)
C5—N1—C9—C8−0.39 (17)C12—C11—C13—C14−179.07 (11)
C10—N2—C9—N1178.18 (10)C5—C6—C1—C2−0.80 (18)
C10—N2—C9—C8−1.32 (17)C7—C6—C1—C2178.18 (11)
C7—C8—C9—N1−2.55 (17)N1—C5—C4—C3−178.17 (12)
C12—C8—C9—N1174.55 (10)C6—C5—C4—C30.19 (19)
C7—C8—C9—N2176.90 (10)C19—C18—C23—C22−2.4 (2)
C12—C8—C9—N2−6.00 (16)C7—C18—C23—C22179.30 (13)
C10—C11—C12—O1171.91 (11)C6—C1—C2—C3−0.3 (2)
C13—C11—C12—O1−8.05 (17)C6—C1—C2—Cl1−179.41 (9)
C10—C11—C12—C8−6.49 (16)C18—C19—C20—C211.0 (2)
C13—C11—C12—C8173.55 (10)C19—C20—C21—C22−1.9 (2)
C7—C8—C12—O18.09 (18)C11—C13—C14—C15−1.0 (2)
C9—C8—C12—O1−168.84 (11)C16—C15—C14—C130.2 (2)
C7—C8—C12—C11−173.54 (10)C20—C21—C22—C230.7 (3)
C9—C8—C12—C119.53 (15)C18—C23—C22—C211.5 (2)
C9—N2—C10—C114.61 (17)C5—C4—C3—C2−1.3 (2)
C9—N2—C10—C16−175.71 (10)C1—C2—C3—C41.4 (2)
C13—C11—C10—N2179.62 (11)Cl1—C2—C3—C4−179.52 (11)
C12—C11—C10—N2−0.34 (17)

Table 1 π–π interactions (Å). Cg1–Cg4 are the centroids of rings N1/C5–C9, N2/C8–C12, C1–C6 and C10-C16, respectively.

Cg1–Cg4 are the centroids of the N1/C5–C9, N2/C8–C12, C1–C6 and C10-C16 rings, respectively.

Cg1···Cg2i3.7936 (6)
Cg1···Cg4ii3.7721 (7)
Cg2···Cg1i3.7935 (6)
Cg2···Cg2ii3.6542 (6)
Cg2···Cg3i3.8725 (7)
Cg2···Cg4ii3.5506 (7)
Cg3···Cg2i3.8725 (7)
Cg3···Cg4ii3.6485 (8)

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: SU2185).

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