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

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ISSN: 2056-9890

N-(2-Chloro­quinolin-3-ylmethyl­ene)aniline

aDepartment of Chemistry, Karnatak Science College, Dharwad 580001, Karnataka, India, and bDepartment of Chemistry, NDHU Shoufeng, Hualien 947, Taiwan
*Correspondence e-mail: drgmk256@gmail.com

(Received 13 June 2007; accepted 30 November 2007; online 12 December 2007)

The title compound, C16H11ClN2, displays a trans configuration across the C=N bond and a transoid arrangement across the quinoline ring and the azomethine C atom. This arrangement facilitates C—H⋯Cl interactions. The packing in the crystal structure is due to inter­molecular C—H⋯π and Cl⋯π (3.52 and 3.84 Å) inter­actions. The dihedral angle between the least-squares planes of 2-chloro­quinoline and phenyl­amine is 16.61 (2)°.

Related literature

For the importance of chloro-substituted quinolines, see: Meth-Cohn et al. (1981[Meth-Cohn, O., Tarnowski, B., Hayear, R., Keyzad, A. & Rhouti, S. (1981). J. Chem. Soc. Perkin Trans. 1, pp. 2509-2517.]); Rajendran & Karavembu (2002[Rajendran, P. & Karavembu, R. (2002). Indian J. Chem. Sect. B, 41, 222-224.]); Dutta et al. (2002[Dutta, N. J., Khunt, R. C. & Parikh, A. R. (2002). Ind. J. Chem. 41B, 433-435.]). For chloro-substituted benzyl­idine anilines see: Prasanna & Guru Row (2000[Prasanna, M. D. & Guru Row, T. N. (2000). Cryst. Eng. 3, 135-154.]).

For related literature, see: Meth-Cohn & Narine (1978[Meth-Cohn, O. & Narine, B. (1978). Tetrahedron. Lett. pp. 2045-2048.]); Umezawa et al. (1998[Umezawa, Y., Tsuboyama, S., Honda, K., Uzawa, J. & Nishio, M. (1998). Bull. Chem. Soc. Jpn, 71, 1207-1210.], 1999[Umezawa, Y., Tsuboyama, S., Takahashi, H. & Nishio, M. (1999). Tetrahedron, 55, 10047-10056.]).

[Scheme 1]

Experimental

Crystal data
  • C16H11ClN2

  • Mr = 266.72

  • Orthorhombic, P 21 21 21

  • a = 6.0069 (3) Å

  • b = 11.6812 (6) Å

  • c = 18.3798 (9) Å

  • V = 1289.67 (11) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.28 mm−1

  • T = 273 (2) K

  • 0.40 × 0.11 × 0.09 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.880, Tmax = 0.975

  • 13778 measured reflections

  • 2272 independent reflections

  • 1984 reflections with I > 2σ(I)

  • Rint = 0.031

Refinement
  • R[F2 > 2σ(F2)] = 0.024

  • wR(F2) = 0.060

  • S = 1.01

  • 2272 reflections

  • 217 parameters

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

  • Δρmax = 0.10 e Å−3

  • Δρmin = −0.13 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 929 Friedel pairs

  • Flack parameter: −0.05 (5)

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of the C2–C7 ring.

D—H⋯A D—H H⋯A DA D—H⋯A
C10—H10⋯Cl1 0.997 (17) 2.68 3.0667 104
C6—H6⋯Cg2i 0.956 (19) 2.96 3.755 (1) 142
Symmetry code: (i) [-x-1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 1999[Bruker (1999). SHELXTL, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1999[Bruker (1999). SHELXTL, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXL97 and SHELXS97. University of Göttingen, Germany.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXL97 and SHELXS97. University of Göttingen, Germany.]); molecular graphics: SHELXTL (Bruker, 1999[Bruker (1999). SHELXTL, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

2-chloro substituted quinolines are vital synthetic intermediates in the construction of a large number of linearly fused tri- and tetra - cyclic quinolines studied for the DNA intercalating properties (Meth-Cohn et al., 1981; Rajendran & Karavembu, 2002; Dutta et al., 2002). Several interesting structural features associated with chloro substituted Benzilidine anilines, like polymorphism, twisting of aryl moieties, presence of weak Cl···π interactions have come to light through their diffraction studies (Prasanna & Guru Row, 2000).

Many schiff bases have been synthesized from 2-chloro-3-formyl-quinoline (Meth-Cohn & Narine, 1978), for studying nonlinear Optical phenomenon arising due to the extended conjugation within the molecule. It is of interest to know the conformation around the azomethine double bond which restricts the free rotation and causes changes in dipole moment manifestations.

The prefered trans conformer is stabilized due to C—H···Cl (2.676 Å) intramolecular interaction (Fig. 1). Molecular packing formed along a axis organizes the molecules in a Zigzag pattern due to C—H..π (2.962 Å) and Cl···π (3.521°, 3.845°) intermolecular interactions.(Fig.2) The dihedral angle between the least squares planes of 2-chloro-quinoline and the phenylamine is 16.61 (2)°.

Related literature top

For the importance of chloro-substituted quinoline, see: Meth-Cohn et al. (1981); Rajendran & Karavembu (2002); Dutta et al. (2002). For chloro-substituted benzylidine anilines see: Prasanna & Guru Row (2000).

For related literature, see: Meth-Cohn & Narine (1978); Umezawa et al. (1998, 1999).

Experimental top

A mixture of 2-chloro-3-formyl-quinoline (1.064 g, 0.004 mol) and aniline (0.37 ml,0.004 mol) in ethanol-acetic acid mixture (20 ml, 2:1) was stirred at room temperature for 6 h. After the completion of the reaction (6 h), the separated solid was filtered and washed with excess of cold alcohol.It was dried and crystallized from ethanol (yield = 92%, M.P=435 K). Colourless rectangular crystals were grown from benzene and etyl acetate solvents (1:1, v/v) by slow evaporation method at room temperature.

Refinement top

All H atoms atoms were located in difference fourier map and refined isotropically, with Uiso(H)=1.2Ueq(C).

Structure description top

2-chloro substituted quinolines are vital synthetic intermediates in the construction of a large number of linearly fused tri- and tetra - cyclic quinolines studied for the DNA intercalating properties (Meth-Cohn et al., 1981; Rajendran & Karavembu, 2002; Dutta et al., 2002). Several interesting structural features associated with chloro substituted Benzilidine anilines, like polymorphism, twisting of aryl moieties, presence of weak Cl···π interactions have come to light through their diffraction studies (Prasanna & Guru Row, 2000).

Many schiff bases have been synthesized from 2-chloro-3-formyl-quinoline (Meth-Cohn & Narine, 1978), for studying nonlinear Optical phenomenon arising due to the extended conjugation within the molecule. It is of interest to know the conformation around the azomethine double bond which restricts the free rotation and causes changes in dipole moment manifestations.

The prefered trans conformer is stabilized due to C—H···Cl (2.676 Å) intramolecular interaction (Fig. 1). Molecular packing formed along a axis organizes the molecules in a Zigzag pattern due to C—H..π (2.962 Å) and Cl···π (3.521°, 3.845°) intermolecular interactions.(Fig.2) The dihedral angle between the least squares planes of 2-chloro-quinoline and the phenylamine is 16.61 (2)°.

For the importance of chloro-substituted quinoline, see: Meth-Cohn et al. (1981); Rajendran & Karavembu (2002); Dutta et al. (2002). For chloro-substituted benzylidine anilines see: Prasanna & Guru Row (2000).

For related literature, see: Meth-Cohn & Narine (1978); Umezawa et al. (1998, 1999).

Computing details top

Data collection: SMART (Bruker, 1999); cell refinement: SMART (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1999); software used to prepare material for publication: SHELXTL (Bruker, 1999).

Figures top
[Figure 1] Fig. 1. ORTEP diagram of the molecule in asymmetric unit with 50% probability displacement ellipsoids showing the atom-numbering scheme and C—H···Cl interaction.
[Figure 2] Fig. 2. Molecular packing due to C—H···π and Cl···π interactions along a axis.
N-(2-Chloroquinolin-3-ylmethylene)aniline top
Crystal data top
C16H11ClN2Dx = 1.374 Mg m3
Mr = 266.72Melting point: 162 K
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P2ac2abCell parameters from 3933 reflections
a = 6.0069 (3) Åθ = 2.2–22.3°
b = 11.6812 (6) ŵ = 0.28 mm1
c = 18.3798 (9) ÅT = 273 K
V = 1289.67 (11) Å3Rectangular, colourless
Z = 40.40 × 0.11 × 0.09 mm
F(000) = 552
Data collection top
CCD area-detector
diffractometer
2272 independent reflections
Radiation source: fine-focus sealed tube1984 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.031
φ and ω scansθmax = 25.0°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 77
Tmin = 0.880, Tmax = 0.975k = 1313
13778 measured reflectionsl = 2121
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.024 w = 1/[σ2(Fo2) + (0.0303P)2 + 0.1031P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.060(Δ/σ)max < 0.001
S = 1.01Δρmax = 0.10 e Å3
2272 reflectionsΔρmin = 0.13 e Å3
217 parametersExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.0221 (13)
Primary atom site location: structure-invariant direct methodsAbsolute structure: Flack (1983), 929 Friedel pairs
Secondary atom site location: difference Fourier mapAbsolute structure parameter: 0.05 (5)
Crystal data top
C16H11ClN2V = 1289.67 (11) Å3
Mr = 266.72Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 6.0069 (3) ŵ = 0.28 mm1
b = 11.6812 (6) ÅT = 273 K
c = 18.3798 (9) Å0.40 × 0.11 × 0.09 mm
Data collection top
CCD area-detector
diffractometer
2272 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1984 reflections with I > 2σ(I)
Tmin = 0.880, Tmax = 0.975Rint = 0.031
13778 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.024H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.060Δρmax = 0.10 e Å3
S = 1.01Δρmin = 0.13 e Å3
2272 reflectionsAbsolute structure: Flack (1983), 929 Friedel pairs
217 parametersAbsolute structure parameter: 0.05 (5)
0 restraints
Special details top

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
Cl10.09134 (8)0.27844 (4)0.72352 (2)0.06349 (15)
N10.2433 (2)0.10138 (11)0.79120 (7)0.0480 (3)
N20.4029 (2)0.27821 (11)0.89186 (6)0.0485 (3)
C10.0786 (3)0.17247 (13)0.79054 (8)0.0460 (4)
C20.2429 (3)0.01865 (13)0.84434 (8)0.0457 (4)
C30.4204 (3)0.05994 (15)0.84716 (10)0.0560 (4)
H30.533 (3)0.0514 (14)0.8119 (10)0.059 (5)*
C40.4242 (4)0.14343 (16)0.89875 (10)0.0626 (5)
H40.552 (4)0.1966 (17)0.9029 (11)0.082 (6)*
C50.2529 (4)0.15120 (16)0.95073 (11)0.0640 (5)
H50.266 (3)0.2075 (15)0.9847 (10)0.067 (5)*
C60.0802 (4)0.07688 (14)0.94957 (10)0.0559 (4)
H60.036 (3)0.0804 (14)0.9851 (10)0.062 (5)*
C70.0705 (3)0.01022 (13)0.89623 (8)0.0456 (4)
C80.1042 (3)0.09005 (13)0.89156 (9)0.0475 (4)
H80.228 (3)0.0865 (14)0.9251 (9)0.055 (5)*
C90.1048 (3)0.17368 (13)0.83936 (8)0.0441 (4)
C100.2813 (3)0.26074 (14)0.83700 (9)0.0481 (4)
H100.300 (3)0.3049 (14)0.7910 (10)0.057 (5)*
C110.5640 (3)0.36654 (13)0.88976 (8)0.0454 (4)
C120.7579 (3)0.35109 (15)0.93006 (9)0.0505 (4)
H120.773 (3)0.2826 (14)0.9550 (9)0.049 (4)*
C130.9205 (4)0.43458 (17)0.93071 (10)0.0602 (5)
H131.044 (3)0.4184 (14)0.9571 (10)0.057 (5)*
C140.8916 (4)0.53449 (17)0.89224 (11)0.0662 (5)
H141.005 (4)0.5924 (17)0.8927 (11)0.082 (7)*
C150.6971 (4)0.55175 (17)0.85356 (11)0.0630 (5)
H150.672 (3)0.6234 (17)0.8277 (11)0.070 (6)*
C160.5336 (3)0.46919 (15)0.85239 (9)0.0522 (4)
H160.395 (3)0.4831 (15)0.8266 (9)0.060 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0701 (3)0.0640 (3)0.0564 (2)0.0052 (3)0.0084 (2)0.0134 (2)
N10.0461 (7)0.0535 (7)0.0446 (7)0.0035 (7)0.0045 (6)0.0039 (6)
N20.0494 (7)0.0496 (7)0.0464 (7)0.0009 (8)0.0015 (7)0.0011 (6)
C10.0509 (9)0.0476 (8)0.0396 (8)0.0064 (8)0.0009 (8)0.0037 (6)
C20.0476 (9)0.0468 (9)0.0428 (8)0.0038 (8)0.0015 (8)0.0092 (7)
C30.0501 (10)0.0625 (11)0.0553 (10)0.0012 (10)0.0003 (10)0.0078 (9)
C40.0606 (11)0.0603 (11)0.0668 (11)0.0096 (11)0.0063 (11)0.0058 (9)
C50.0800 (14)0.0523 (10)0.0598 (11)0.0048 (12)0.0020 (11)0.0055 (9)
C60.0668 (12)0.0505 (10)0.0503 (10)0.0018 (10)0.0044 (10)0.0004 (7)
C70.0518 (10)0.0433 (8)0.0417 (8)0.0036 (8)0.0019 (9)0.0070 (7)
C80.0490 (9)0.0496 (9)0.0440 (9)0.0044 (9)0.0068 (9)0.0065 (7)
C90.0471 (9)0.0458 (8)0.0394 (7)0.0024 (8)0.0004 (8)0.0054 (6)
C100.0519 (10)0.0512 (9)0.0413 (8)0.0005 (8)0.0015 (8)0.0021 (7)
C110.0475 (9)0.0502 (9)0.0386 (7)0.0010 (8)0.0040 (7)0.0056 (7)
C120.0526 (10)0.0528 (10)0.0461 (9)0.0046 (9)0.0005 (8)0.0050 (8)
C130.0459 (10)0.0762 (13)0.0583 (10)0.0014 (11)0.0034 (10)0.0122 (9)
C140.0656 (13)0.0665 (12)0.0664 (12)0.0156 (12)0.0120 (12)0.0075 (10)
C150.0779 (14)0.0535 (11)0.0575 (11)0.0070 (10)0.0076 (10)0.0027 (9)
C160.0572 (12)0.0543 (10)0.0451 (9)0.0017 (9)0.0005 (8)0.0006 (8)
Geometric parameters (Å, º) top
Cl1—C11.7479 (16)C7—C81.406 (3)
N1—C11.291 (2)C8—C91.369 (2)
N1—C21.374 (2)C8—H80.968 (18)
N2—C101.261 (2)C9—C101.470 (2)
N2—C111.415 (2)C10—H100.997 (17)
C1—C91.421 (2)C11—C121.392 (2)
C2—C31.408 (3)C11—C161.394 (2)
C2—C71.411 (2)C12—C131.380 (3)
C3—C41.360 (3)C12—H120.926 (16)
C3—H30.940 (19)C13—C141.375 (3)
C4—C51.407 (3)C13—H130.906 (19)
C4—H40.99 (2)C14—C151.383 (3)
C5—C61.353 (3)C14—H140.96 (2)
C5—H50.910 (18)C15—C161.377 (3)
C6—C71.414 (2)C15—H150.97 (2)
C6—H60.956 (19)C16—H160.972 (19)
C1—N1—C2117.24 (14)C7—C8—H8120.4 (10)
C10—N2—C11119.48 (13)C8—C9—C1115.67 (15)
N1—C1—C9126.46 (14)C8—C9—C10121.10 (15)
N1—C1—Cl1115.37 (12)C1—C9—C10123.19 (14)
C9—C1—Cl1118.16 (12)N2—C10—C9120.39 (15)
N1—C2—C3118.91 (16)N2—C10—H10122.0 (10)
N1—C2—C7122.05 (15)C9—C10—H10117.7 (10)
C3—C2—C7119.04 (16)C12—C11—C16118.91 (17)
C4—C3—C2120.39 (19)C12—C11—N2117.60 (14)
C4—C3—H3123.0 (11)C16—C11—N2123.42 (15)
C2—C3—H3116.6 (11)C13—C12—C11120.33 (17)
C3—C4—C5120.5 (2)C13—C12—H12122.6 (11)
C3—C4—H4121.1 (12)C11—C12—H12117.1 (11)
C5—C4—H4118.3 (12)C14—C13—C12120.4 (2)
C6—C5—C4120.57 (18)C14—C13—H13123.8 (11)
C6—C5—H5122.9 (13)C12—C13—H13115.8 (11)
C4—C5—H5116.6 (13)C13—C14—C15119.7 (2)
C5—C6—C7120.28 (19)C13—C14—H14120.1 (13)
C5—C6—H6121.4 (11)C15—C14—H14120.2 (13)
C7—C6—H6118.3 (11)C16—C15—C14120.6 (2)
C8—C7—C2117.38 (14)C16—C15—H15118.8 (12)
C8—C7—C6123.38 (17)C14—C15—H15120.6 (12)
C2—C7—C6119.24 (18)C15—C16—C11120.08 (18)
C9—C8—C7121.20 (16)C15—C16—H16120.1 (11)
C9—C8—H8118.4 (10)C11—C16—H16119.8 (11)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10···Cl10.997 (17)2.683.0667104
C6—H6···Cg2i0.956 (19)2.963.755 (1)142
Symmetry code: (i) x1, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC16H11ClN2
Mr266.72
Crystal system, space groupOrthorhombic, P212121
Temperature (K)273
a, b, c (Å)6.0069 (3), 11.6812 (6), 18.3798 (9)
V3)1289.67 (11)
Z4
Radiation typeMo Kα
µ (mm1)0.28
Crystal size (mm)0.40 × 0.11 × 0.09
Data collection
DiffractometerCCD area-detector
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.880, 0.975
No. of measured, independent and
observed [I > 2σ(I)] reflections
13778, 2272, 1984
Rint0.031
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.024, 0.060, 1.01
No. of reflections2272
No. of parameters217
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.10, 0.13
Absolute structureFlack (1983), 929 Friedel pairs
Absolute structure parameter0.05 (5)

Computer programs: SMART (Bruker, 1999), SAINT (Bruker, 1999), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10···Cl10.997 (17)2.683.0667104
C6—H6···Cg2i0.956 (19)2.963.755 (1)142
Symmetry code: (i) x1, y+1/2, z+1/2.
 

Acknowledgements

The authors thank National Dong Hwa University, Taiwan, for use of the CCD X-ray facility and FAB-MS, the University Sophisticated Instrumentation Centre, Karnatak University, Dharwad, for help with the IR and NMR data. RGK thanks Karnatak University and Karnatak Science College, Dharwad, for a University Research Studentship.

References

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