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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 66| Part 12| December 2010| Page o3333
https://doi.org/10.1107/S1600536810048683

2,6-Di­methyl-4-(1,3,4-oxa­diazol-2-yl)quinoline

Artyom G. Kashaev,a Anatoliy V. Zimichev,a Victor B. Rybakov,b* Yurij N. Klimochkina and Margarita N. Zemtsovaa

aSamara State Technical University, Molodogvardeyskay Str. 244, 443100 Samara, Russian Federation, and bDepartment of Chemistry, Moscow State University, 119992 Moscow, Russian Federation
*Correspondence e-mail: rybakov20021@yandex.ru

(Received 13 October 2010; accepted 22 November 2010; online 27 November 2010)

The title compound, C13H11N3O, a potential chemotherapeutic agent, contains a essential planar [maximum deviation = 0.0144 (14) Å] quinoline moiety. The quinoline ring system and the five-membered heterocycle form a dihedral angle of 7.81 (6)°. In the crystal, inter­molecular non-classical C—H⋯N hydrogen bonding is present.

Related literature

For general background to the use of compounds containing a quinoline fragment as chemotherapeutical agents, see: Kaila et al. (2007[Kaila, N., Janz, K., Huang, A., Moretto, A., DeBernardo, S., Bedard, P. W., Tam, S., Clerin, V., Keith, J. C., Tsao, H. H., Sushkova, N., Shaw, G. D., Camphausen, R. T. G., Schaub, R. G. & Qin Wang, Q. (2007). J. Med. Chem. 50, 40-64.]); Vaitilingam et al. (2004[Vaitilingam, B., Nayyar, A., Palde, P. B., Monga, V., Jain, R., Kaur, S. & Singh, P. P. (2004). Bioorg. Med. Chem. 12, 4179-4188.]).

[Scheme 1]

Experimental

Crystal data

  • C13H11N3O

  • Mr = 225.25

  • Monoclinic, P 21 /c

  • a = 15.5372 (14) Å

  • b = 9.7546 (7) Å

  • c = 7.3984 (5) Å

  • β = 100.64 (1)°

  • V = 1102.02 (15) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 0.73 mm−1

  • T = 295 K

  • 0.20 × 0.20 × 0.20 mm
Data collection

  • Enraf–Nonius CAD-4 diffractometer

  • Absorption correction: refined from ΔF (Walker & Stuart, 1983[Walker, N. & Stuart, D. (1983). Acta Cryst. A39, 158-166.]) Tmin = 0.391, Tmax = 0.865

  • 2236 measured reflections

  • 2236 independent reflections

  • 1855 reflections with I > 2σ(I)

  • 1 standard reflections every 60 min intensity decay: 1%
Refinement

  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.130

  • S = 1.07

  • 2236 reflections

  • 156 parameters

  • H-atom parameters constrained

  • Δρmax = 0.18 e Å−3

  • Δρmin = −0.14 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C13—H13⋯N15i 0.93 2.59 3.523 (2) 178
Symmetry code: (i) [-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994[Enraf-Nonius (1994). CAD-4 EXPRESS. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995[Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810048683/ds2065sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810048683/ds2065Isup2.hkl

checkCIF report


Comment top

The compounds containing a fragment of quinoline ring, are widely used as chemotherapeutical agents (Vaitilingam et al., 2004; Kaila et al., 2007). Synthesis of new quinoline derivatives and study of its properties to be of interest in theoretic and practical aspects as well. The 2,6-dimethyl-4-(1,3,4-oxadiazol-2-yl)quinoline II was synthesized from triethyl orthoformate and hydrazide 2,6-dimethyl-4-quinoline carboxylic acid I (Fig. 1).

In the crystal structure is found non-classical intermolecular hydrogen bond - C13–H13···N15i, where contacts H13···N15i = 2.594 Å, C13···N15i = 3.523 (2)Å and angle C13–H13···N15i = 178°. Symmetry code:(i) -x, y + 1/2, -z + 1/2. The short intramolecular contacts C6–H6···N15 (H6···N15 = 2.370 Å) and C3–H3···O12 (H3···O12 = 2.372 Å) are obliged by conjugation of oxadiazol and guinoline moieties - in title molecule, guinoline moiety is planar (max deviation of C7 = 0.0144 (14) Å) and essential planar oxadiazol moiety form dihedral angle 7.81 (6)° (Fig. 2).

Related literature top

For general background to the use of compounds containing a quinoline fragment as chemotherapeutical agents, see: Kaila et al. (2007); Vaitilingam et al. (2004).

Experimental top

A solution of triethyl orthoformate (60 mmol) and 2,6-dimethyl-4-(1,3,4-oxadiazol-2-yl)quinoline (5 mmol) was refluxed for 20 h. Ester was removed in a vacuum. Recrystallization of the crude product from ethanol gave 0.89 g of colourless crystals. Yield 79%, mp 448-449 K.

IR, ν, cm-1: 3116 (C–H, oxadiazol), 1751 (CO), 1600 (C═C), 1508 (C═ N). MS, m/z: 225 (100) [M]+, 210 (17), 184 (11), 156 (32), 115 (15), 89 (8), 63 (9). 1H NMR, δ: 2.51 s (3H, 6-CH3), 2.71 s (3H, 2-CH3), 7.63 d (1H, J = 8.80, 7-H), 7.89 s (1H, 3-H), 7.92 d (1H, J = 8.80, 8-H), 8.71 s (1H, 5-H), 9.52 s (1H, C–H oxadiazol). Anal. calc. for C13H11N3O, %: C 69.32; H 4.92; N 18.66. Found, %: C 69.27; H 4.83; N 18.61.

Single crystals for X-ray analysis were obtained by slow evaporation of an ethanol. IR spectrum was recorded (in KBr) on Shimadzu FTIR-8400S. Mass spectrum was measured on Finnigan Trance DSQ spectrometer. 1H NMR spectrum was obtained in DMSO-d6 on Bruker AM 300 (300 MHz), using TMS as internal standard. Elemental composition was determined on Euro Vector EA-3000 elemental analyzer.

Refinement top

C-bound H-atoms were placed in calculated positions (C–H 0.93 Å & 0.97 Å) and refined as riding, with Uiso(H) = 1.2Ueq(C).

Structure description top

The compounds containing a fragment of quinoline ring, are widely used as chemotherapeutical agents (Vaitilingam et al., 2004; Kaila et al., 2007). Synthesis of new quinoline derivatives and study of its properties to be of interest in theoretic and practical aspects as well. The 2,6-dimethyl-4-(1,3,4-oxadiazol-2-yl)quinoline II was synthesized from triethyl orthoformate and hydrazide 2,6-dimethyl-4-quinoline carboxylic acid I (Fig. 1).

In the crystal structure is found non-classical intermolecular hydrogen bond - C13–H13···N15i, where contacts H13···N15i = 2.594 Å, C13···N15i = 3.523 (2)Å and angle C13–H13···N15i = 178°. Symmetry code:(i) -x, y + 1/2, -z + 1/2. The short intramolecular contacts C6–H6···N15 (H6···N15 = 2.370 Å) and C3–H3···O12 (H3···O12 = 2.372 Å) are obliged by conjugation of oxadiazol and guinoline moieties - in title molecule, guinoline moiety is planar (max deviation of C7 = 0.0144 (14) Å) and essential planar oxadiazol moiety form dihedral angle 7.81 (6)° (Fig. 2).

For general background to the use of compounds containing a quinoline fragment as chemotherapeutical agents, see: Kaila et al. (2007); Vaitilingam et al. (2004).

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. Synthesis of the title compound.
[Figure 2] Fig. 2. ORTEP-3 (Farrugia, 1997) plot of molecular structure of the title compound showing the atom-numbering scheme. Thermal displacement ellipsoids are drawn at the 50% probability level. H atoms are presented as a small spheres of arbitrary radius.
2,6-Dimethyl-4-(1,3,4-oxadiazol-2-yl)quinoline top
Crystal data top
C13H11N3OF(000) = 472
Mr = 225.25Dx = 1.358 Mg m−3
Monoclinic, P21/cMelting point = 448–449 K
Hall symbol: -P 2ybcCu Kα radiation, λ = 1.54184 Å
a = 15.5372 (14) ÅCell parameters from 25 reflections
b = 9.7546 (7) Åθ = 36.3–39.9°
c = 7.3984 (5) ŵ = 0.73 mm−1
β = 100.64 (1)°T = 295 K
V = 1102.02 (15) Å3Prism, colourless
Z = 40.20 × 0.20 × 0.20 mm
Data collection top
Enraf–Nonius CAD-4
diffractometer		1855 reflections with I > 2σ(I)
Radiation source: Fine-focus sealed tubeRint = 0.000
Graphite monochromatorθmax = 74.9°, θmin = 2.9°
Non–profiled ω scansh = 0→19
Absorption correction: part of the refinement model (ΔF)
(Walker & Stuart, 1983)		k = 0→12
Tmin = 0.391, Tmax = 0.865l = −8→9
2236 measured reflections1 standard reflections every 60 min
2236 independent reflections intensity decay: 1%
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)] = 0.042Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.130H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0669P)2 + 0.1662P]
where P = (Fo2 + 2Fc2)/3
2236 reflections(Δ/σ)max = 0.005
156 parametersΔρmax = 0.18 e Å−3
0 restraintsΔρmin = −0.14 e Å−3
Crystal data top
C13H11N3OV = 1102.02 (15) Å3
Mr = 225.25Z = 4
Monoclinic, P21/cCu Kα radiation
a = 15.5372 (14) ŵ = 0.73 mm−1
b = 9.7546 (7) ÅT = 295 K
c = 7.3984 (5) Å0.20 × 0.20 × 0.20 mm
β = 100.64 (1)°
Data collection top
Enraf–Nonius CAD-4
diffractometer		1855 reflections with I > 2σ(I)
Absorption correction: part of the refinement model (ΔF)
(Walker & Stuart, 1983)		Rint = 0.000
Tmin = 0.391, Tmax = 0.8651 standard reflections every 60 min
2236 measured reflections intensity decay: 1%
2236 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0420 restraints
wR(F2) = 0.130H-atom parameters constrained
S = 1.07Δρmax = 0.18 e Å−3
2236 reflectionsΔρmin = −0.14 e Å−3
156 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
N10.39891 (8)0.63577 (13)0.05252 (18)0.0557 (3)
C20.36926 (10)0.75870 (16)0.0823 (2)0.0549 (4)
C210.42870 (12)0.87852 (19)0.0735 (3)0.0720 (5)
H21A0.48750.84640.07810.108*
H21B0.42710.93830.17580.108*
H21C0.40960.9276−0.03930.108*
C30.28466 (10)0.77894 (16)0.1206 (2)0.0537 (4)
H30.26630.86730.14170.064*
C40.22912 (9)0.67122 (14)0.12717 (19)0.0479 (3)
C50.25819 (9)0.53629 (15)0.09414 (18)0.0468 (3)
C60.20838 (9)0.41454 (15)0.09503 (19)0.0505 (3)
H60.15130.42060.11580.061*
C70.24197 (10)0.28864 (15)0.0662 (2)0.0532 (4)
C710.19028 (12)0.15983 (16)0.0748 (3)0.0656 (4)
H71A0.13150.18290.08680.098*
H71B0.21710.10620.17890.098*
H71C0.18910.1078−0.03580.098*
C80.32817 (11)0.28112 (16)0.0302 (2)0.0599 (4)
H80.35150.19590.00970.072*
C90.37777 (10)0.39518 (17)0.0249 (2)0.0587 (4)
H90.43400.3871−0.00030.070*
C100.34470 (9)0.52589 (15)0.0574 (2)0.0508 (3)
C110.14273 (9)0.69987 (15)0.1721 (2)0.0500 (3)
O120.11965 (7)0.83379 (11)0.18110 (16)0.0631 (3)
C130.03932 (11)0.8249 (2)0.2255 (3)0.0688 (5)
H130.00570.90130.24190.083*
N140.01403 (9)0.70333 (17)0.2429 (2)0.0739 (4)
N150.08253 (9)0.61910 (15)0.2072 (2)0.0651 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0469 (6)0.0603 (8)0.0626 (8)−0.0012 (5)0.0168 (5)0.0026 (6)
C20.0506 (8)0.0585 (9)0.0568 (8)−0.0052 (6)0.0135 (6)0.0015 (6)
C210.0661 (10)0.0651 (10)0.0887 (13)−0.0142 (8)0.0241 (9)0.0008 (9)
C30.0542 (8)0.0518 (8)0.0570 (9)0.0007 (6)0.0150 (6)−0.0010 (6)
C40.0464 (7)0.0516 (8)0.0468 (8)0.0019 (6)0.0117 (6)0.0008 (6)
C50.0456 (7)0.0520 (8)0.0442 (7)0.0029 (6)0.0119 (5)0.0018 (5)
C60.0472 (7)0.0558 (8)0.0508 (8)0.0007 (6)0.0150 (6)0.0008 (6)
C70.0561 (8)0.0517 (8)0.0532 (8)0.0012 (6)0.0134 (6)0.0002 (6)
C710.0701 (10)0.0550 (9)0.0745 (11)−0.0045 (8)0.0207 (8)−0.0047 (7)
C80.0602 (9)0.0530 (8)0.0695 (10)0.0098 (7)0.0195 (7)0.0008 (7)
C90.0491 (8)0.0616 (9)0.0693 (10)0.0082 (7)0.0209 (7)0.0009 (7)
C100.0463 (7)0.0557 (8)0.0522 (8)0.0019 (6)0.0142 (6)0.0033 (6)
C110.0501 (7)0.0510 (8)0.0506 (8)0.0051 (6)0.0138 (6)−0.0015 (6)
O120.0570 (6)0.0550 (6)0.0804 (8)0.0078 (5)0.0207 (5)−0.0039 (5)
C130.0575 (9)0.0735 (11)0.0795 (12)0.0173 (8)0.0235 (8)−0.0056 (9)
N140.0573 (8)0.0778 (10)0.0940 (11)0.0120 (7)0.0337 (7)0.0009 (8)
N150.0538 (7)0.0647 (8)0.0840 (10)0.0053 (6)0.0315 (7)0.0014 (7)
Geometric parameters (Å, º) top
N1—C21.3177 (19)C7—C81.415 (2)
N1—C101.3677 (18)C7—C711.499 (2)
C2—C31.408 (2)C71—H71A0.9600
C2—C211.499 (2)C71—H71B0.9600
C21—H21A0.9600C71—H71C0.9600
C21—H21B0.9600C8—C91.358 (2)
C21—H21C0.9600C8—H80.9300
C3—C41.366 (2)C9—C101.412 (2)
C3—H30.9300C9—H90.9300
C4—C51.4271 (19)C11—N151.286 (2)
C4—C111.4680 (19)C11—O121.3596 (17)
C5—C61.4182 (19)O12—C131.3508 (19)
C5—C101.4233 (19)C13—N141.263 (2)
C6—C71.366 (2)C13—H130.9300
C6—H60.9300N14—N151.4075 (18)
C2—N1—C10118.21 (12)C7—C71—H71A109.5
N1—C2—C3121.95 (14)C7—C71—H71B109.5
N1—C2—C21117.71 (14)H71A—C71—H71B109.5
C3—C2—C21120.33 (14)C7—C71—H71C109.5
C2—C21—H21A109.5H71A—C71—H71C109.5
C2—C21—H21B109.5H71B—C71—H71C109.5
H21A—C21—H21B109.5C9—C8—C7121.66 (14)
C2—C21—H21C109.5C9—C8—H8119.2
H21A—C21—H21C109.5C7—C8—H8119.2
H21B—C21—H21C109.5C8—C9—C10120.58 (13)
C4—C3—C2121.23 (14)C8—C9—H9119.7
C4—C3—H3119.4C10—C9—H9119.7
C2—C3—H3119.4N1—C10—C9117.26 (13)
C3—C4—C5118.75 (13)N1—C10—C5123.86 (13)
C3—C4—C11118.15 (13)C9—C10—C5118.88 (13)
C5—C4—C11123.09 (12)N15—C11—O12111.76 (13)
C6—C5—C10118.46 (13)N15—C11—C4131.21 (14)
C6—C5—C4125.54 (12)O12—C11—C4117.03 (12)
C10—C5—C4116.00 (13)C13—O12—C11102.38 (12)
C7—C6—C5121.84 (13)N14—C13—O12113.79 (14)
C7—C6—H6119.1N14—C13—H13123.1
C5—C6—H6119.1O12—C13—H13123.1
C6—C7—C8118.56 (14)C13—N14—N15105.60 (13)
C6—C7—C71121.59 (13)C11—N15—N14106.47 (14)
C8—C7—C71119.84 (14)
C10—N1—C2—C30.7 (2)C2—N1—C10—C5−0.4 (2)
C10—N1—C2—C21−178.99 (14)C8—C9—C10—N1179.04 (14)
N1—C2—C3—C4−0.4 (2)C8—C9—C10—C5−0.6 (2)
C21—C2—C3—C4179.24 (15)C6—C5—C10—N1179.88 (13)
C2—C3—C4—C5−0.1 (2)C4—C5—C10—N1−0.1 (2)
C2—C3—C4—C11178.58 (13)C6—C5—C10—C9−0.5 (2)
C3—C4—C5—C6−179.61 (13)C4—C5—C10—C9179.53 (13)
C11—C4—C5—C61.8 (2)C3—C4—C11—N15−171.28 (16)
C3—C4—C5—C100.3 (2)C5—C4—C11—N157.4 (3)
C11—C4—C5—C10−178.28 (13)C3—C4—C11—O128.1 (2)
C10—C5—C6—C71.6 (2)C5—C4—C11—O12−173.22 (12)
C4—C5—C6—C7−178.43 (14)N15—C11—O12—C130.07 (17)
C5—C6—C7—C8−1.6 (2)C4—C11—O12—C13−179.46 (13)
C5—C6—C7—C71177.53 (14)C11—O12—C13—N140.0 (2)
C6—C7—C8—C90.4 (2)O12—C13—N14—N15−0.1 (2)
C71—C7—C8—C9−178.70 (15)O12—C11—N15—N14−0.13 (18)
C7—C8—C9—C100.7 (3)C4—C11—N15—N14179.32 (15)
C2—N1—C10—C9179.94 (13)C13—N14—N15—C110.14 (19)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13···N15i0.932.593.523 (2)178
Symmetry code: (i) −x, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formulaC13H11N3O
Mr225.25
Crystal system, space groupMonoclinic, P21/c
Temperature (K)295
a, b, c (Å)15.5372 (14), 9.7546 (7), 7.3984 (5)
β (°) 100.64 (1)
V (Å3)1102.02 (15)
Z4
Radiation typeCu Kα
µ (mm−1)0.73
Crystal size (mm)0.20 × 0.20 × 0.20
Data collection
DiffractometerEnraf–Nonius CAD-4
Absorption correctionPart of the refinement model (ΔF)
(Walker & Stuart, 1983)
Tmin, Tmax0.391, 0.865
No. of measured, independent and
observed [I > 2σ(I)] reflections		2236, 2236, 1855
Rint0.000
(sin θ/λ)max (Å−1)0.626
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.130, 1.07
No. of reflections2236
No. of parameters156
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.18, −0.14

Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13···N15i0.932.5943.523 (2)178
Symmetry code: (i) −x, y+1/2, −z+1/2.
 

Acknowledgements

The authors are indebted to Russian Foundation for Basic Research for covering the licence fee for use of the Cambridge Structural Database (Allen, 2002[Allen, F. H. (2002). Acta Cryst. B58, 380-388.]).

References

First citationAllen, F. H. (2002). Acta Cryst. B58, 380–388.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
 First citationEnraf–Nonius (1994). CAD-4 EXPRESS. Enraf–Nonius, Delft, The Netherlands.  Google Scholar
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ISSN: 2056-9890
Volume 66| Part 12| December 2010| Page o3333
https://doi.org/10.1107/S1600536810048683
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