6-Chloro-2-cyclo­propyl-4-(trifluoro­meth­yl)quinoline

Devarajegowda, H.C.; Arunkashi, H.K.; Vepuri, S.B.; Chidananda, N.; Prasad, V.D.J.

doi:10.1107/S1600536811003746

organic compounds

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ISSN: 2056-9890

Volume 67| Part 3| March 2011| Page o564

doi:10.1107/S1600536811003746

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6-Chloro-2-cyclopropyl-4-(trifluoromethyl)quinoline

H. C. Devarajegowda,^a ^* H. K. Arunkashi,^a Suresh Babu Vepuri,^b N. Chidananda ^c and V. D. Jagadeesh Prasad ^c

^aDepartment of Physics, Yuvaraja's College (Constituent College), University of Mysore, Mysore 570 005, Karnataka, India, ^bDepartment of Pharmaceutical Chemistry, GITAM Institute of Pharmacy, GITAM University, Visakhapatnam 530 045, Andhrapradesh, India, and ^cDepartment of Chemistry, Mangalore University, Mangalagangotri 574 199, Karnataka, India
^*Correspondence e-mail: devarajegowda@yahoo.com

(Received 27 January 2011; accepted 29 January 2011; online 5 February 2011)

In the title compound, C₁₃H₉ClF₃N, the quinoline ring system makes a dihedral angle of 88.8 (2)° with the cyclopropyl ring.

Related literature

For general background to quinolines see: Kayser & Novak (1987 ); Rudin et al. (1984 ); Mao et al. (2009 ); Bermudez et al. (2004 ); Jayaprakash et al. (2006 ); Andries et al. (2005 ). For related structures, see: Skörska et al. (2005 ); Devarajegowda et al. (2010 ); Li et al. (2005 ).

Experimental

Crystal data

C₁₃H₉ClF₃N
M_r = 271.66
Monoclinic, P 2₁ /c
a = 13.8482 (19) Å
b = 5.0534 (8) Å
c = 18.048 (3) Å
β = 107.503 (17)°
V = 1204.5 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.33 mm⁻¹
T = 293 K
0.22 × 0.15 × 0.12 mm

Data collection

Oxford Diffraction Xcalibur diffractometer
Absorption correction: multi-scan (CrysAlis PRO RED; Oxford Diffraction, 2010 $[Oxford Diffraction (2010). CrysAlis PRO CCD and CrysAlis PRO RED. Oxford Diffraction Ltd, Yarnton, England.]$ ) T_min = 0.942, T_max = 0.961
11631 measured reflections
2105 independent reflections
946 reflections with I > 2σ(I)
R_int = 0.092

Refinement

R[F² > 2σ(F²)] = 0.041
wR(F²) = 0.081
S = 0.78
2105 reflections
164 parameters
H-atom parameters constrained
Δρ_max = 0.13 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Data collection: CrysAlis PRO CCD (Oxford Diffraction, 2010 $[Oxford Diffraction (2010). CrysAlis PRO CCD and CrysAlis PRO RED. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis PRO CCD; data reduction: CrysAlis PRO RED (Oxford Diffraction, 2010 $[Oxford Diffraction (2010). CrysAlis PRO CCD and CrysAlis PRO RED. Oxford Diffraction Ltd, Yarnton, England.]$ ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ) and CAMERON (Watkin et al., 1993); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811003746/wn2420sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811003746/wn2420Isup2.hkl

checkCIF report

Comment top

1-Cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)- 3-quinolinecarboxylic acid (ciprofloxacin) is a widely used broad-spectrum antibiotic, which is active against both Gram-positive and Gram-negative bacteria (Kayser & Novak, 1987; Rudin et al., 1984). 2,8-Bis(trifluoromethyl)quinolin-4-yl]-(2-piperidyl)methanol (mefloquin) is another popular quinoline derivative used in the treatment of malaria. Furthermore, studies have reported that it also possesses important structural features required for antimicrobial activity (Mao et al., 2009; Bermudez et al., 2004; Jayaprakash et al., 2006). Quinoline is the essential structural feature found in these drugs and recently developed antimycobacterial drugs (Andries et al., 2005). Thus, quinoline derivatives are good lead molecules to further develop drug candidates against mycobacterium tuberculosis and as antibacterial agents. On the basis of these observations, we have synthesized a quinoline derivative, with a cyclopropyl group and a trifluoromethyl group as substituents, expecting that the newly designed hybrid molecule would exhibit some antibacterial activity. In this paper we report the crystal structure of 6-chloro-2-cyclopropyl-4-(trifluoromethyl)quinoline.

The asymmetric unit of the 6-chloro-2-cyclopropyl-4-(trifluoromethyl) quinoline contains one molecule (Fig. 1). The quinoline ring system makes a dihedral angle of 88.8 (2)° with the cyclopropyl ring. Bond distances and bond angles in the quinoline ring system are in good agreement with those observed in related crystal structures (Skörska et al., 2005; Devarajegowda et al., 2010; Li et al., 2005). The packing of the molecules, when viewed along the b axis, is shown in Fig. 2.

Related literature top

For general background to quinolines see: Kayser & Novak (1987); Rudin et al. (1984); Mao et al. (2009); Bermudez et al. (2004); Jayaprakash et al. (2006); Andries et al. (2005). For related structures, see: Skörska et al. (2005); Devarajegowda et al. (2010); Li et al. (2005).

Experimental top

A mixture of cyclopropyl acetylene (0.012 mol), anhydrous zinc(II) (0.012 mol), triethylamine (1.67 ml, 0.012 mol), and toluene (25 ml) was stirred at 50°C for 2 h and cooled to 25°C. 4-Chloro- 2-trifluoroacetylaniline (0.01 mol) was added and the reaction mixture was stirred at 25°C for 4 h, then at 50°C for 4 h. After cooling to room temperature, the mixture was added to water (10 ml) and extracted three times with ethyl acetate (20 ml). The combined organic phase was washed with brine and dried over anhydrous sodium sulfate. After removal of solvent, the residue was purified by column chromatography on silica gel (hexane/ethyl acetate; 20:1). M.p. 335 K.

Computing details top

Data collection: CrysAlis PRO CCD (Oxford Diffraction, 2010); cell refinement: CrysAlis PRO CCD (Oxford Diffraction, 2010); data reduction: CrysAlis PRO RED (Oxford Diffraction, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and CAMERON (Watkin et al., 1993); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen atoms are shown as spheres of arbitrary radius.
	Fig. 2. The packing of molecules, viewed down the b axis.

6-Chloro-2-cyclopropyl-4-(trifluoromethyl)quinoline top

Crystal data top

C₁₃H₉ClF₃N	F(000) = 552
M_r = 271.66	D_x = 1.498 Mg m⁻³
Monoclinic, P2₁/c	Melting point: 335 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 13.8482 (19) Å	Cell parameters from 2105 reflections
b = 5.0534 (8) Å	θ = 2.4–25.0°
c = 18.048 (3) Å	µ = 0.33 mm⁻¹
β = 107.503 (17)°	T = 293 K
V = 1204.5 (3) Å³	Plate, colourless
Z = 4	0.22 × 0.15 × 0.12 mm

Data collection top

Oxford Diffraction Xcalibur diffractometer	2105 independent reflections
Radiation source: Enhance (Mo) X-ray Source	946 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.092
Detector resolution: 16.0839 pixels mm^-1	θ_max = 25.0°, θ_min = 2.4°
ω scans	h = −16→16
Absorption correction: multi-scan (CrysAlis PRO RED; Oxford Diffraction, 2010)	k = −6→6
T_min = 0.942, T_max = 0.961	l = −21→21
11631 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.041	H-atom parameters constrained
wR(F²) = 0.081	w = 1/[σ²(F_o²) + (0.0334P)²] where P = (F_o² + 2F_c²)/3
S = 0.78	(Δ/σ)_max = 0.004
2105 reflections	Δρ_max = 0.13 e Å⁻³
164 parameters	Δρ_min = −0.17 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0045 (8)

Crystal data top

C₁₃H₉ClF₃N	V = 1204.5 (3) Å³
M_r = 271.66	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 13.8482 (19) Å	µ = 0.33 mm⁻¹
b = 5.0534 (8) Å	T = 293 K
c = 18.048 (3) Å	0.22 × 0.15 × 0.12 mm
β = 107.503 (17)°

Data collection top

Oxford Diffraction Xcalibur diffractometer	2105 independent reflections
Absorption correction: multi-scan (CrysAlis PRO RED; Oxford Diffraction, 2010)	946 reflections with I > 2σ(I)
T_min = 0.942, T_max = 0.961	R_int = 0.092
11631 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.041	0 restraints
wR(F²) = 0.081	H-atom parameters constrained
S = 0.78	Δρ_max = 0.13 e Å⁻³
2105 reflections	Δρ_min = −0.17 e Å⁻³
164 parameters

Special details top

Experimental. CrysAlis PRO, Oxford Diffraction Ltd., Version 1.171.33.55 (release 05–01–2010 CrysAlis171. NET) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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

	x	y	z	U_iso*/U_eq
Cl1	0.24504 (7)	−0.53695 (16)	0.14138 (5)	0.0724 (3)
F1	0.53230 (12)	0.2294 (4)	0.43406 (12)	0.1017 (8)
F2	0.49335 (13)	0.1618 (4)	0.31203 (13)	0.0964 (7)
F3	0.49773 (12)	−0.1595 (4)	0.38888 (11)	0.0896 (7)
N9	0.15811 (17)	0.2481 (4)	0.35357 (14)	0.0463 (6)
C1	0.1215 (2)	0.4767 (6)	0.49521 (17)	0.0629 (9)
H1A	0.0846	0.3137	0.4779	0.076*
H1B	0.1300	0.5228	0.5490	0.076*
C2	0.2051 (2)	0.5449 (6)	0.46255 (18)	0.0612 (9)
H2	0.2623	0.6398	0.4980	0.073*
C3	0.1078 (2)	0.6908 (6)	0.43962 (19)	0.0695 (10)
H3A	0.1077	0.8701	0.4588	0.083*
H3B	0.0624	0.6610	0.3878	0.083*
C4	0.2319 (2)	0.3623 (5)	0.40752 (17)	0.0486 (8)
C5	0.3343 (2)	0.3113 (6)	0.41542 (17)	0.0542 (9)
H5	0.3843	0.3978	0.4540	0.065*
C6	0.3612 (2)	0.1390 (6)	0.36802 (17)	0.0463 (8)
C7	0.2855 (2)	0.0029 (5)	0.30968 (16)	0.0401 (7)
C8	0.1844 (2)	0.0691 (5)	0.30551 (16)	0.0405 (7)
C10	0.4703 (3)	0.0937 (8)	0.3759 (2)	0.0678 (10)
C11	0.3025 (2)	−0.1850 (5)	0.25749 (16)	0.0452 (8)
H11	0.3683	−0.2290	0.2591	0.054*
C12	0.2229 (2)	−0.3017 (5)	0.20490 (16)	0.0456 (8)
C13	0.1232 (2)	−0.2394 (6)	0.19959 (16)	0.0489 (8)
H13	0.0699	−0.3229	0.1630	0.059*
C14	0.1044 (2)	−0.0553 (6)	0.24840 (16)	0.0464 (8)
H14	0.0378	−0.0105	0.2442	0.056*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0857 (7)	0.0722 (6)	0.0640 (6)	−0.0003 (5)	0.0296 (5)	−0.0188 (5)
F1	0.0448 (12)	0.1346 (18)	0.1136 (18)	−0.0181 (12)	0.0057 (12)	−0.0505 (15)
F2	0.0542 (13)	0.148 (2)	0.1014 (19)	−0.0123 (12)	0.0445 (12)	0.0029 (14)
F3	0.0516 (12)	0.0939 (15)	0.1143 (18)	0.0143 (11)	0.0113 (11)	−0.0095 (13)
N9	0.0436 (15)	0.0528 (16)	0.0448 (16)	−0.0020 (14)	0.0165 (13)	−0.0026 (14)
C1	0.085 (3)	0.058 (2)	0.057 (2)	0.0067 (19)	0.0374 (19)	−0.0017 (19)
C2	0.049 (2)	0.071 (2)	0.066 (2)	−0.0092 (19)	0.0205 (19)	−0.024 (2)
C3	0.095 (3)	0.051 (2)	0.068 (3)	0.011 (2)	0.032 (2)	0.0001 (19)
C4	0.044 (2)	0.055 (2)	0.051 (2)	−0.0035 (17)	0.0208 (18)	−0.0058 (17)
C5	0.044 (2)	0.063 (2)	0.054 (2)	−0.0126 (17)	0.0135 (17)	−0.0157 (17)
C6	0.037 (2)	0.055 (2)	0.049 (2)	0.0002 (16)	0.0153 (17)	−0.0012 (16)
C7	0.036 (2)	0.0463 (19)	0.0404 (18)	−0.0017 (15)	0.0158 (15)	0.0033 (16)
C8	0.044 (2)	0.0452 (18)	0.0351 (18)	−0.0051 (16)	0.0169 (16)	0.0028 (15)
C10	0.051 (3)	0.078 (3)	0.077 (3)	−0.003 (2)	0.023 (2)	−0.013 (2)
C11	0.0381 (19)	0.0523 (19)	0.049 (2)	0.0010 (16)	0.0191 (17)	0.0017 (17)
C12	0.053 (2)	0.0478 (19)	0.0413 (19)	−0.0054 (17)	0.0221 (17)	−0.0045 (15)
C13	0.045 (2)	0.055 (2)	0.046 (2)	−0.0110 (17)	0.0128 (17)	−0.0012 (17)
C14	0.0364 (18)	0.056 (2)	0.048 (2)	−0.0007 (16)	0.0144 (17)	−0.0033 (17)

Geometric parameters (Å, º) top

Cl1—C12	1.741 (3)	C4—C5	1.406 (4)
F1—C10	1.329 (3)	C5—C6	1.349 (3)
F2—C10	1.330 (4)	C5—H5	0.9300
F3—C10	1.335 (3)	C6—C7	1.420 (3)
N9—C4	1.314 (3)	C6—C10	1.492 (4)
N9—C8	1.376 (3)	C7—C11	1.406 (3)
C1—C3	1.449 (4)	C7—C8	1.419 (3)
C1—C2	1.490 (4)	C8—C14	1.413 (3)
C1—H1A	0.9700	C11—C12	1.354 (3)
C1—H1B	0.9700	C11—H11	0.9300
C2—C3	1.481 (4)	C12—C13	1.392 (3)
C2—C4	1.482 (4)	C13—C14	1.359 (3)
C2—H2	0.9800	C13—H13	0.9300
C3—H3A	0.9700	C14—H14	0.9300
C3—H3B	0.9700

C4—N9—C8	117.5 (3)	C5—C6—C10	120.2 (3)
C3—C1—C2	60.5 (2)	C7—C6—C10	119.8 (3)
C3—C1—H1A	117.7	C11—C7—C8	119.0 (3)
C2—C1—H1A	117.7	C11—C7—C6	126.1 (3)
C3—C1—H1B	117.7	C8—C7—C6	114.9 (3)
C2—C1—H1B	117.7	N9—C8—C14	117.0 (3)
H1A—C1—H1B	114.8	N9—C8—C7	124.4 (3)
C3—C2—C4	120.8 (3)	C14—C8—C7	118.6 (3)
C3—C2—C1	58.35 (19)	F1—C10—F2	106.5 (3)
C4—C2—C1	120.1 (3)	F1—C10—F3	105.9 (3)
C3—C2—H2	115.3	F2—C10—F3	105.7 (3)
C4—C2—H2	115.3	F1—C10—C6	113.0 (3)
C1—C2—H2	115.3	F2—C10—C6	112.2 (3)
C1—C3—C2	61.12 (19)	F3—C10—C6	113.0 (3)
C1—C3—H3A	117.7	C12—C11—C7	119.9 (3)
C2—C3—H3A	117.7	C12—C11—H11	120.0
C1—C3—H3B	117.7	C7—C11—H11	120.0
C2—C3—H3B	117.7	C11—C12—C13	122.1 (3)
H3A—C3—H3B	114.8	C11—C12—Cl1	119.5 (2)
N9—C4—C5	122.0 (3)	C13—C12—Cl1	118.5 (2)
N9—C4—C2	118.4 (3)	C14—C13—C12	119.3 (3)
C5—C4—C2	119.6 (3)	C14—C13—H13	120.3
C6—C5—C4	121.1 (3)	C12—C13—H13	120.3
C6—C5—H5	119.4	C13—C14—C8	121.1 (3)
C4—C5—H5	119.4	C13—C14—H14	119.5
C5—C6—C7	120.0 (3)	C8—C14—H14	119.5

C3—C1—C2—C4	−109.7 (3)	C6—C7—C8—N9	−0.6 (4)
C4—C2—C3—C1	108.6 (3)	C11—C7—C8—C14	−0.5 (4)
C8—N9—C4—C5	1.6 (4)	C6—C7—C8—C14	179.3 (2)
C8—N9—C4—C2	−176.8 (2)	C5—C6—C10—F1	2.5 (5)
C3—C2—C4—N9	−27.5 (4)	C7—C6—C10—F1	−178.5 (3)
C1—C2—C4—N9	41.4 (4)	C5—C6—C10—F2	−118.0 (3)
C3—C2—C4—C5	154.1 (3)	C7—C6—C10—F2	61.0 (4)
C1—C2—C4—C5	−137.1 (3)	C5—C6—C10—F3	122.6 (3)
N9—C4—C5—C6	−0.8 (5)	C7—C6—C10—F3	−58.3 (4)
C2—C4—C5—C6	177.6 (3)	C8—C7—C11—C12	−0.7 (4)
C4—C5—C6—C7	−0.9 (4)	C6—C7—C11—C12	179.5 (3)
C4—C5—C6—C10	178.2 (3)	C7—C11—C12—C13	0.9 (4)
C5—C6—C7—C11	−178.7 (3)	C7—C11—C12—Cl1	−179.23 (19)
C10—C6—C7—C11	2.2 (4)	C11—C12—C13—C14	0.2 (4)
C5—C6—C7—C8	1.5 (4)	Cl1—C12—C13—C14	−179.7 (2)
C10—C6—C7—C8	−177.6 (3)	C12—C13—C14—C8	−1.5 (4)
C4—N9—C8—C14	179.1 (2)	N9—C8—C14—C13	−178.4 (2)
C4—N9—C8—C7	−0.9 (4)	C7—C8—C14—C13	1.6 (4)
C11—C7—C8—N9	179.5 (2)

Experimental details

Crystal data
Chemical formula	C₁₃H₉ClF₃N
M_r	271.66
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	13.8482 (19), 5.0534 (8), 18.048 (3)
β (°)	107.503 (17)
V (Å³)	1204.5 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.33
Crystal size (mm)	0.22 × 0.15 × 0.12

Data collection
Diffractometer	Oxford Diffraction Xcalibur diffractometer
Absorption correction	Multi-scan (CrysAlis PRO RED; Oxford Diffraction, 2010)
T_min, T_max	0.942, 0.961
No. of measured, independent and observed [I > 2σ(I)] reflections	11631, 2105, 946
R_int	0.092
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.041, 0.081, 0.78
No. of reflections	2105
No. of parameters	164
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.13, −0.17

Computer programs: CrysAlis PRO CCD (Oxford Diffraction, 2010), CrysAlis PRO RED (Oxford Diffraction, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and CAMERON (Watkin et al., 1993), WinGX (Farrugia, 1999).

Acknowledgements

The authors thank Professor T. N. Guru Row and Mr Venkatesha R. Hathwar, Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore, for their help with the data collection.

References

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