Ethyl 1-(4-chloro­benz­yl)-3-(4-fluoro­phen­yl)-1H-pyrazole-5-carboxyl­ate

Ge, Y.Q.; Zhang, J.M.; Wang, G.L.; Xu, H.; Shi, B.

doi:10.1107/S1600536811017156

organic compounds

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ISSN: 2056-9890

Volume 67| Part 6| June 2011| Page o1387

doi:10.1107/S1600536811017156

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Ethyl 1-(4-chlorobenzyl)-3-(4-fluorophenyl)-1H-pyrazole-5-carboxylate

Yan Qing Ge,^a ^* Ji Mei Zhang,^a Guang Liang Wang,^a Hao Xu ^a and Bo Shi ^a

^aTaishan Medical College, Tai an, 271016, People's Republic of China
^*Correspondence e-mail: yqge@yahoo.cn

(Received 20 April 2011; accepted 6 May 2011; online 11 May 2011)

In the title compound, C₁₉H₁₆ClFN₂O₂, the pyrazole ring makes dihedral angles of 5.15 (6) and 77.72 (6)°, with the fluorophenyl and chlorophenyl rings, respectively.

Related literature

For the pharmacological activity of pyrazole compounds, see: Ge et al. (2007 ). For the synthesis of the title compound, see: Li et al. (2011 ). For the structure of ethyl 1-benzyl-3-(4-fluorophenyl)-1H-pyrazole-5-carboxylate, see: Han et al. (2011 ). For applications of nitrogen-containing heterocyclic compounds, see: Ge et al. (2009 , 2011 ).

Experimental

Crystal data

C₁₉H₁₆ClFN₂O₂
M_r = 358.79
Triclinic, $[P \overline 1]$
a = 8.267 (4) Å
b = 10.375 (5) Å
c = 11.368 (5) Å
α = 109.128 (7)°
β = 93.269 (7)°
γ = 104.842 (7)°
V = 879.8 (7) Å³
Z = 2
Mo Kα radiation
μ = 0.24 mm⁻¹
T = 298 K
0.22 × 0.14 × 0.11 mm

Data collection

Bruker SMART APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.949, T_max = 0.974
4589 measured reflections
3091 independent reflections
2570 reflections with I > 2σ(I)
R_int = 0.017

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.117
S = 1.05
3091 reflections
227 parameters
H-atom parameters constrained
Δρ_max = 0.20 e Å⁻³
Δρ_min = −0.32 e Å⁻³

Data collection: SMART (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811017156/fy2010sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811017156/fy2010Isup2.hkl

checkCIF report

Comment top

Synthesis of nitrogen-containing heterocyclic compounds has been a subject of great interest due to their applications in the agrochemical and pharmaceutical fields (Ge et al., 2009, 2011). Some pyrazole derivatives which belong to this category have been of interest for their biological activities. Considerable effort has been devoted to the development of novel pyrazole compounds. We report here the crystal structure of the title compound, (I) (Fig. 1)

Related literature top

For the pharmacological activity of pyrazole compounds, see: Ge et al. (2007). For the synthesis of the title compound, see: Li et al. (2011). For the structure of ethyl 1-benzyl-3-(4-fluorophenyl)-1H-pyrazole-5-carboxylate, see: Han et al. (2011). For applications of nitrogen-containing heterocyclic compounds, see: Ge et al. (2009, 2011).

Experimental top

A mixture of ethyl 3-(4-fluorophenyl)-1H-pyrazole-5-carboxylate (0.02 mol), 1-chloro-4-(chloromethyl)benzene (0.0024 mol) and potassium carbonate (0.02 mol) in acetonitrile (100 ml) was heated to reflux for 3 h. The solvent was removed under reduced pressure and the product was isolated by column chromatography on silica gel (yield 88%). Crystals of (I) suitable for X-ray diffraction were obtained by allowing a refluxed solution of the product in ethyl acetate to cool slowly to room temperature and allowing the solvent to evaporate for 1 d.

Computing details top

Data collection: SMART (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of (I), showing displacement ellipsoids drawn at the 50% probability level.

Ethyl 1-(4-chlorobenzyl)-3-(4-fluorophenyl)-1H-pyrazole-5-carboxylate top

Crystal data top

C₁₉H₁₆ClFN₂O₂	Z = 2
M_r = 358.79	F(000) = 372
Triclinic, P1	D_x = 1.354 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.267 (4) Å	Cell parameters from 2637 reflections
b = 10.375 (5) Å	θ = 2.3–28.0°
c = 11.368 (5) Å	µ = 0.24 mm⁻¹
α = 109.128 (7)°	T = 298 K
β = 93.269 (7)°	Block, colourless
γ = 104.842 (7)°	0.22 × 0.14 × 0.11 mm
V = 879.8 (7) Å³

Data collection top

Bruker SMART APEX CCD diffractometer	3091 independent reflections
Radiation source: fine-focus sealed tube	2570 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.017
ϕ and ω scans	θ_max = 25.1°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −9→9
T_min = 0.949, T_max = 0.974	k = −7→12
4589 measured reflections	l = −13→13

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)] = 0.042	H-atom parameters constrained
wR(F²) = 0.117	w = 1/[σ²(F_o²) + (0.0578P)² + 0.1997P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max < 0.001
3091 reflections	Δρ_max = 0.20 e Å⁻³
227 parameters	Δρ_min = −0.32 e Å⁻³
0 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.377 (15)

Crystal data top

C₁₉H₁₆ClFN₂O₂	γ = 104.842 (7)°
M_r = 358.79	V = 879.8 (7) Å³
Triclinic, P1	Z = 2
a = 8.267 (4) Å	Mo Kα radiation
b = 10.375 (5) Å	µ = 0.24 mm⁻¹
c = 11.368 (5) Å	T = 298 K
α = 109.128 (7)°	0.22 × 0.14 × 0.11 mm
β = 93.269 (7)°

Data collection top

Bruker SMART APEX CCD diffractometer	3091 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	2570 reflections with I > 2σ(I)
T_min = 0.949, T_max = 0.974	R_int = 0.017
4589 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.117	H-atom parameters constrained
S = 1.05	Δρ_max = 0.20 e Å⁻³
3091 reflections	Δρ_min = −0.32 e Å⁻³
227 parameters

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

	x	y	z	U_iso*/U_eq
Cl1	1.50553 (8)	0.97753 (7)	0.28534 (7)	0.0902 (3)
F1	0.58679 (18)	0.70217 (16)	1.03659 (11)	0.0901 (4)
O1	0.8333 (2)	0.38223 (15)	0.13974 (12)	0.0730 (4)
O2	0.85036 (17)	0.24464 (14)	0.25387 (12)	0.0635 (4)
N1	0.76250 (18)	0.58191 (16)	0.36486 (13)	0.0520 (4)
N2	0.72669 (19)	0.64677 (16)	0.47978 (13)	0.0538 (4)
C1	1.2960 (3)	0.8828 (2)	0.28289 (19)	0.0623 (5)
C2	1.2032 (3)	0.7838 (2)	0.17127 (17)	0.0613 (5)
H2	1.2510	0.7663	0.0976	0.074*
C3	1.0381 (3)	0.7106 (2)	0.17021 (16)	0.0581 (5)
H3	0.9750	0.6430	0.0949	0.070*
C4	0.9639 (2)	0.73540 (19)	0.27895 (15)	0.0530 (4)
C5	1.0613 (3)	0.8359 (2)	0.39014 (17)	0.0665 (5)
H5	1.0142	0.8537	0.4641	0.080*
C6	1.2269 (3)	0.9101 (2)	0.39306 (19)	0.0735 (6)
H6	1.2910	0.9774	0.4681	0.088*
C7	0.7810 (2)	0.6583 (2)	0.27612 (17)	0.0589 (5)
H7A	0.7168	0.7269	0.2968	0.071*
H7B	0.7342	0.5910	0.1916	0.071*
C8	0.7893 (2)	0.45469 (18)	0.35425 (15)	0.0489 (4)
C9	0.7673 (2)	0.43606 (18)	0.46724 (15)	0.0502 (4)
H9	0.7764	0.3590	0.4890	0.060*
C10	0.7285 (2)	0.55756 (18)	0.54247 (15)	0.0480 (4)
C11	0.6912 (2)	0.59545 (18)	0.67292 (15)	0.0490 (4)
C12	0.7055 (2)	0.5107 (2)	0.74363 (17)	0.0599 (5)
H12	0.7390	0.4291	0.7082	0.072*
C13	0.6705 (3)	0.5465 (2)	0.86630 (18)	0.0663 (5)
H13	0.6798	0.4896	0.9133	0.080*
C14	0.6221 (2)	0.6670 (2)	0.91642 (17)	0.0633 (5)
C15	0.6065 (3)	0.7534 (2)	0.85037 (18)	0.0642 (5)
H15	0.5733	0.8349	0.8870	0.077*
C16	0.6412 (2)	0.7171 (2)	0.72777 (17)	0.0564 (4)
H16	0.6309	0.7747	0.6817	0.068*
C17	0.8260 (2)	0.35999 (19)	0.23761 (16)	0.0535 (4)
C18	0.8920 (3)	0.1438 (2)	0.1458 (2)	0.0723 (6)
H18A	0.9889	0.1920	0.1161	0.087*
H18B	0.7970	0.1014	0.0776	0.087*
C19	0.9320 (3)	0.0317 (3)	0.1868 (3)	0.0882 (7)
H19A	1.0243	0.0751	0.2555	0.132*
H19B	0.9631	−0.0351	0.1177	0.132*
H19C	0.8343	−0.0171	0.2136	0.132*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0733 (4)	0.0979 (5)	0.1037 (5)	0.0228 (3)	0.0231 (3)	0.0415 (4)
F1	0.1132 (10)	0.1118 (10)	0.0493 (7)	0.0361 (8)	0.0303 (6)	0.0283 (7)
O1	0.1059 (11)	0.0717 (9)	0.0482 (8)	0.0343 (8)	0.0217 (7)	0.0219 (7)
O2	0.0808 (9)	0.0592 (8)	0.0567 (8)	0.0294 (7)	0.0222 (6)	0.0198 (6)
N1	0.0610 (9)	0.0581 (9)	0.0442 (8)	0.0220 (7)	0.0137 (6)	0.0229 (7)
N2	0.0632 (9)	0.0583 (9)	0.0459 (8)	0.0234 (7)	0.0151 (6)	0.0206 (7)
C1	0.0701 (12)	0.0634 (11)	0.0642 (12)	0.0276 (9)	0.0183 (9)	0.0292 (10)
C2	0.0821 (13)	0.0669 (12)	0.0503 (10)	0.0354 (10)	0.0256 (9)	0.0277 (9)
C3	0.0814 (13)	0.0575 (10)	0.0414 (9)	0.0275 (9)	0.0134 (8)	0.0192 (8)
C4	0.0727 (11)	0.0539 (10)	0.0438 (9)	0.0274 (9)	0.0146 (8)	0.0240 (8)
C5	0.0851 (14)	0.0716 (13)	0.0418 (10)	0.0225 (11)	0.0198 (9)	0.0173 (9)
C6	0.0840 (15)	0.0748 (14)	0.0507 (11)	0.0163 (11)	0.0079 (10)	0.0139 (10)
C7	0.0733 (12)	0.0672 (11)	0.0492 (10)	0.0293 (9)	0.0124 (8)	0.0300 (9)
C8	0.0494 (9)	0.0522 (9)	0.0449 (9)	0.0146 (7)	0.0074 (7)	0.0171 (7)
C9	0.0546 (10)	0.0512 (9)	0.0475 (9)	0.0162 (8)	0.0088 (7)	0.0202 (8)
C10	0.0473 (9)	0.0538 (10)	0.0433 (9)	0.0134 (7)	0.0071 (7)	0.0188 (7)
C11	0.0463 (9)	0.0546 (10)	0.0445 (9)	0.0117 (7)	0.0068 (7)	0.0180 (8)
C12	0.0726 (12)	0.0609 (11)	0.0502 (10)	0.0217 (9)	0.0130 (8)	0.0225 (9)
C13	0.0807 (13)	0.0731 (13)	0.0521 (11)	0.0215 (11)	0.0138 (9)	0.0315 (10)
C14	0.0646 (11)	0.0799 (13)	0.0419 (9)	0.0145 (10)	0.0134 (8)	0.0212 (9)
C15	0.0692 (12)	0.0685 (12)	0.0543 (11)	0.0262 (10)	0.0157 (9)	0.0152 (9)
C16	0.0624 (11)	0.0623 (11)	0.0501 (10)	0.0222 (9)	0.0123 (8)	0.0236 (8)
C17	0.0549 (10)	0.0546 (10)	0.0478 (10)	0.0135 (8)	0.0097 (7)	0.0157 (8)
C18	0.0880 (14)	0.0623 (12)	0.0657 (12)	0.0312 (11)	0.0238 (10)	0.0125 (10)
C19	0.0947 (17)	0.0722 (14)	0.112 (2)	0.0396 (13)	0.0408 (14)	0.0357 (14)

Geometric parameters (Å, º) top

Cl1—C1	1.753 (2)	C8—C9	1.375 (2)
F1—C14	1.363 (2)	C8—C17	1.470 (2)
O1—C17	1.210 (2)	C9—C10	1.398 (2)
O2—C17	1.331 (2)	C9—H9	0.9300
O2—C18	1.454 (2)	C10—C11	1.477 (2)
N1—N2	1.348 (2)	C11—C16	1.390 (3)
N1—C8	1.362 (2)	C11—C12	1.392 (2)
N1—C7	1.466 (2)	C12—C13	1.388 (3)
N2—C10	1.343 (2)	C12—H12	0.9300
C1—C2	1.373 (3)	C13—C14	1.366 (3)
C1—C6	1.381 (3)	C13—H13	0.9300
C2—C3	1.379 (3)	C14—C15	1.368 (3)
C2—H2	0.9300	C15—C16	1.387 (3)
C3—C4	1.389 (2)	C15—H15	0.9300
C3—H3	0.9300	C16—H16	0.9300
C4—C5	1.387 (3)	C18—C19	1.488 (3)
C4—C7	1.512 (3)	C18—H18A	0.9700
C5—C6	1.380 (3)	C18—H18B	0.9700
C5—H5	0.9300	C19—H19A	0.9600
C6—H6	0.9300	C19—H19B	0.9600
C7—H7A	0.9700	C19—H19C	0.9600
C7—H7B	0.9700

C17—O2—C18	115.92 (15)	N2—C10—C11	119.71 (15)
N2—N1—C8	111.63 (13)	C9—C10—C11	129.52 (15)
N2—N1—C7	118.43 (15)	C16—C11—C12	118.60 (17)
C8—N1—C7	129.72 (15)	C16—C11—C10	120.50 (16)
C10—N2—N1	105.41 (14)	C12—C11—C10	120.90 (16)
C2—C1—C6	121.27 (19)	C13—C12—C11	120.85 (19)
C2—C1—Cl1	119.37 (15)	C13—C12—H12	119.6
C6—C1—Cl1	119.37 (17)	C11—C12—H12	119.6
C1—C2—C3	118.90 (17)	C14—C13—C12	118.54 (18)
C1—C2—H2	120.6	C14—C13—H13	120.7
C3—C2—H2	120.6	C12—C13—H13	120.7
C2—C3—C4	121.55 (17)	F1—C14—C13	118.73 (19)
C2—C3—H3	119.2	F1—C14—C15	118.72 (19)
C4—C3—H3	119.2	C13—C14—C15	122.55 (18)
C5—C4—C3	118.05 (18)	C14—C15—C16	118.70 (19)
C5—C4—C7	120.71 (16)	C14—C15—H15	120.6
C3—C4—C7	121.22 (16)	C16—C15—H15	120.6
C6—C5—C4	121.21 (18)	C15—C16—C11	120.75 (18)
C6—C5—H5	119.4	C15—C16—H16	119.6
C4—C5—H5	119.4	C11—C16—H16	119.6
C5—C6—C1	119.02 (19)	O1—C17—O2	124.03 (17)
C5—C6—H6	120.5	O1—C17—C8	125.40 (18)
C1—C6—H6	120.5	O2—C17—C8	110.57 (15)
N1—C7—C4	112.17 (14)	O2—C18—C19	107.60 (18)
N1—C7—H7A	109.2	O2—C18—H18A	110.2
C4—C7—H7A	109.2	C19—C18—H18A	110.2
N1—C7—H7B	109.2	O2—C18—H18B	110.2
C4—C7—H7B	109.2	C19—C18—H18B	110.2
H7A—C7—H7B	107.9	H18A—C18—H18B	108.5
N1—C8—C9	106.76 (15)	C18—C19—H19A	109.5
N1—C8—C17	122.96 (15)	C18—C19—H19B	109.5
C9—C8—C17	130.22 (17)	H19A—C19—H19B	109.5
C8—C9—C10	105.43 (15)	C18—C19—H19C	109.5
C8—C9—H9	127.3	H19A—C19—H19C	109.5
C10—C9—H9	127.3	H19B—C19—H19C	109.5
N2—C10—C9	110.77 (15)

C8—N1—N2—C10	−0.88 (18)	C8—C9—C10—N2	−0.08 (19)
C7—N1—N2—C10	−175.99 (14)	C8—C9—C10—C11	179.54 (16)
C6—C1—C2—C3	−0.1 (3)	N2—C10—C11—C16	5.1 (2)
Cl1—C1—C2—C3	−179.55 (14)	C9—C10—C11—C16	−174.51 (17)
C1—C2—C3—C4	0.3 (3)	N2—C10—C11—C12	−174.77 (16)
C2—C3—C4—C5	−0.5 (3)	C9—C10—C11—C12	5.6 (3)
C2—C3—C4—C7	177.88 (16)	C16—C11—C12—C13	0.1 (3)
C3—C4—C5—C6	0.4 (3)	C10—C11—C12—C13	179.94 (17)
C7—C4—C5—C6	−177.99 (18)	C11—C12—C13—C14	−0.2 (3)
C4—C5—C6—C1	−0.1 (3)	C12—C13—C14—F1	179.67 (17)
C2—C1—C6—C5	0.0 (3)	C12—C13—C14—C15	0.2 (3)
Cl1—C1—C6—C5	179.45 (16)	F1—C14—C15—C16	−179.51 (17)
N2—N1—C7—C4	95.64 (18)	C13—C14—C15—C16	0.0 (3)
C8—N1—C7—C4	−78.4 (2)	C14—C15—C16—C11	−0.1 (3)
C5—C4—C7—N1	−57.5 (2)	C12—C11—C16—C15	0.1 (3)
C3—C4—C7—N1	124.17 (18)	C10—C11—C16—C15	−179.79 (16)
N2—N1—C8—C9	0.85 (19)	C18—O2—C17—O1	1.5 (3)
C7—N1—C8—C9	175.25 (16)	C18—O2—C17—C8	−178.52 (16)
N2—N1—C8—C17	178.25 (15)	N1—C8—C17—O1	−1.4 (3)
C7—N1—C8—C17	−7.3 (3)	C9—C8—C17—O1	175.33 (19)
N1—C8—C9—C10	−0.45 (18)	N1—C8—C17—O2	178.63 (15)
C17—C8—C9—C10	−177.60 (17)	C9—C8—C17—O2	−4.6 (3)
N1—N2—C10—C9	0.57 (18)	C17—O2—C18—C19	174.11 (17)
N1—N2—C10—C11	−179.09 (14)

Experimental details

Crystal data
Chemical formula	C₁₉H₁₆ClFN₂O₂
M_r	358.79
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	8.267 (4), 10.375 (5), 11.368 (5)
α, β, γ (°)	109.128 (7), 93.269 (7), 104.842 (7)
V (Å³)	879.8 (7)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.24
Crystal size (mm)	0.22 × 0.14 × 0.11

Data collection
Diffractometer	Bruker SMART APEX CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.949, 0.974
No. of measured, independent and observed [I > 2σ(I)] reflections	4589, 3091, 2570
R_int	0.017
(sin θ/λ)_max (Å⁻¹)	0.596

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.117, 1.05
No. of reflections	3091
No. of parameters	227
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.20, −0.32

Computer programs: SMART (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008).

Acknowledgements

This study was supported by the Natural Science Foundation of Shandong Province (Y2007C135).

References

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