5-Ethyl-2-(4-fluoro­phen­yl)-4-phen­oxy-1H-pyrazol-3(2H)-one

In the title compound, C₁₇H₁₅FN₂O₂, the essentially planar pyrazole ring [maximum deviation = 0.026 (1) Å] makes dihedral angles of 72.06 (7) and 33.05 (7)°, with the phenyl and fluoro­benzene rings, respectively. The dihedral angle between the two six-membered rings is 87.88 (7)°. In the crystal, inter­molecular N—H...O and C—H...F hydrogen bonds link the mol­ecules into layers lying parallel to the bc plane.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.044
• wR factor = 0.119
• Data-to-parameter ratio = 20.8

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT934_ALERT_3_B Number of (Iobs-Icalc)/SigmaW .gt. 10 Outliers .          1

Alert level C
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          3
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          4

Alert level G
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   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
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S1. Comment

Antibacterial and antifungal activities of the azoles are most widely studied and some of them are in clinical practice as anti-microbial agents. However, the azole-resistant strain had led to the development of new antimicrobial compounds. In particular pyrazole derivatives are extensively studied and used as antimicrobial agents. Pyrazole is an important class of heterocyclic compounds and many pyrazole derivatives are reported to have the broad spectrum of biological properties, such as anti-inflammatory, antifungal, herbicidal,anti-tumour, cytotoxic, molecular modelling, and antiviral activities. Pyrazole derivatives also act as antiangiogenic agents, A3 adenosine receptor antagonists, neuropeptide YY5 receptor antagonists, kinase inhibitor for treatment of type 2 diabetes, hyperlipidemia, obesity, and thrombopiotinmimetics. Recently urea derivatives of pyrazoles have been reported as potent inhibitors of p38 kinase. Since the high electronegativity of halogens (particularly chlorine and fluorine) in the aromatic part of the drug molecules play an important role in enhancing their biological activity, we are interested to have 4-fluoro or 4-chloro substitution in the aryls of 1,5-diaryl pyrazoles. As part of our on-going research aiming the synthesis of new antimicrobial compounds, we have reported the synthesis of novel pyrazole derivatives and their microbial activities (Ragavan et al., 2009; 2010). The structure of the title compound, (I), is presented here.

In the title compound (Fig. 1), the molecule consists of two phenyl (C10—C15 and C1—C6) and one pyrazole (N1/N2/C7—C9) rings, all rings are essentially planar. The pyrazole ring (maximum deviation of 0.026 (1) Å at atom N1) makes dihedral angles of 72.06 (7) and 33.05 (7)°, with phenyl (C10—C15) and fluoro substituted phenyl (C1—C6) rings, respectively. The dihedral angle between the two six-membered rings,(C1—C6) and (C10—C15), is 87.88 (7)°. The bond lengths (Allen et al., 1987) and angles are within normal ranges and are comparable to the closely related structures (Shahani et al.,2009; 2010a,b).

In the crystal (Fig. 2), intermolecular N2–H1N2···O2 and C11–H11A···F1 (Table 1) hydrogen bonds link the molecules into two-dimensional arrays parallel to the bc plane.

Related literature

For pyrazole derivatives and their microbial activity, see: Ragavan et al. (2009, 2010). For the synthesis, see: Ragavan et al. (2009). For related structures, see: Shahani et al. (2009, 2010a,b). For hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

S2. Experimental

The compound was synthesized using the literature method (Ragavan et al.,2009) and recrystallized using an ethanol-chloroform 1:1 mixture to yield colourless needles of (I). Yield: 61%. M.p.: 441 K.

S3. Refinement

The hydrogen atom bound to the N2 atom was located in a difference map and allow to refine freely [N–H = 0.899 (18) Å]. All other H atoms were positioned geometrically [range of C–H = 0.93 to 0.97 Å] with U_iso(H) = 1.2 or 1.5 U_eq(C). A rotating-group model was applied for the methyl group

Computing details

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures

	Fig. 1. The molecular structure of (I), showing 50% probability displacement ellipsoids.
	Fig. 2. The crystal packing of (I), viewed along b axis. Intermolecular hydrogen bonds linked the molecules into two-dimensional arrays parallel to the bc plane. H atoms not involved in hydrogen bonds (dashed lines) have been omitted for clarity.

5-Ethyl-2-(4-fluorophenyl)-4-phenoxy-1H-pyrazol-3(2H)-one

Crystal data

C17H15FN2O2	F(000) = 624
Mr = 298.31	Dx = 1.364 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2971 reflections
a = 15.332 (2) Å	θ = 3.0–33.0°
b = 8.6833 (14) Å	µ = 0.10 mm^−1
c = 11.6066 (19) Å	T = 100 K
β = 109.916 (3)°	Needle, colourless
V = 1452.8 (4) Å^3	0.55 × 0.14 × 0.08 mm
Z = 4

Data collection

Bruker APEXII DUO CCD diffractometer	4247 independent reflections
Radiation source: fine-focus sealed tube	3207 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.036
ϕ and ω scans	θmax = 30.0°, θmin = 3.0°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −21→20
Tmin = 0.947, Tmax = 0.992	k = −12→9
12927 measured reflections	l = −16→16

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.119	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ^2(Fo^2) + (0.047P)^2 + 0.4776P] where P = (Fo^2 + 2Fc^2)/3
4247 reflections	(Δ/σ)max < 0.001
204 parameters	Δρmax = 0.34 e Å^−3
0 restraints	Δρmin = −0.24 e Å^−3

Special details

Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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 (Ų)

	x	y	z	Uiso*/Ueq
F1	0.77686 (5)	0.90535 (11)	0.09196 (7)	0.0332 (2)
O1	0.22938 (6)	0.55499 (11)	0.07275 (8)	0.0226 (2)
O2	0.40598 (6)	0.72722 (11)	0.20071 (7)	0.0243 (2)
N1	0.41488 (7)	0.72695 (13)	0.00442 (8)	0.0187 (2)
N2	0.36358 (7)	0.66422 (13)	−0.10812 (9)	0.0192 (2)
C1	0.55898 (8)	0.70430 (15)	−0.03872 (10)	0.0191 (2)
H1A	0.5320	0.6289	−0.0969	0.023*
C2	0.64946 (9)	0.75124 (16)	−0.01831 (11)	0.0215 (3)
H2A	0.6836	0.7098	−0.0634	0.026*
C3	0.68736 (8)	0.86072 (16)	0.07039 (11)	0.0222 (3)
C4	0.63952 (9)	0.92659 (15)	0.13937 (11)	0.0215 (3)
H4A	0.6677	0.9992	0.1994	0.026*
C5	0.54850 (8)	0.88198 (15)	0.11691 (10)	0.0200 (3)
H5A	0.5142	0.9261	0.1607	0.024*
C6	0.50869 (8)	0.77049 (14)	0.02820 (10)	0.0172 (2)
C7	0.37115 (8)	0.69697 (15)	0.08861 (10)	0.0187 (2)
C8	0.28708 (8)	0.62287 (15)	0.01905 (10)	0.0190 (2)
C9	0.28418 (8)	0.60586 (15)	−0.09962 (10)	0.0190 (2)
C10	0.14644 (8)	0.62813 (16)	0.06414 (11)	0.0204 (3)
C11	0.10224 (9)	0.56911 (18)	0.14043 (11)	0.0254 (3)
H11A	0.1284	0.4881	0.1933	0.030*
C12	0.01814 (10)	0.6329 (2)	0.13677 (13)	0.0337 (4)
H12A	−0.0120	0.5947	0.1880	0.040*
C13	−0.02094 (10)	0.7526 (2)	0.05755 (14)	0.0378 (4)
H13A	−0.0772	0.7950	0.0554	0.045*
C14	0.02428 (10)	0.8092 (2)	−0.01883 (13)	0.0330 (3)
H14A	−0.0023	0.8892	−0.0727	0.040*
C15	0.10888 (9)	0.74771 (17)	−0.01581 (11)	0.0252 (3)
H15A	0.1394	0.7863	−0.0665	0.030*
C16	0.21135 (9)	0.53400 (17)	−0.20637 (11)	0.0246 (3)
H16A	0.1673	0.6127	−0.2491	0.030*
H16B	0.1781	0.4578	−0.1764	0.030*
C17	0.25005 (10)	0.45693 (18)	−0.29685 (12)	0.0282 (3)
H17A	0.2009	0.4051	−0.3590	0.042*
H17B	0.2968	0.3836	−0.2542	0.042*
H17C	0.2769	0.5336	−0.3342	0.042*
H1N2	0.3689 (12)	0.706 (2)	−0.1764 (16)	0.035 (4)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
F1	0.0199 (4)	0.0497 (6)	0.0311 (4)	−0.0092 (4)	0.0103 (3)	−0.0079 (4)
O1	0.0193 (4)	0.0301 (5)	0.0232 (4)	0.0039 (4)	0.0136 (3)	0.0076 (4)
O2	0.0251 (4)	0.0367 (6)	0.0138 (4)	0.0009 (4)	0.0100 (3)	−0.0019 (3)
N1	0.0179 (5)	0.0274 (6)	0.0124 (4)	−0.0018 (4)	0.0071 (4)	−0.0017 (4)
N2	0.0192 (5)	0.0275 (6)	0.0120 (4)	−0.0024 (4)	0.0067 (4)	−0.0009 (4)
C1	0.0208 (5)	0.0212 (6)	0.0166 (5)	0.0005 (5)	0.0080 (4)	−0.0013 (4)
C2	0.0211 (6)	0.0265 (7)	0.0200 (5)	0.0019 (5)	0.0109 (5)	−0.0001 (5)
C3	0.0179 (5)	0.0281 (7)	0.0202 (5)	−0.0016 (5)	0.0060 (4)	0.0021 (5)
C4	0.0220 (6)	0.0243 (6)	0.0174 (5)	−0.0009 (5)	0.0059 (4)	−0.0019 (4)
C5	0.0217 (6)	0.0237 (6)	0.0159 (5)	0.0031 (5)	0.0082 (4)	−0.0002 (4)
C6	0.0174 (5)	0.0209 (6)	0.0143 (5)	0.0013 (4)	0.0067 (4)	0.0027 (4)
C7	0.0203 (5)	0.0224 (6)	0.0160 (5)	0.0042 (5)	0.0097 (4)	0.0019 (4)
C8	0.0178 (5)	0.0244 (6)	0.0177 (5)	0.0016 (5)	0.0099 (4)	0.0023 (4)
C9	0.0181 (5)	0.0225 (6)	0.0177 (5)	0.0016 (5)	0.0078 (4)	0.0015 (4)
C10	0.0163 (5)	0.0283 (7)	0.0175 (5)	0.0002 (5)	0.0070 (4)	−0.0029 (4)
C11	0.0191 (6)	0.0394 (8)	0.0193 (6)	−0.0026 (5)	0.0087 (5)	0.0010 (5)
C12	0.0207 (6)	0.0588 (11)	0.0263 (6)	−0.0031 (7)	0.0142 (5)	−0.0045 (6)
C13	0.0218 (6)	0.0590 (11)	0.0344 (7)	0.0097 (7)	0.0119 (6)	−0.0071 (7)
C14	0.0295 (7)	0.0401 (9)	0.0288 (7)	0.0129 (6)	0.0090 (6)	0.0007 (6)
C15	0.0246 (6)	0.0314 (7)	0.0221 (6)	0.0039 (6)	0.0110 (5)	−0.0006 (5)
C16	0.0211 (6)	0.0321 (7)	0.0207 (6)	−0.0027 (5)	0.0071 (5)	−0.0019 (5)
C17	0.0301 (7)	0.0347 (8)	0.0194 (6)	−0.0042 (6)	0.0078 (5)	−0.0055 (5)

Geometric parameters (Å, º)

F1—C3	1.3644 (14)	C8—C9	1.3708 (16)
O1—C8	1.3763 (15)	C9—C16	1.4928 (17)
O1—C10	1.3941 (15)	C10—C15	1.3809 (18)
O2—C7	1.2544 (14)	C10—C11	1.3837 (18)
N1—C7	1.3851 (15)	C11—C12	1.3907 (19)
N1—N2	1.3862 (13)	C11—H11A	0.9300
N1—C6	1.4202 (16)	C12—C13	1.382 (2)
N2—C9	1.3529 (16)	C12—H12A	0.9300
N2—H1N2	0.899 (18)	C13—C14	1.388 (2)
C1—C2	1.3866 (17)	C13—H13A	0.9300
C1—C6	1.3915 (17)	C14—C15	1.3922 (19)
C1—H1A	0.9300	C14—H14A	0.9300
C2—C3	1.3761 (18)	C15—H15A	0.9300
C2—H2A	0.9300	C16—C17	1.5255 (19)
C3—C4	1.3806 (18)	C16—H16A	0.9700
C4—C5	1.3848 (17)	C16—H16B	0.9700
C4—H4A	0.9300	C17—H17A	0.9600
C5—C6	1.3934 (17)	C17—H17B	0.9600
C5—H5A	0.9300	C17—H17C	0.9600
C7—C8	1.4206 (17)
C8—O1—C10	118.93 (10)	N2—C9—C16	122.23 (11)
C7—N1—N2	109.59 (10)	C8—C9—C16	129.65 (12)
C7—N1—C6	127.91 (9)	C15—C10—C11	121.70 (12)
N2—N1—C6	119.98 (9)	C15—C10—O1	123.51 (11)
C9—N2—N1	108.32 (9)	C11—C10—O1	114.77 (11)
C9—N2—H1N2	124.6 (11)	C10—C11—C12	118.95 (13)
N1—N2—H1N2	118.8 (11)	C10—C11—H11A	120.5
C2—C1—C6	119.70 (11)	C12—C11—H11A	120.5
C2—C1—H1A	120.1	C13—C12—C11	120.48 (14)
C6—C1—H1A	120.1	C13—C12—H12A	119.8
C3—C2—C1	118.28 (12)	C11—C12—H12A	119.8
C3—C2—H2A	120.9	C12—C13—C14	119.58 (14)
C1—C2—H2A	120.9	C12—C13—H13A	120.2
F1—C3—C2	118.39 (12)	C14—C13—H13A	120.2
F1—C3—C4	118.40 (11)	C13—C14—C15	120.79 (14)
C2—C3—C4	123.20 (12)	C13—C14—H14A	119.6
C3—C4—C5	118.38 (12)	C15—C14—H14A	119.6
C3—C4—H4A	120.8	C10—C15—C14	118.50 (13)
C5—C4—H4A	120.8	C10—C15—H15A	120.8
C4—C5—C6	119.55 (11)	C14—C15—H15A	120.8
C4—C5—H5A	120.2	C9—C16—C17	113.48 (11)
C6—C5—H5A	120.2	C9—C16—H16A	108.9
C1—C6—C5	120.86 (11)	C17—C16—H16A	108.9
C1—C6—N1	119.90 (11)	C9—C16—H16B	108.9
C5—C6—N1	119.23 (11)	C17—C16—H16B	108.9
O2—C7—N1	123.71 (11)	H16A—C16—H16B	107.7
O2—C7—C8	131.88 (11)	C16—C17—H17A	109.5
N1—C7—C8	104.34 (10)	C16—C17—H17B	109.5
C9—C8—O1	127.09 (11)	H17A—C17—H17B	109.5
C9—C8—C7	109.42 (11)	C16—C17—H17C	109.5
O1—C8—C7	122.36 (10)	H17A—C17—H17C	109.5
N2—C9—C8	108.11 (10)	H17B—C17—H17C	109.5
C7—N1—N2—C9	4.94 (14)	O2—C7—C8—C9	−174.87 (14)
C6—N1—N2—C9	168.32 (11)	N1—C7—C8—C9	2.11 (14)
C6—C1—C2—C3	1.35 (18)	O2—C7—C8—O1	−6.2 (2)
C1—C2—C3—F1	179.00 (11)	N1—C7—C8—O1	170.74 (11)
C1—C2—C3—C4	−0.4 (2)	N1—N2—C9—C8	−3.48 (14)
F1—C3—C4—C5	179.60 (11)	N1—N2—C9—C16	177.94 (12)
C2—C3—C4—C5	−1.0 (2)	O1—C8—C9—N2	−167.13 (12)
C3—C4—C5—C6	1.43 (18)	C7—C8—C9—N2	0.83 (15)
C2—C1—C6—C5	−0.93 (18)	O1—C8—C9—C16	11.3 (2)
C2—C1—C6—N1	177.66 (11)	C7—C8—C9—C16	179.27 (13)
C4—C5—C6—C1	−0.49 (18)	C8—O1—C10—C15	13.96 (18)
C4—C5—C6—N1	−179.09 (11)	C8—O1—C10—C11	−167.62 (11)
C7—N1—C6—C1	137.38 (13)	C15—C10—C11—C12	−0.4 (2)
N2—N1—C6—C1	−22.65 (17)	O1—C10—C11—C12	−178.89 (12)
C7—N1—C6—C5	−44.01 (18)	C10—C11—C12—C13	0.4 (2)
N2—N1—C6—C5	155.96 (11)	C11—C12—C13—C14	0.1 (2)
N2—N1—C7—O2	173.06 (12)	C12—C13—C14—C15	−0.6 (2)
C6—N1—C7—O2	11.4 (2)	C11—C10—C15—C14	−0.1 (2)
N2—N1—C7—C8	−4.24 (13)	O1—C10—C15—C14	178.25 (12)
C6—N1—C7—C8	−165.94 (12)	C13—C14—C15—C10	0.6 (2)
C10—O1—C8—C9	−87.43 (16)	N2—C9—C16—C17	30.45 (18)
C10—O1—C8—C7	106.04 (13)	C8—C9—C16—C17	−147.80 (14)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H1N2···O2^i	0.899 (18)	1.803 (18)	2.6865 (14)	167.1 (16)
C11—H11A···F1^ii	0.93	2.52	3.3441 (16)	147

Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) −x+1, y−1/2, −z+1/2.