5-(4-Chloro­phen­yl)-1-phenyl­pyrazolidin-3-one

The title compound, C₁₅H₁₃ClN₂O, was synthesized by the reaction of ethyl 3-(4-chloro­phen­yl)acrylate and phenyl­hydrazine. Inter­molecular N—H...O and intra­molecular C—H...N hydrogen bonds are effective in the crystal structure. The inter­molecular N—H...O hydrogen bonds link the mol­ecules into dimers.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.008 Å
• R factor = 0.062
• wR factor = 0.178
• Data-to-parameter ratio = 14.3

checkCIF/PLATON results

No syntax errors found



Alert level C
RINTA01_ALERT_3_C  The value of Rint is greater than 0.10
            Rint given   0.123
PLAT020_ALERT_3_C The value of Rint is greater than 0.10 .........       0.12
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        C13
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          8

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

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S1. Comment

Some five-membered azole heterocycles, such as pyrazoles, thiazoles and pyrazole derivatives, are very important chemical and medical intermediates. 1,5-Diarylpyrazoles are particularly useful in the treatment of inflammation and related disorders (Reddy & Bell, 2003). We report here the crystal structure of the title compound, (I).

The molecular structure of (I) is shown in Fig. 1, and selected bond lengths and angles are given in Table 1. Pyrazolidine ring A (N1/N2/C7–C9) adopts a twisted conformation (Low et al., 2003). Because of the presence of the C═O group in ring A, the acidity of the H atoms on C8 may be increased (Zhu et al., 2004). The dihedral angle between the two aromatic rings B (C1–C6) and C (C10–C15) [64.8 (3)°] may be compared with the corresponding value in 5-(4-methoxyphenyl)-1-phenylpyrazolidin-3-one [79.5 (1)°; Hong et al., 2005].

Intramolecular C—H···N and intermolecular N—H···O hydrogen bonds (Table 2) are effective in stabilizing the crystal structure. The intermolecular N—H···O hydrogen bonds link the molecules into dimers (Fig. 2).

S2. Experimental

Ethanolamine (4 ml) and n-butanol (20 ml) were added to a solution of sodium (40 mmol) in anhydrous methanol (9 mol). The methanol was removed by distillation and ethyl 3-(4-chlorophenyl)acrylate (30 mmol) was added. The resulting mixture was refluxed for 1 h at 373 K and then phenylhydrazine (4 ml) was added. The reaction mixture was refluxed for a further 7 h, left to cool to room temperature, acidified with acetic acid (36%), allowed to stand and then filtered, and the filter cake was crystallized from ethyl acetate to give pure compound (I) (yield 5.63 g, 69%, m.p. 433–435 K). Crystals of (I) suitable for X-ray diffraction were obtained by slow evaporation of an ethyl acetate solution.

S3. Refinement

The H atoms were positioned geometrically, with N—H = 0.86 Å, and C—H = 0.93 and 0.98 Å (CH) or 0.97 Å (CH₂), and constrained to ride on their parent atoms with U_iso(H) = 1.2 U_eq(C,N).

Computing details

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXL97; software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. The molecular structure of (I), with displacement ellipsoids drawn at the 30% probability level. The intramolecular C—H···N hydrogen bond is indicated by a dashed line. [No dashed line present]
	Fig. 2. A packing diagram for (I). Dashed lines denote N—H···O hydrogen bonds.

5-(4-Chlorophenyl)-1-phenylpyrazolidin-3-one

Crystal data

C15H13ClN2O	F(000) = 568
Mr = 272.72	Dx = 1.292 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 25 reflections
a = 11.826 (2) Å	θ = 9–12°
b = 10.227 (2) Å	µ = 0.27 mm^−1
c = 12.867 (3) Å	T = 296 K
β = 115.74 (3)°	Block, colourless
V = 1401.8 (6) Å^3	0.30 × 0.30 × 0.10 mm
Z = 4

Data collection

Enraf–Nonius CAD-4 diffractometer	1395 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.123
Graphite monochromator	θmax = 25.0°, θmin = 1.9°
ω/2θ scans	h = 0→14
Absorption correction: ψ scan (North et al., 1968)	k = 0→12
Tmin = 0.925, Tmax = 0.974	l = −15→13
2581 measured reflections	3 standard reflections every 200 reflections
2456 independent reflections	intensity decay: none

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)] = 0.062	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.178	H-atom parameters constrained
S = 1.00	w = 1/[σ^2(Fo^2) + (0.04P)^2 + 3P] where P = (Fo^2 + 2Fc^2)/3
2456 reflections	(Δ/σ)max < 0.001
172 parameters	Δρmax = 0.33 e Å^−3
0 restraints	Δρmin = −0.37 e Å^−3

Special details

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
Cl	0.38800 (13)	0.93994 (17)	0.13705 (13)	0.0866 (5)
O	0.9114 (3)	1.1551 (3)	−0.0514 (2)	0.0512 (8)
N1	0.9859 (3)	1.0623 (3)	0.2309 (3)	0.0463 (9)
N2	0.9867 (3)	1.0536 (4)	0.1233 (3)	0.0502 (9)
H2A	1.0235	0.9905	0.1059	0.060*
C1	1.3372 (6)	1.0928 (7)	0.5131 (6)	0.100 (2)
H1A	1.4152	1.0973	0.5765	0.120*
C2	1.2298 (7)	1.1078 (6)	0.5279 (5)	0.096 (2)
H2B	1.2347	1.1231	0.6010	0.115*
C3	1.1137 (5)	1.1000 (5)	0.4327 (4)	0.0643 (14)
H3A	1.0407	1.1077	0.4427	0.077*
C4	1.1057 (4)	1.0812 (4)	0.3248 (4)	0.0456 (10)
C5	1.2160 (4)	1.0657 (5)	0.3115 (4)	0.0610 (13)
H5A	1.2134	1.0514	0.2391	0.073*
C6	1.3300 (5)	1.0720 (6)	0.4094 (6)	0.0837 (17)
H6A	1.4039	1.0611	0.4014	0.100*
C7	0.9272 (4)	1.1489 (4)	0.0487 (4)	0.0429 (10)
C8	0.8801 (4)	1.2414 (4)	0.1113 (4)	0.0496 (11)
H8A	0.7943	1.2676	0.0627	0.060*
H8B	0.9325	1.3188	0.1359	0.060*
C9	0.8879 (4)	1.1630 (4)	0.2146 (4)	0.0439 (10)
H9A	0.9171	1.2198	0.2826	0.053*
C10	0.7652 (4)	1.1013 (4)	0.1962 (3)	0.0443 (10)
C11	0.7328 (5)	0.9724 (4)	0.1603 (4)	0.0563 (12)
H11A	0.7898	0.9185	0.1488	0.068*
C12	0.6168 (5)	0.9245 (5)	0.1419 (4)	0.0615 (13)
H12A	0.5956	0.8385	0.1179	0.074*
C13	0.5337 (4)	1.0018 (5)	0.1583 (4)	0.0583 (13)
C14	0.5644 (5)	1.1282 (6)	0.1966 (5)	0.0752 (16)
H14A	0.5082	1.1801	0.2109	0.090*
C15	0.6792 (5)	1.1765 (5)	0.2133 (5)	0.0647 (14)
H15A	0.6990	1.2629	0.2368	0.078*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl	0.0680 (9)	0.1070 (12)	0.0857 (10)	−0.0270 (8)	0.0342 (8)	0.0108 (9)
O	0.066 (2)	0.0463 (18)	0.0481 (18)	0.0140 (15)	0.0313 (15)	0.0068 (15)
N1	0.053 (2)	0.050 (2)	0.043 (2)	0.0062 (18)	0.0276 (18)	−0.0061 (17)
N2	0.063 (2)	0.047 (2)	0.045 (2)	0.0212 (19)	0.0277 (18)	0.0017 (18)
C1	0.082 (5)	0.109 (6)	0.069 (4)	0.004 (4)	−0.005 (4)	−0.012 (4)
C2	0.110 (5)	0.092 (5)	0.055 (4)	0.011 (4)	0.007 (4)	−0.013 (3)
C3	0.083 (4)	0.065 (3)	0.045 (3)	0.002 (3)	0.029 (3)	−0.003 (2)
C4	0.060 (3)	0.031 (2)	0.047 (2)	0.003 (2)	0.023 (2)	0.0020 (19)
C5	0.061 (3)	0.057 (3)	0.063 (3)	0.005 (3)	0.026 (3)	0.006 (3)
C6	0.057 (3)	0.086 (4)	0.089 (4)	0.004 (3)	0.014 (3)	0.004 (4)
C7	0.045 (2)	0.040 (2)	0.049 (3)	0.003 (2)	0.025 (2)	0.001 (2)
C8	0.060 (3)	0.034 (2)	0.067 (3)	0.003 (2)	0.040 (2)	−0.003 (2)
C9	0.054 (3)	0.038 (2)	0.047 (2)	0.004 (2)	0.028 (2)	−0.010 (2)
C10	0.051 (2)	0.051 (3)	0.034 (2)	0.000 (2)	0.0209 (19)	−0.0041 (19)
C11	0.069 (3)	0.046 (3)	0.064 (3)	−0.001 (2)	0.038 (3)	−0.007 (2)
C12	0.082 (4)	0.049 (3)	0.055 (3)	−0.021 (3)	0.031 (3)	−0.007 (2)
C13	0.057 (3)	0.073 (3)	0.045 (3)	−0.008 (3)	0.022 (2)	0.008 (2)
C14	0.069 (3)	0.064 (3)	0.111 (5)	0.005 (3)	0.057 (3)	−0.002 (3)
C15	0.065 (3)	0.044 (3)	0.103 (4)	−0.006 (2)	0.053 (3)	−0.013 (3)

Geometric parameters (Å, º)

Cl—C13	1.742 (5)	C6—H6A	0.9300
O—C7	1.220 (5)	C7—C8	1.498 (5)
N1—N2	1.392 (4)	C8—C9	1.521 (6)
N1—C4	1.420 (6)	C8—H8A	0.9700
N1—C9	1.496 (5)	C8—H8B	0.9700
N2—C7	1.334 (5)	C9—C10	1.503 (6)
N2—H2A	0.8600	C9—H9A	0.9800
C1—C6	1.317 (8)	C10—C15	1.367 (6)
C1—C2	1.372 (9)	C10—C11	1.394 (6)
C1—H1A	0.9300	C11—C12	1.377 (6)
C2—C3	1.390 (8)	C11—H11A	0.9300
C2—H2B	0.9300	C12—C13	1.347 (7)
C3—C4	1.364 (6)	C12—H12A	0.9300
C3—H3A	0.9300	C13—C14	1.374 (7)
C4—C5	1.397 (6)	C14—C15	1.371 (7)
C5—C6	1.390 (7)	C14—H14A	0.9300
C5—H5A	0.9300	C15—H15A	0.9300
N2—N1—C4	114.8 (3)	C9—C8—H8A	111.0
N2—N1—C9	104.2 (3)	C7—C8—H8B	111.0
C4—N1—C9	116.8 (3)	C9—C8—H8B	111.0
C7—N2—N1	116.1 (3)	H8A—C8—H8B	109.0
C7—N2—H2A	122.0	N1—C9—C10	111.7 (3)
N1—N2—H2A	122.0	N1—C9—C8	103.5 (3)
C6—C1—C2	120.2 (6)	C10—C9—C8	113.3 (4)
C6—C1—H1A	119.9	N1—C9—H9A	109.4
C2—C1—H1A	119.9	C10—C9—H9A	109.4
C1—C2—C3	119.4 (6)	C8—C9—H9A	109.4
C1—C2—H2B	120.3	C15—C10—C11	118.0 (4)
C3—C2—H2B	120.3	C15—C10—C9	118.2 (4)
C4—C3—C2	120.7 (6)	C11—C10—C9	123.8 (4)
C4—C3—H3A	119.7	C12—C11—C10	120.2 (4)
C2—C3—H3A	119.7	C12—C11—H11A	119.9
C3—C4—C5	119.0 (4)	C10—C11—H11A	119.9
C3—C4—N1	119.2 (4)	C13—C12—C11	120.3 (5)
C5—C4—N1	121.4 (4)	C13—C12—H12A	119.8
C6—C5—C4	118.3 (5)	C11—C12—H12A	119.8
C6—C5—H5A	120.9	C12—C13—C14	120.7 (5)
C4—C5—H5A	120.9	C12—C13—Cl	120.1 (4)
C1—C6—C5	122.4 (6)	C14—C13—Cl	119.2 (4)
C1—C6—H6A	118.8	C15—C14—C13	119.0 (5)
C5—C6—H6A	118.8	C15—C14—H14A	120.5
O—C7—N2	126.1 (4)	C13—C14—H14A	120.5
O—C7—C8	127.7 (4)	C10—C15—C14	121.8 (5)
N2—C7—C8	106.1 (4)	C10—C15—H15A	119.1
C7—C8—C9	104.0 (3)	C14—C15—H15A	119.1
C7—C8—H8A	111.0
C4—N1—N2—C7	−115.3 (4)	C4—N1—C9—C10	−132.7 (4)
C9—N1—N2—C7	13.8 (5)	N2—N1—C9—C8	−22.7 (4)
C6—C1—C2—C3	0.4 (11)	C4—N1—C9—C8	105.1 (4)
C1—C2—C3—C4	−1.8 (9)	C7—C8—C9—N1	23.9 (4)
C2—C3—C4—C5	2.0 (7)	C7—C8—C9—C10	−97.3 (4)
C2—C3—C4—N1	174.5 (5)	N1—C9—C10—C15	161.4 (4)
N2—N1—C4—C3	175.5 (4)	C8—C9—C10—C15	−82.2 (5)
C9—N1—C4—C3	53.1 (5)	N1—C9—C10—C11	−20.0 (6)
N2—N1—C4—C5	−12.2 (6)	C8—C9—C10—C11	96.4 (5)
C9—N1—C4—C5	−134.6 (4)	C15—C10—C11—C12	0.7 (7)
C3—C4—C5—C6	−0.9 (7)	C9—C10—C11—C12	−177.9 (4)
N1—C4—C5—C6	−173.3 (5)	C10—C11—C12—C13	0.0 (7)
C2—C1—C6—C5	0.7 (11)	C11—C12—C13—C14	−1.7 (8)
C4—C5—C6—C1	−0.4 (9)	C11—C12—C13—Cl	−179.0 (4)
N1—N2—C7—O	−175.7 (4)	C12—C13—C14—C15	2.7 (8)
N1—N2—C7—C8	1.9 (5)	Cl—C13—C14—C15	180.0 (4)
O—C7—C8—C9	161.1 (4)	C11—C10—C15—C14	0.3 (8)
N2—C7—C8—C9	−16.5 (5)	C9—C10—C15—C14	179.0 (5)
N2—N1—C9—C10	99.5 (4)	C13—C14—C15—C10	−2.0 (8)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···O^i	0.86	1.94	2.799 (5)	174
C11—H11A···N1	0.93	2.56	2.875 (7)	101

Symmetry code: (i) −x+2, −y+2, −z.