2-(2,4-Dichloro­phen­oxy)-1-(1H-pyrazol-1-yl)ethanone

Karamat, A.; Tahir, M.N.; Khan, M.A.; Ather, A.Q.

doi:10.1107/S1600536810035087

organic compounds

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ISSN: 2056-9890

Volume 66| Part 10| October 2010| Page o2476

doi:10.1107/S1600536810035087

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2-(2,4-Dichlorophenoxy)-1-(1H-pyrazol-1-yl)ethanone

Aisha Karamat,^a M. Nawaz Tahir,^b ^* Misbahul Ain Khan ^a and Abdul Qayyum Ather ^c,^d

^aInstitute of Chemistry, University of the Punjab, Lahore, Pakistan, ^bDepartment of Physics, University of Sargodha, Sargodha, Pakistan, ^cDepartment of Chemistry, Islamia University, Bahawalpur, Pakistan, and ^dApplied Chemistry Research Center, PCSIR Laboratories Complex, Lahore 54600, Pakistan
^*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 27 August 2010; accepted 31 August 2010; online 4 September 2010)

In the title compound, C₁₁H₈Cl₂N₂O₂, the 2,4-dichlorophenoxy and 1H-pyrazole groups are almost planar [r.m.s. deviations of 0.0157 and 0.0008 Å, respectively] and are oriented at a dihedral angle of 64.17 (5)° with respect to one another. In the crystal, the molecules are stabilized in the form of dimers due to inversion-related C—H⋯O hydrogen bonds, with R₂²(10) ring motifs.

Related literature

Aryloxyacetic acid and its various derivatives are used as herbicides and pesticides, see: Crafts (1957 ). For our work on the synthesis of heterocyclic compounds, see: Khan et al. (2009 ). For a related structure, see: Wang et al. (2009 ). For graph-set notation, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₁₁H₈Cl₂N₂O₂
M_r = 271.09
Triclinic, $[P \overline 1]$
a = 4.2030 (1) Å
b = 10.3074 (3) Å
c = 13.4966 (4) Å
α = 87.510 (2)°
β = 83.774 (1)°
γ = 88.335 (1)°
V = 580.53 (3) Å³
Z = 2
Mo Kα radiation
μ = 0.55 mm⁻¹
T = 296 K
0.30 × 0.22 × 0.18 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.982, T_max = 0.988
10353 measured reflections
2861 independent reflections
2232 reflections with I > 2σ(I)
R_int = 0.025

Refinement

R[F² > 2σ(F²)] = 0.035
wR(F²) = 0.093
S = 1.04
2861 reflections
154 parameters
H-atom parameters constrained
Δρ_max = 0.25 e Å⁻³
Δρ_min = −0.29 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C11—H11⋯O2ⁱ	0.93	2.42	3.339 (2)	170
Symmetry code: (i) -x+1, -y+1, -z.

Data collection: APEX2 (Bruker, 2009 ); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ) and PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810035087/si2292sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810035087/si2292Isup2.hkl

checkCIF report

Comment top

Aryloxyacetic acid and its various derivatives are used as herbicides and pesticides (Crafts, 1957). During our research on the synthesis of heterocyclic compounds in our laboratories (Khan et al., 2009), we have isolated the title compound (I, Fig. 1).

The crystal structure of 5-(2,4-dichlorophenoxymethyl)-1,3,4-thiadiazol-2-amine has been published (Wang et al., 2009) which is related to the title compound.

In the title compound, 2,4-dichlorophenoxy group A (O1/C1—C6/CL1/CL2) and 1H-pyrazole group B (N1/N2/C9–C11) are planar with r. m. s. deviations of 0.0157 and 0.0008 Å, respectively. The dihedral angle between A/B is 64.17 (5)°. The central group C (C7/C8/O2) is of course planar. The dihedral angle between A/C and B/C is 69.23 (8) and 5.07 (25)°, respectively. The molecules are stabilized in the form of dimers (Table 1, Fig. 2) due to inversion related C—H···O type of H-bondings with R₂²(10) ring motifs (Bernstein et al., 1995).

Related literature top

Aryloxyacetic acid and its various derivatives are used as herbicides and pesticides, see: Crafts (1957). For our work on the synthesis of heterocyclic compounds, see: Khan et al. (2009). For a related structure, see: Wang et al. (2009). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

A mixture of 2,4-dichlorophenoxyacetic acid (0.5 g; 2.25 mmole) and 1 ml of thionyl chloride was heated under reflux for 1 h. Then an excess of pyrazole (0.5 g) in 5 ml of chloroform was added to the refluxing mixture and heated for a further period of 1.5 h. The solvents were removed and the residue dissolved in chloroform and washed with saturated sodium bicarbonate, dried and let crystallize to give pale brown prisms of (I).

Yield, 84%.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top

	Fig. 1. View of the title compound with the atom numbering scheme. The thermal ellipsoids are drawn at the 50% probability level. H-atoms are shown as small spheres of arbitrary radii.
	Fig. 2. Packing section of the title compound (PLATON: Spek, 2009) showing that molecules are stabilized in the form of dimers.

2-(2,4-Dichlorophenoxy)-1-(1H-pyrazol-1-yl)ethanone top

Crystal data top

C₁₁H₈Cl₂N₂O₂	Z = 2
M_r = 271.09	F(000) = 276
Triclinic, P1	D_x = 1.551 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 4.2030 (1) Å	Cell parameters from 2920 reflections
b = 10.3074 (3) Å	θ = 2.6–27.9°
c = 13.4966 (4) Å	µ = 0.55 mm⁻¹
α = 87.510 (2)°	T = 296 K
β = 83.774 (1)°	Prismatic, pale brown
γ = 88.335 (1)°	0.30 × 0.22 × 0.18 mm
V = 580.53 (3) Å³

Data collection top

Bruker Kappa APEXII CCD diffractometer	2861 independent reflections
Radiation source: fine-focus sealed tube	2232 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.025
Detector resolution: 7.50 pixels mm^-1	θ_max = 28.4°, θ_min = 2.0°
ω scans	h = −5→5
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −13→13
T_min = 0.982, T_max = 0.988	l = −17→17
10353 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.093	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0378P)² + 0.1536P] where P = (F_o² + 2F_c²)/3
2861 reflections	(Δ/σ)_max = 0.001
154 parameters	Δρ_max = 0.25 e Å⁻³
0 restraints	Δρ_min = −0.29 e Å⁻³

Crystal data top

C₁₁H₈Cl₂N₂O₂	γ = 88.335 (1)°
M_r = 271.09	V = 580.53 (3) Å³
Triclinic, P1	Z = 2
a = 4.2030 (1) Å	Mo Kα radiation
b = 10.3074 (3) Å	µ = 0.55 mm⁻¹
c = 13.4966 (4) Å	T = 296 K
α = 87.510 (2)°	0.30 × 0.22 × 0.18 mm
β = 83.774 (1)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	2861 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	2232 reflections with I > 2σ(I)
T_min = 0.982, T_max = 0.988	R_int = 0.025
10353 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.035	0 restraints
wR(F²) = 0.093	H-atom parameters constrained
S = 1.04	Δρ_max = 0.25 e Å⁻³
2861 reflections	Δρ_min = −0.29 e Å⁻³
154 parameters

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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	0.18429 (10)	1.01977 (4)	0.34325 (3)	0.0568 (2)
Cl2	0.65932 (16)	0.65004 (6)	0.58253 (4)	0.0775 (2)
O1	0.5309 (3)	0.88439 (11)	0.18509 (8)	0.0484 (4)
O2	0.4918 (3)	0.66285 (12)	0.08285 (9)	0.0547 (4)
N1	0.8767 (3)	0.72296 (12)	−0.03954 (9)	0.0409 (4)
N2	1.0808 (3)	0.81744 (14)	−0.07931 (11)	0.0508 (5)
C1	0.5754 (3)	0.82450 (15)	0.27460 (11)	0.0409 (5)
C2	0.4121 (3)	0.87940 (15)	0.35859 (12)	0.0414 (5)
C3	0.4354 (4)	0.82649 (16)	0.45278 (12)	0.0484 (5)
C4	0.6248 (4)	0.71690 (17)	0.46376 (13)	0.0499 (5)
C5	0.7924 (4)	0.66131 (17)	0.38241 (13)	0.0534 (6)
C6	0.7676 (4)	0.71501 (17)	0.28800 (13)	0.0498 (5)
C7	0.7588 (4)	0.86184 (16)	0.10197 (12)	0.0456 (5)
C8	0.6884 (4)	0.74046 (15)	0.05091 (11)	0.0404 (5)
C9	1.2064 (5)	0.77078 (19)	−0.16381 (13)	0.0589 (6)
C10	1.0901 (5)	0.6484 (2)	−0.17990 (13)	0.0609 (7)
C11	0.8813 (4)	0.62017 (17)	−0.09989 (13)	0.0523 (6)
H3	0.32501	0.86416	0.50819	0.0580*
H5	0.92191	0.58786	0.39101	0.0641*
H6	0.88072	0.67744	0.23299	0.0597*
H7A	0.97086	0.85358	0.12400	0.0547*
H7B	0.75702	0.93557	0.05484	0.0547*
H9	1.35614	0.81406	−0.20817	0.0706*
H10	1.14575	0.59735	−0.23456	0.0731*
H11	0.76304	0.54516	−0.08799	0.0627*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0547 (3)	0.0481 (2)	0.0649 (3)	0.0094 (2)	0.0060 (2)	−0.0084 (2)
Cl2	0.1045 (4)	0.0712 (3)	0.0552 (3)	0.0028 (3)	−0.0074 (3)	0.0102 (2)
O1	0.0497 (6)	0.0498 (7)	0.0447 (6)	0.0070 (5)	−0.0004 (5)	−0.0064 (5)
O2	0.0566 (7)	0.0542 (7)	0.0528 (7)	−0.0212 (6)	0.0022 (5)	−0.0033 (5)
N1	0.0431 (7)	0.0386 (7)	0.0406 (7)	−0.0048 (5)	−0.0022 (5)	−0.0017 (5)
N2	0.0541 (8)	0.0445 (8)	0.0516 (8)	−0.0087 (6)	0.0033 (6)	0.0038 (6)
C1	0.0385 (8)	0.0399 (8)	0.0448 (8)	−0.0053 (6)	−0.0030 (6)	−0.0079 (6)
C2	0.0361 (8)	0.0366 (8)	0.0511 (9)	−0.0043 (6)	0.0006 (6)	−0.0085 (6)
C3	0.0473 (9)	0.0488 (9)	0.0476 (9)	−0.0087 (7)	0.0058 (7)	−0.0087 (7)
C4	0.0561 (10)	0.0465 (9)	0.0476 (9)	−0.0078 (8)	−0.0065 (7)	−0.0006 (7)
C5	0.0583 (10)	0.0432 (9)	0.0600 (11)	0.0039 (8)	−0.0119 (8)	−0.0065 (8)
C6	0.0516 (9)	0.0471 (9)	0.0509 (9)	0.0043 (7)	−0.0042 (7)	−0.0130 (7)
C7	0.0496 (9)	0.0410 (8)	0.0451 (8)	−0.0060 (7)	0.0028 (7)	−0.0059 (7)
C8	0.0407 (8)	0.0400 (8)	0.0408 (8)	−0.0041 (6)	−0.0049 (6)	−0.0005 (6)
C9	0.0600 (11)	0.0630 (12)	0.0498 (10)	0.0000 (9)	0.0086 (8)	0.0045 (8)
C10	0.0696 (12)	0.0647 (12)	0.0471 (10)	0.0031 (10)	0.0024 (8)	−0.0134 (9)
C11	0.0586 (10)	0.0470 (9)	0.0524 (10)	−0.0032 (8)	−0.0067 (8)	−0.0114 (8)

Geometric parameters (Å, º) top

Cl1—C2	1.7290 (15)	C4—C5	1.376 (2)
Cl2—C4	1.7362 (18)	C5—C6	1.380 (2)
O1—C1	1.3613 (18)	C7—C8	1.506 (2)
O1—C7	1.417 (2)	C9—C10	1.400 (3)
O2—C8	1.200 (2)	C10—C11	1.343 (3)
N1—N2	1.3695 (19)	C3—H3	0.9300
N1—C8	1.397 (2)	C5—H5	0.9300
N1—C11	1.363 (2)	C6—H6	0.9300
N2—C9	1.309 (2)	C7—H7A	0.9700
C1—C2	1.393 (2)	C7—H7B	0.9700
C1—C6	1.386 (2)	C9—H9	0.9300
C2—C3	1.374 (2)	C10—H10	0.9300
C3—C4	1.375 (2)	C11—H11	0.9300

Cl1···O1	2.8447 (12)	C2···C6ⁱ	3.476 (2)
Cl1···C1ⁱ	3.5263 (15)	C3···C5ⁱ	3.474 (2)
Cl1···C2ⁱ	3.5736 (14)	C5···C2^viii	3.469 (2)
Cl1···Cl2ⁱⁱ	3.6862 (7)	C5···C3^viii	3.474 (2)
Cl2···Cl1ⁱⁱ	3.6862 (7)	C6···O2	3.188 (2)
Cl1···H9ⁱⁱⁱ	3.0200	C6···C1^viii	3.592 (2)
Cl1···H3^iv	3.0300	C6···C2^viii	3.476 (2)
Cl2···H10^v	3.1400	C6···C8	3.252 (2)
Cl2···H5^vi	3.0100	C7···N2ⁱⁱⁱ	3.387 (2)
O1···Cl1	2.8447 (12)	C8···N2ⁱ	3.313 (2)
O1···O2	2.7368 (17)	C8···C6	3.252 (2)
O2···N2ⁱ	3.2665 (19)	C9···C11^viii	3.370 (3)
O2···O1	2.7368 (17)	C9···N1^viii	3.445 (2)
O2···N1ⁱ	3.2466 (18)	C11···C9ⁱ	3.370 (3)
O2···C1	3.1942 (19)	C11···O2^vii	3.339 (2)
O2···C6	3.188 (2)	C6···H7A	2.6600
O2···C11^vii	3.339 (2)	C7···H6	2.6200
O1···H7Aⁱ	2.6100	C8···H6	2.7200
O2···H6	2.7500	H3···Cl1^iv	3.0300
O2···H11	2.7700	H5···Cl2^vi	3.0100
O2···H11^vii	2.4200	H6···O2	2.7500
N1···O2^viii	3.2466 (18)	H6···C7	2.6200
N1···C9ⁱ	3.445 (2)	H6···C8	2.7200
N2···O2^viii	3.2665 (19)	H6···H7A	2.3000
N2···C8^viii	3.313 (2)	H7A···O1^viii	2.6100
N2···C7ⁱⁱⁱ	3.387 (2)	H7A···N2	2.7700
N2···H7A	2.7700	H7A···C6	2.6600
N2···H7B	2.4800	H7A···H6	2.3000
N2···H7Bⁱⁱⁱ	2.7000	H7B···N2	2.4800
C1···Cl1^viii	3.5263 (14)	H7B···N2ⁱⁱⁱ	2.7000
C1···O2	3.1942 (19)	H9···Cl1ⁱⁱⁱ	3.0200
C1···C6ⁱ	3.592 (2)	H10···Cl2^ix	3.1400
C2···Cl1^viii	3.5736 (14)	H11···O2	2.7700
C2···C5ⁱ	3.469 (2)	H11···O2^vii	2.4200

C1—O1—C7	118.85 (12)	N2—C9—C10	112.42 (17)
N2—N1—C8	120.45 (13)	C9—C10—C11	105.58 (16)
N2—N1—C11	111.72 (13)	N1—C11—C10	106.55 (16)
C8—N1—C11	127.80 (13)	C2—C3—H3	121.00
N1—N2—C9	103.74 (14)	C4—C3—H3	121.00
O1—C1—C2	116.28 (13)	C4—C5—H5	120.00
O1—C1—C6	125.34 (14)	C6—C5—H5	120.00
C2—C1—C6	118.38 (14)	C1—C6—H6	120.00
Cl1—C2—C1	118.80 (12)	C5—C6—H6	120.00
Cl1—C2—C3	119.68 (12)	O1—C7—H7A	109.00
C1—C2—C3	121.49 (14)	O1—C7—H7B	109.00
C2—C3—C4	118.88 (15)	C8—C7—H7A	109.00
Cl2—C4—C3	119.31 (13)	C8—C7—H7B	109.00
Cl2—C4—C5	119.64 (14)	H7A—C7—H7B	108.00
C3—C4—C5	121.04 (16)	N2—C9—H9	124.00
C4—C5—C6	119.73 (16)	C10—C9—H9	124.00
C1—C6—C5	120.47 (16)	C9—C10—H10	127.00
O1—C7—C8	111.44 (13)	C11—C10—H10	127.00
O2—C8—N1	121.06 (14)	N1—C11—H11	127.00
O2—C8—C7	124.89 (14)	C10—C11—H11	127.00
N1—C8—C7	114.05 (13)

C7—O1—C1—C2	160.01 (13)	C6—C1—C2—C3	−0.8 (2)
C7—O1—C1—C6	−20.0 (2)	O1—C1—C6—C5	−179.24 (15)
C1—O1—C7—C8	85.03 (17)	C2—C1—C6—C5	0.8 (2)
C8—N1—N2—C9	−177.90 (15)	Cl1—C2—C3—C4	−178.20 (13)
C11—N1—N2—C9	0.21 (18)	C1—C2—C3—C4	0.0 (2)
N2—N1—C8—O2	174.44 (14)	C2—C3—C4—Cl2	179.37 (12)
N2—N1—C8—C7	−6.0 (2)	C2—C3—C4—C5	0.8 (3)
C11—N1—C8—O2	−3.3 (3)	Cl2—C4—C5—C6	−179.41 (14)
C11—N1—C8—C7	176.21 (15)	C3—C4—C5—C6	−0.9 (3)
N2—N1—C11—C10	−0.18 (19)	C4—C5—C6—C1	0.0 (3)
C8—N1—C11—C10	177.76 (16)	O1—C7—C8—O2	−9.1 (2)
N1—N2—C9—C10	−0.2 (2)	O1—C7—C8—N1	171.34 (13)
O1—C1—C2—Cl1	−2.56 (18)	N2—C9—C10—C11	0.1 (2)
O1—C1—C2—C3	179.19 (14)	C9—C10—C11—N1	0.1 (2)
C6—C1—C2—Cl1	177.44 (12)

Symmetry codes: (i) x−1, y, z; (ii) −x+1, −y+2, −z+1; (iii) −x+2, −y+2, −z; (iv) −x, −y+2, −z+1; (v) x−1, y, z+1; (vi) −x+2, −y+1, −z+1; (vii) −x+1, −y+1, −z; (viii) x+1, y, z; (ix) x+1, y, z−1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C11—H11···O2^vii	0.93	2.42	3.339 (2)	170

Symmetry code: (vii) −x+1, −y+1, −z.

Experimental details

Crystal data
Chemical formula	C₁₁H₈Cl₂N₂O₂
M_r	271.09
Crystal system, space group	Triclinic, P1
Temperature (K)	296
a, b, c (Å)	4.2030 (1), 10.3074 (3), 13.4966 (4)
α, β, γ (°)	87.510 (2), 83.774 (1), 88.335 (1)
V (Å³)	580.53 (3)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.55
Crystal size (mm)	0.30 × 0.22 × 0.18

Data collection
Diffractometer	Bruker Kappa APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.982, 0.988
No. of measured, independent and observed [I > 2σ(I)] reflections	10353, 2861, 2232
R_int	0.025
(sin θ/λ)_max (Å⁻¹)	0.668

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.093, 1.04
No. of reflections	2861
No. of parameters	154
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.29

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C11—H11···O2ⁱ	0.93	2.42	3.339 (2)	170

Symmetry code: (i) −x+1, −y+1, −z.

Acknowledgements

The authors acknowledge the provision of funds for the purchase of diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha, Pakistan.

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