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ISSN: 2056-9890

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

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[Crafts, A. S. (1957). Adv. Pest Control Res. 1, 39-79.]). For our work on the synthesis of heterocyclic compounds, see: Khan et al. (2009[Khan, M. A., Tahir, M. N., Ather, A. Q., Shaheen, M. & Khan, R. A. (2009). Acta Cryst. E65, o1615.]). For a related structure, see: Wang et al. (2009[Wang, Y., Wan, R., Han, F. & Wang, P. (2009). Acta Cryst. E65, o1761.]). For graph-set notation, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C11H8Cl2N2O2

  • Mr = 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[Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.982, Tmax = 0.988

  • 10353 measured reflections

  • 2861 independent reflections

  • 2232 reflections with I > 2σ(I)

  • Rint = 0.025

Refinement
  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.093

  • S = 1.04

  • 2861 reflections

  • 154 parameters

  • H-atom parameters constrained

  • Δρmax = 0.25 e Å−3

  • Δρmin = −0.29 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA 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[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information


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%.

Refinement top

The H-atoms were positioned geometrically (C–H = 0.93–0.97 Å) and were included in the refinement in the riding model approximation, with Uiso(H) = xUeq(C), where x = 1.2 for all H-atoms.

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
[Figure 1] 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.
[Figure 2] 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
C11H8Cl2N2O2Z = 2
Mr = 271.09F(000) = 276
Triclinic, P1Dx = 1.551 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 4.2030 (1) ÅCell parameters from 2920 reflections
b = 10.3074 (3) Åθ = 2.6–27.9°
c = 13.4966 (4) ŵ = 0.55 mm1
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 tube2232 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
Detector resolution: 7.50 pixels mm-1θmax = 28.4°, θmin = 2.0°
ω scansh = 55
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
k = 1313
Tmin = 0.982, Tmax = 0.988l = 1717
10353 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.093H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0378P)2 + 0.1536P]
where P = (Fo2 + 2Fc2)/3
2861 reflections(Δ/σ)max = 0.001
154 parametersΔρmax = 0.25 e Å3
0 restraintsΔρmin = 0.29 e Å3
Crystal data top
C11H8Cl2N2O2γ = 88.335 (1)°
Mr = 271.09V = 580.53 (3) Å3
Triclinic, P1Z = 2
a = 4.2030 (1) ÅMo Kα radiation
b = 10.3074 (3) ŵ = 0.55 mm1
c = 13.4966 (4) ÅT = 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)
Tmin = 0.982, Tmax = 0.988Rint = 0.025
10353 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.093H-atom parameters constrained
S = 1.04Δρmax = 0.25 e Å3
2861 reflectionsΔρmin = 0.29 e Å3
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
xyzUiso*/Ueq
Cl10.18429 (10)1.01977 (4)0.34325 (3)0.0568 (2)
Cl20.65932 (16)0.65004 (6)0.58253 (4)0.0775 (2)
O10.5309 (3)0.88439 (11)0.18509 (8)0.0484 (4)
O20.4918 (3)0.66285 (12)0.08285 (9)0.0547 (4)
N10.8767 (3)0.72296 (12)0.03954 (9)0.0409 (4)
N21.0808 (3)0.81744 (14)0.07931 (11)0.0508 (5)
C10.5754 (3)0.82450 (15)0.27460 (11)0.0409 (5)
C20.4121 (3)0.87940 (15)0.35859 (12)0.0414 (5)
C30.4354 (4)0.82649 (16)0.45278 (12)0.0484 (5)
C40.6248 (4)0.71690 (17)0.46376 (13)0.0499 (5)
C50.7924 (4)0.66131 (17)0.38241 (13)0.0534 (6)
C60.7676 (4)0.71501 (17)0.28800 (13)0.0498 (5)
C70.7588 (4)0.86184 (16)0.10197 (12)0.0456 (5)
C80.6884 (4)0.74046 (15)0.05091 (11)0.0404 (5)
C91.2064 (5)0.77078 (19)0.16381 (13)0.0589 (6)
C101.0901 (5)0.6484 (2)0.17990 (13)0.0609 (7)
C110.8813 (4)0.62017 (17)0.09989 (13)0.0523 (6)
H30.325010.864160.508190.0580*
H50.921910.587860.391010.0641*
H60.880720.677440.232990.0597*
H7A0.970860.853580.124000.0547*
H7B0.757020.935570.054840.0547*
H91.356140.814060.208170.0706*
H101.145750.597350.234560.0731*
H110.763040.545160.087990.0627*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0547 (3)0.0481 (2)0.0649 (3)0.0094 (2)0.0060 (2)0.0084 (2)
Cl20.1045 (4)0.0712 (3)0.0552 (3)0.0028 (3)0.0074 (3)0.0102 (2)
O10.0497 (6)0.0498 (7)0.0447 (6)0.0070 (5)0.0004 (5)0.0064 (5)
O20.0566 (7)0.0542 (7)0.0528 (7)0.0212 (6)0.0022 (5)0.0033 (5)
N10.0431 (7)0.0386 (7)0.0406 (7)0.0048 (5)0.0022 (5)0.0017 (5)
N20.0541 (8)0.0445 (8)0.0516 (8)0.0087 (6)0.0033 (6)0.0038 (6)
C10.0385 (8)0.0399 (8)0.0448 (8)0.0053 (6)0.0030 (6)0.0079 (6)
C20.0361 (8)0.0366 (8)0.0511 (9)0.0043 (6)0.0006 (6)0.0085 (6)
C30.0473 (9)0.0488 (9)0.0476 (9)0.0087 (7)0.0058 (7)0.0087 (7)
C40.0561 (10)0.0465 (9)0.0476 (9)0.0078 (8)0.0065 (7)0.0006 (7)
C50.0583 (10)0.0432 (9)0.0600 (11)0.0039 (8)0.0119 (8)0.0065 (8)
C60.0516 (9)0.0471 (9)0.0509 (9)0.0043 (7)0.0042 (7)0.0130 (7)
C70.0496 (9)0.0410 (8)0.0451 (8)0.0060 (7)0.0028 (7)0.0059 (7)
C80.0407 (8)0.0400 (8)0.0408 (8)0.0041 (6)0.0049 (6)0.0005 (6)
C90.0600 (11)0.0630 (12)0.0498 (10)0.0000 (9)0.0086 (8)0.0045 (8)
C100.0696 (12)0.0647 (12)0.0471 (10)0.0031 (10)0.0024 (8)0.0134 (9)
C110.0586 (10)0.0470 (9)0.0524 (10)0.0032 (8)0.0067 (8)0.0114 (8)
Geometric parameters (Å, º) top
Cl1—C21.7290 (15)C4—C51.376 (2)
Cl2—C41.7362 (18)C5—C61.380 (2)
O1—C11.3613 (18)C7—C81.506 (2)
O1—C71.417 (2)C9—C101.400 (3)
O2—C81.200 (2)C10—C111.343 (3)
N1—N21.3695 (19)C3—H30.9300
N1—C81.397 (2)C5—H50.9300
N1—C111.363 (2)C6—H60.9300
N2—C91.309 (2)C7—H7A0.9700
C1—C21.393 (2)C7—H7B0.9700
C1—C61.386 (2)C9—H90.9300
C2—C31.374 (2)C10—H100.9300
C3—C41.375 (2)C11—H110.9300
Cl1···O12.8447 (12)C2···C6i3.476 (2)
Cl1···C1i3.5263 (15)C3···C5i3.474 (2)
Cl1···C2i3.5736 (14)C5···C2viii3.469 (2)
Cl1···Cl2ii3.6862 (7)C5···C3viii3.474 (2)
Cl2···Cl1ii3.6862 (7)C6···O23.188 (2)
Cl1···H9iii3.0200C6···C1viii3.592 (2)
Cl1···H3iv3.0300C6···C2viii3.476 (2)
Cl2···H10v3.1400C6···C83.252 (2)
Cl2···H5vi3.0100C7···N2iii3.387 (2)
O1···Cl12.8447 (12)C8···N2i3.313 (2)
O1···O22.7368 (17)C8···C63.252 (2)
O2···N2i3.2665 (19)C9···C11viii3.370 (3)
O2···O12.7368 (17)C9···N1viii3.445 (2)
O2···N1i3.2466 (18)C11···C9i3.370 (3)
O2···C13.1942 (19)C11···O2vii3.339 (2)
O2···C63.188 (2)C6···H7A2.6600
O2···C11vii3.339 (2)C7···H62.6200
O1···H7Ai2.6100C8···H62.7200
O2···H62.7500H3···Cl1iv3.0300
O2···H112.7700H5···Cl2vi3.0100
O2···H11vii2.4200H6···O22.7500
N1···O2viii3.2466 (18)H6···C72.6200
N1···C9i3.445 (2)H6···C82.7200
N2···O2viii3.2665 (19)H6···H7A2.3000
N2···C8viii3.313 (2)H7A···O1viii2.6100
N2···C7iii3.387 (2)H7A···N22.7700
N2···H7A2.7700H7A···C62.6600
N2···H7B2.4800H7A···H62.3000
N2···H7Biii2.7000H7B···N22.4800
C1···Cl1viii3.5263 (14)H7B···N2iii2.7000
C1···O23.1942 (19)H9···Cl1iii3.0200
C1···C6i3.592 (2)H10···Cl2ix3.1400
C2···Cl1viii3.5736 (14)H11···O22.7700
C2···C5i3.469 (2)H11···O2vii2.4200
C1—O1—C7118.85 (12)N2—C9—C10112.42 (17)
N2—N1—C8120.45 (13)C9—C10—C11105.58 (16)
N2—N1—C11111.72 (13)N1—C11—C10106.55 (16)
C8—N1—C11127.80 (13)C2—C3—H3121.00
N1—N2—C9103.74 (14)C4—C3—H3121.00
O1—C1—C2116.28 (13)C4—C5—H5120.00
O1—C1—C6125.34 (14)C6—C5—H5120.00
C2—C1—C6118.38 (14)C1—C6—H6120.00
Cl1—C2—C1118.80 (12)C5—C6—H6120.00
Cl1—C2—C3119.68 (12)O1—C7—H7A109.00
C1—C2—C3121.49 (14)O1—C7—H7B109.00
C2—C3—C4118.88 (15)C8—C7—H7A109.00
Cl2—C4—C3119.31 (13)C8—C7—H7B109.00
Cl2—C4—C5119.64 (14)H7A—C7—H7B108.00
C3—C4—C5121.04 (16)N2—C9—H9124.00
C4—C5—C6119.73 (16)C10—C9—H9124.00
C1—C6—C5120.47 (16)C9—C10—H10127.00
O1—C7—C8111.44 (13)C11—C10—H10127.00
O2—C8—N1121.06 (14)N1—C11—H11127.00
O2—C8—C7124.89 (14)C10—C11—H11127.00
N1—C8—C7114.05 (13)
C7—O1—C1—C2160.01 (13)C6—C1—C2—C30.8 (2)
C7—O1—C1—C620.0 (2)O1—C1—C6—C5179.24 (15)
C1—O1—C7—C885.03 (17)C2—C1—C6—C50.8 (2)
C8—N1—N2—C9177.90 (15)Cl1—C2—C3—C4178.20 (13)
C11—N1—N2—C90.21 (18)C1—C2—C3—C40.0 (2)
N2—N1—C8—O2174.44 (14)C2—C3—C4—Cl2179.37 (12)
N2—N1—C8—C76.0 (2)C2—C3—C4—C50.8 (3)
C11—N1—C8—O23.3 (3)Cl2—C4—C5—C6179.41 (14)
C11—N1—C8—C7176.21 (15)C3—C4—C5—C60.9 (3)
N2—N1—C11—C100.18 (19)C4—C5—C6—C10.0 (3)
C8—N1—C11—C10177.76 (16)O1—C7—C8—O29.1 (2)
N1—N2—C9—C100.2 (2)O1—C7—C8—N1171.34 (13)
O1—C1—C2—Cl12.56 (18)N2—C9—C10—C110.1 (2)
O1—C1—C2—C3179.19 (14)C9—C10—C11—N10.1 (2)
C6—C1—C2—Cl1177.44 (12)
Symmetry codes: (i) x1, y, z; (ii) x+1, y+2, z+1; (iii) x+2, y+2, z; (iv) x, y+2, z+1; (v) x1, 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, z1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···O2vii0.932.423.339 (2)170
Symmetry code: (vii) x+1, y+1, z.

Experimental details

Crystal data
Chemical formulaC11H8Cl2N2O2
Mr271.09
Crystal system, space groupTriclinic, 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)
V3)580.53 (3)
Z2
Radiation typeMo Kα
µ (mm1)0.55
Crystal size (mm)0.30 × 0.22 × 0.18
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.982, 0.988
No. of measured, independent and
observed [I > 2σ(I)] reflections
10353, 2861, 2232
Rint0.025
(sin θ/λ)max1)0.668
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.093, 1.04
No. of reflections2861
No. of parameters154
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)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···AD—HH···AD···AD—H···A
C11—H11···O2i0.932.423.339 (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.

References

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First citationKhan, M. A., Tahir, M. N., Ather, A. Q., Shaheen, M. & Khan, R. A. (2009). Acta Cryst. E65, o1615.  Web of Science CSD CrossRef IUCr Journals Google Scholar
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First citationWang, Y., Wan, R., Han, F. & Wang, P. (2009). Acta Cryst. E65, o1761.  Web of Science CSD CrossRef IUCr Journals Google Scholar

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ISSN: 2056-9890
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