N-(2-Chloro­phen­yl)acetamide

In the structure of the title compound, C₈H₈ClNO, the conformation of the N—H bond is syn to the ortho-chloro substituent, in contrast to the anti conformation observed for the ortho-methyl substituent in N-(2-methyl­phen­yl)acetamide, although the geometric parameters of these two structures are similar. The mol­ecules are linked into chains through N—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C)= 0.003 Å
• R factor = 0.032
• wR factor = 0.081
• Data-to-parameter ratio = 14.1

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S1. Comment

The structure of N-(2-chlorophenyl)-acetamide has been determined as part of a study on the systematization of the crystal structures of N-aromatic amides (Gowda et al., 2007a, Gowda et al., 2007b, Gowda, Kožíšek, Svoboda & Fuess 2007, Gowda, Kožíšek, Tokarčík & Fuess, 2007). The conformation of the N—H bond is syn to the ortho-chloro substituent (Fig. 1), in contrast to the anti conformation observed for the ortho-methyl substituent in N-(2-methylphenyl)-acetamide (Gowda, Kožíšek, Tokarčík & Fuess, 2007). The geometric parameters of these two structures and other acetanilides are similar (Gowda et al., 2007a,b, Gowda, Kožíšek, Svoboda & Fuess 2007, Gowda, Kožíšek, Tokarčík & Fuess, 2007). The molecules are packed into chains through N—H···O hydrogen bonds (Fig. 2 & Table 1).

Related literature

For related literature, see: Gowda et al. (2003, 2007a, 2007b); Gowda, Kožíšek, Svoboda & Fuess (2007); Gowda, Kožíšek, Tokarčík & Fuess (2007).

S2. Experimental

The title compound was prepared according to the literature method (Gowda et al., 2003). The purity of the compound was checked by determining its melting point. It was characterized by recording its infrared and NMR spectra (Gowda et al., 2003). Single crystals of the title compound were obtained from an ethanolic solution and used for X-ray diffraction studies at room temperature.

S3. Refinement

The H atoms were located in a difference map and their coordinates were refined with U_iso(H) = 1.2 U_eq(parent atom). The methyl group was refined using a riding model and was allowed to rotate but not to tip.

Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003) and ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. Molecular structure of the title compound showing the atom labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small spheres of arbitrary radii.
	Fig. 2. Hydrogen bonding in the title compound. Hydrogen bonds are shown as dashed lines.

N-(2-Chlorophenyl)acetamide

Crystal data

C8H8ClNO	F(000) = 352
Mr = 169.60	Dx = 1.393 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P2yn	Cell parameters from 1844 reflections
a = 4.7468 (4) Å	θ = 2.3–25.0°
b = 11.699 (1) Å	µ = 0.41 mm^−1
c = 14.640 (2) Å	T = 100 K
β = 95.74 (2)°	Needle, colourless
V = 808.92 (15) Å^3	0.40 × 0.12 × 0.04 mm
Z = 4

Data collection

Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector	1641 independent reflections
Radiation source: Enhance (Mo) X-ray Source	1204 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.023
Detector resolution: 8.4012 pixels mm^-1	θmax = 26.4°, θmin = 2.8°
Rotation method data acquisition using ω and φ scans	h = −5→5
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006) using a multifaceted crystal model (Clark & Reid, 1995)	k = −14→14
Tmin = 0.854, Tmax = 0.984	l = −18→18
5681 measured reflections

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)] = 0.032	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.081	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0443P)^2] where P = (Fo^2 + 2Fc^2)/3
1641 reflections	(Δ/σ)max = 0.008
116 parameters	Δρmax = 0.29 e Å^−3
0 restraints	Δρmin = −0.23 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
C1	−0.0446 (3)	0.05702 (15)	0.35962 (11)	0.0146 (4)
C2	0.0451 (4)	0.01850 (15)	0.27730 (12)	0.0166 (4)
C3	−0.0388 (4)	−0.08698 (16)	0.24092 (13)	0.0200 (4)
H3	0.031 (4)	−0.1113 (15)	0.1851 (13)	0.024*
C4	−0.2228 (4)	−0.15359 (16)	0.28474 (13)	0.0216 (4)
H4	−0.278 (4)	−0.2266 (17)	0.2550 (13)	0.026*
C5	−0.3189 (4)	−0.11594 (16)	0.36608 (13)	0.0206 (4)
H5	−0.448 (4)	−0.1583 (16)	0.3943 (12)	0.025*
C6	−0.2289 (4)	−0.01185 (16)	0.40335 (13)	0.0166 (4)
H6	−0.288 (4)	0.0123 (15)	0.4588 (13)	0.020*
C7	−0.1093 (4)	0.23926 (15)	0.43748 (12)	0.0158 (4)
C8	0.0367 (4)	0.34568 (15)	0.47456 (13)	0.0219 (4)
H8A	−0.0056	0.4087	0.4313	0.026*
H8B	0.2417	0.3327	0.4828	0.026*
H8C	−0.0305	0.3651	0.5338	0.026*
N1	0.0540 (3)	0.16230 (13)	0.39826 (10)	0.0142 (3)
H1	0.221 (4)	0.1778 (16)	0.3978 (12)	0.017*
O1	−0.3652 (2)	0.22592 (11)	0.44072 (9)	0.0223 (3)
Cl1	0.27008 (9)	0.10385 (4)	0.21925 (3)	0.02233 (16)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0125 (9)	0.0149 (9)	0.0157 (9)	0.0015 (8)	−0.0020 (7)	0.0011 (8)
C2	0.0135 (9)	0.0195 (10)	0.0172 (9)	0.0006 (8)	0.0039 (7)	0.0035 (8)
C3	0.0178 (9)	0.0221 (11)	0.0197 (10)	0.0027 (8)	0.0005 (8)	−0.0041 (9)
C4	0.0209 (10)	0.0149 (10)	0.0279 (10)	−0.0010 (8)	−0.0036 (9)	−0.0036 (9)
C5	0.0189 (9)	0.0201 (11)	0.0226 (10)	−0.0050 (8)	0.0007 (8)	0.0050 (9)
C6	0.0171 (10)	0.0186 (10)	0.0140 (9)	0.0004 (8)	0.0015 (8)	0.0015 (8)
C7	0.0142 (9)	0.0185 (10)	0.0146 (9)	0.0004 (8)	0.0009 (7)	0.0019 (8)
C8	0.0214 (10)	0.0194 (10)	0.0253 (10)	0.0030 (8)	0.0049 (8)	−0.0035 (9)
N1	0.0083 (7)	0.0152 (8)	0.0193 (8)	−0.0033 (7)	0.0021 (6)	−0.0006 (7)
O1	0.0124 (7)	0.0248 (7)	0.0302 (8)	−0.0008 (6)	0.0039 (6)	−0.0035 (6)
Cl1	0.0220 (3)	0.0250 (3)	0.0214 (2)	−0.0030 (2)	0.00937 (18)	−0.0004 (2)

Geometric parameters (Å, º)

C1—C6	1.391 (2)	C5—H5	0.918 (18)
C1—C2	1.393 (2)	C6—H6	0.928 (18)
C1—N1	1.415 (2)	C7—O1	1.2305 (19)
C2—C3	1.387 (3)	C7—N1	1.353 (2)
C2—Cl1	1.7440 (18)	C7—C8	1.500 (2)
C3—C4	1.376 (3)	C8—H8A	0.9800
C3—H3	0.955 (19)	C8—H8B	0.9800
C4—C5	1.389 (3)	C8—H8C	0.9800
C4—H4	0.983 (19)	N1—H1	0.813 (18)
C5—C6	1.384 (3)
C6—C1—C2	118.13 (16)	C5—C6—C1	120.76 (17)
C6—C1—N1	121.20 (15)	C5—C6—H6	120.3 (11)
C2—C1—N1	120.65 (15)	C1—C6—H6	119.0 (11)
C3—C2—C1	121.30 (17)	O1—C7—N1	122.80 (16)
C3—C2—Cl1	119.26 (14)	O1—C7—C8	120.91 (16)
C1—C2—Cl1	119.45 (14)	N1—C7—C8	116.25 (15)
C4—C3—C2	119.75 (18)	C7—C8—H8A	109.5
C4—C3—H3	121.3 (11)	C7—C8—H8B	109.5
C2—C3—H3	118.9 (11)	H8A—C8—H8B	109.5
C3—C4—C5	119.88 (18)	C7—C8—H8C	109.5
C3—C4—H4	116.1 (11)	H8A—C8—H8C	109.5
C5—C4—H4	124.0 (11)	H8B—C8—H8C	109.5
C6—C5—C4	120.14 (18)	C7—N1—C1	124.61 (14)
C6—C5—H5	119.4 (11)	C7—N1—H1	117.0 (13)
C4—C5—H5	120.4 (11)	C1—N1—H1	118.3 (13)
C6—C1—C2—C3	−2.0 (3)	C4—C5—C6—C1	0.8 (3)
N1—C1—C2—C3	176.81 (15)	C2—C1—C6—C5	0.3 (3)
C6—C1—C2—Cl1	178.65 (13)	N1—C1—C6—C5	−178.47 (15)
N1—C1—C2—Cl1	−2.6 (2)	O1—C7—N1—C1	−2.3 (3)
C1—C2—C3—C4	2.5 (3)	C8—C7—N1—C1	179.90 (15)
Cl1—C2—C3—C4	−178.12 (14)	C6—C1—N1—C7	−42.7 (2)
C2—C3—C4—C5	−1.3 (3)	C2—C1—N1—C7	138.56 (18)
C3—C4—C5—C6	−0.3 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1^i	0.813 (18)	2.079 (18)	2.8630 (19)	161.7 (17)

Symmetry code: (i) x+1, y, z.