2,2,2-Tribromo-N-(2-chloro­phen­yl)acetamide

Abstract

In the title compound, C₈H₅Br₃ClNO, the conformation of the N—H bond is syn to the 2-chloro substituent in the benzene ring. There are no classical inter­molecular hydrogen bonds, but intra­molecular N—H⋯Br and N—H⋯Cl contacts occur.

Related literature

For preparation of the title compound, see: Gowda et al. (2003 ▶). For background to our studies on the effect of the ring and the side-chain substituents on the crystal structures of N-aromatic amides, see: Gowda et al. (2007 ▶, 2009 ▶). For the conformations of other amides, see: Brown (1966 ▶).

Experimental

Crystal data

• C₈H₅Br₃ClNO

• M _r = 406.31

• Orthorhombic,

• a = 9.1947 (6) Å

• b = 12.9645 (7) Å

• c = 9.5213 (6) Å

• V = 1134.98 (12) ų

• Z = 4

• Mo Kα radiation

• μ = 10.86 mm⁻¹

• T = 299 K

• 0.40 × 0.40 × 0.34 mm

Data collection

• Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector

• Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009 ▶) T _min = 0.098, T _max = 0.120

• 4524 measured reflections

• 1645 independent reflections

• 1491 reflections with I > 2σ(I)

• R _int = 0.022

Refinement

• R[F ² > 2σ(F ²)] = 0.027

• wR(F ²) = 0.066

• S = 1.07

• 1645 reflections

• 131 parameters

• 2 restraints

• H atoms treated by a mixture of independent and constrained refinement

• Δρ_max = 0.77 e Å⁻³

• Δρ_min = −0.56 e Å⁻³

• Absolute structure: Flack (1983 ▶), 416 Friedel pairs

• Flack parameter: 0.049 (18)

Data collection: CrysAlis CCD (Oxford Diffraction, 2009 ▶); cell refinement: CrysAlis RED (Oxford Diffraction, 2009 ▶); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: PLATON (Spek, 2009 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N⋯Br1	0.85 (3)	2.78 (8)	3.155 (6)	109 (6)
N1—H1N⋯Cl1	0.85 (3)	2.59 (7)	2.961 (5)	107 (5)

supplementary crystallographic information

Comment

As a part of studying the effect of the ring and the side chain substituents on the crystal structures of N-aromatic amides (Gowda et al., 2007, 2009), in the present work, the structure of N-(2-chlorophenyl)2,2,2-tribromoacetamide (I) has been determined (Fig.1). The conformation of the N—H bond is syn to the 2-chloro substituent in the benzene ring, similar to that observed in N-(2-chlorophenyl)acetamide and N-(2-chlorophenyl)2,2,2-trichloroacetamide (Gowda et al., 2007), but contrary to the anti conformation observed between the N—H bond and the 3-methyl group in N-(3-methylphenyl)2,2,2-tribromoacetamide (Gowda et al., 2009). Further, the conformation of the N—H bond in the structure is anti to the C=O bond in the side chain, similar to that observed in N-(phenyl)2,2,2-tribromoacetamide (Gowda et al., 2009) and other amides (Brown, 1966; Gowda et al., 2007, 2009). The structure shows simultaneous N—H···Br and N—H···Cl intramolecular H-bonding. The packing diagram of the molecules is shown in Fig. 2.

Experimental

The title compound was prepared from 2-chloroaniline, tribromoacetic acid and phosphorylchloride according to the literature method (Gowda et al., 2003). The purity of the compound was checked by determining its melting point. It was further characterized by recording its infrared spectra. Single crystals of the title compound used for X-ray diffraction studies were obtained by a slow evaporation of its ethanolic solution at room temperature.

Refinement

The H atom of the NH group was located in a difference map and later restrained to the distance N—H = 0.86 (3) Å. The other H atoms were positioned with idealized geometry using a riding model [C—H = 0.93 Å]. All H atoms were refined with isotropic displacement parameters set to 1.2 times of the U_eq of the parent atom.

Figures

Fig. 1.

Molecular structure of the title compound, showing the atom labelling scheme. Displacement ellipsoids are drawn at the 50% probability level and the H atoms are represented as small spheres of arbitrary radii.

Fig. 2.

Molecular packing of the title compound with hydrogen bonds shown as dashed lines.

Crystal data

C8H5Br3ClNO	F(000) = 760
Mr = 406.31	Dx = 2.378 Mg m−3
Orthorhombic, Pna21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2n	Cell parameters from 3507 reflections
a = 9.1947 (6) Å	θ = 2.7–27.8°
b = 12.9645 (7) Å	µ = 10.86 mm−1
c = 9.5213 (6) Å	T = 299 K
V = 1134.98 (12) Å3	Rod, colourless
Z = 4	0.40 × 0.40 × 0.34 mm

Data collection

Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector	1645 independent reflections
Radiation source: fine-focus sealed tube	1491 reflections with I > 2σ(I)
graphite	Rint = 0.022
Rotation method data acquisition using ω and φ scans.	θmax = 26.4°, θmin = 2.7°
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009)	h = −11→11
Tmin = 0.098, Tmax = 0.120	k = −16→15
4524 measured reflections	l = −11→6

Refinement

Refinement on F2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.027	w = 1/[σ2(Fo2) + (0.0357P)2 + 1.2795P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.066	(Δ/σ)max = 0.004
S = 1.07	Δρmax = 0.77 e Å−3
1645 reflections	Δρmin = −0.56 e Å−3
131 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
2 restraints	Extinction coefficient: 0.0072 (5)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 416 Friedel pairs
Secondary atom site location: difference Fourier map	Flack parameter: 0.049 (18)

Special details

Experimental. CrysAlis RED (Oxford Diffraction, 2009) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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
Br1	0.56049 (8)	0.28366 (5)	1.15778 (8)	0.0510 (2)
Br2	0.43394 (7)	0.06152 (5)	1.19542 (7)	0.0483 (2)
Br3	0.70743 (6)	0.09279 (5)	1.00260 (9)	0.0474 (2)
Cl1	0.5017 (2)	0.46215 (12)	0.7770 (2)	0.0536 (5)
O1	0.3140 (5)	0.1287 (4)	0.9233 (5)	0.0521 (13)
N1	0.4832 (5)	0.2390 (4)	0.8407 (6)	0.0366 (12)
H1N	0.554 (5)	0.277 (4)	0.866 (9)	0.044*
C1	0.4101 (6)	0.2689 (4)	0.7164 (7)	0.0311 (12)
C2	0.4114 (6)	0.3709 (4)	0.6763 (7)	0.0360 (14)
C3	0.3435 (8)	0.4026 (5)	0.5526 (7)	0.0475 (17)
H3	0.3476	0.4712	0.5244	0.057*
C4	0.2701 (8)	0.3305 (6)	0.4724 (8)	0.0573 (19)
H4	0.2235	0.3506	0.3901	0.069*
C5	0.2660 (9)	0.2308 (6)	0.5136 (9)	0.063 (2)
H5	0.2152	0.1829	0.4598	0.076*
C6	0.3362 (8)	0.1987 (5)	0.6347 (7)	0.0471 (17)
H6	0.3335	0.1296	0.6607	0.057*
C7	0.4282 (6)	0.1716 (4)	0.9346 (6)	0.0278 (12)
C8	0.5253 (6)	0.1542 (4)	1.0638 (7)	0.0288 (12)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Br1	0.0744 (5)	0.0373 (3)	0.0411 (4)	−0.0059 (3)	−0.0169 (4)	−0.0036 (3)
Br2	0.0476 (4)	0.0509 (4)	0.0464 (4)	−0.0058 (3)	0.0000 (3)	0.0248 (3)
Br3	0.0328 (3)	0.0471 (4)	0.0623 (5)	0.0097 (3)	0.0018 (3)	0.0139 (4)
Cl1	0.0620 (10)	0.0384 (8)	0.0604 (12)	−0.0142 (8)	−0.0155 (9)	0.0153 (8)
O1	0.047 (3)	0.067 (3)	0.043 (3)	−0.025 (2)	−0.009 (2)	0.011 (3)
N1	0.040 (3)	0.035 (3)	0.035 (3)	−0.007 (2)	−0.008 (2)	0.013 (3)
C1	0.035 (3)	0.032 (3)	0.026 (3)	0.008 (2)	0.000 (2)	0.004 (2)
C2	0.032 (3)	0.036 (3)	0.040 (4)	0.004 (2)	0.004 (3)	0.004 (3)
C3	0.057 (4)	0.052 (4)	0.033 (4)	0.018 (3)	0.004 (3)	0.018 (3)
C4	0.074 (5)	0.070 (5)	0.028 (4)	0.010 (4)	−0.017 (4)	0.012 (4)
C5	0.092 (5)	0.065 (5)	0.033 (4)	0.011 (4)	−0.020 (4)	−0.016 (4)
C6	0.068 (4)	0.039 (3)	0.034 (4)	0.011 (3)	−0.005 (4)	−0.002 (3)
C7	0.028 (3)	0.027 (3)	0.029 (3)	0.002 (2)	0.000 (2)	0.000 (2)
C8	0.032 (3)	0.027 (3)	0.027 (3)	0.001 (2)	−0.001 (2)	0.008 (2)

Geometric parameters (Å, °)

Br1—C8	1.929 (6)	C2—C3	1.395 (9)
Br2—C8	1.929 (6)	C3—C4	1.383 (10)
Br3—C8	1.944 (6)	C3—H3	0.9300
Cl1—C2	1.735 (7)	C4—C5	1.351 (11)
O1—C7	1.193 (6)	C4—H4	0.9300
N1—C7	1.349 (7)	C5—C6	1.385 (10)
N1—C1	1.415 (8)	C5—H5	0.9300
N1—H1N	0.85 (3)	C6—H6	0.9300
C1—C6	1.377 (9)	C7—C8	1.537 (8)
C1—C2	1.376 (8)
C7—N1—C1	123.6 (5)	C4—C5—C6	121.1 (7)
C7—N1—H1N	118 (6)	C4—C5—H5	119.5
C1—N1—H1N	116 (5)	C6—C5—H5	119.5
C6—C1—C2	118.8 (6)	C1—C6—C5	120.1 (6)
C6—C1—N1	121.7 (5)	C1—C6—H6	119.9
C2—C1—N1	119.4 (6)	C5—C6—H6	119.9
C1—C2—C3	120.9 (6)	O1—C7—N1	124.9 (6)
C1—C2—Cl1	120.4 (5)	O1—C7—C8	121.0 (5)
C3—C2—Cl1	118.7 (5)	N1—C7—C8	114.1 (4)
C4—C3—C2	119.0 (6)	C7—C8—Br1	110.0 (4)
C4—C3—H3	120.5	C7—C8—Br2	111.0 (4)
C2—C3—H3	120.5	Br1—C8—Br2	108.3 (3)
C5—C4—C3	120.0 (6)	C7—C8—Br3	108.7 (4)
C5—C4—H4	120.0	Br1—C8—Br3	110.5 (3)
C3—C4—H4	120.0	Br2—C8—Br3	108.3 (3)
C7—N1—C1—C6	−41.6 (9)	N1—C1—C6—C5	−179.9 (6)
C7—N1—C1—C2	137.9 (6)	C4—C5—C6—C1	0.9 (12)
C6—C1—C2—C3	−2.1 (9)	C1—N1—C7—O1	1.1 (9)
N1—C1—C2—C3	178.4 (6)	C1—N1—C7—C8	−177.9 (5)
C6—C1—C2—Cl1	179.4 (5)	O1—C7—C8—Br1	−121.3 (5)
N1—C1—C2—Cl1	−0.1 (8)	N1—C7—C8—Br1	57.7 (6)
C1—C2—C3—C4	2.2 (10)	O1—C7—C8—Br2	−1.5 (7)
Cl1—C2—C3—C4	−179.4 (5)	N1—C7—C8—Br2	177.5 (4)
C2—C3—C4—C5	−0.7 (11)	O1—C7—C8—Br3	117.5 (5)
C3—C4—C5—C6	−0.9 (12)	N1—C7—C8—Br3	−63.4 (5)
C2—C1—C6—C5	0.6 (10)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···Br1	0.85 (3)	2.78 (8)	3.155 (6)	109 (6)
N1—H1N···Cl1	0.85 (3)	2.59 (7)	2.961 (5)	107 (5)