2,2-Dimethyl-N-(2,4,6-trichloro­phen­yl)acetamide

The structure of the title compound, C₁₀H₁₀Cl₃NO, is similar to that of N-(2,4,6-trichloro­phen­yl)-chloro/methyl-acetamides and other acetanilides, with somewhat different geometric parameters. Comparison of the geometric parameters of the title compound with those of the ring and side-chain-substituted acetanilides reveals that substitution either in the benzene ring or in the side chain of the amides changes some of the space groups but also some of the bond lengths, and bond and torsion angles. The mol­ecules in the title compound are packed into chains through N—H...O hydrogen bonding.

Key indicators

• Single-crystal X-ray study
• T = 297 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.060
• wR factor = 0.126
• Data-to-parameter ratio = 17.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT180_ALERT_3_C Check Cell Rounding: # of Values Ending with 0 =          3
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       3.31 Ratio
PLAT222_ALERT_3_C Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       3.04 Ratio
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C8
PLAT340_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...          5

   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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 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
   0 ALERT type 5 Informative message, check

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S1. Comment

As part of a study on the effect of side chain and ring substitutions on the solid state structures of a chemically and biologically significant class of compounds (Gowda et al., 2000; 2004b; 2006; 2007a, b), in the present work, the crystal structure of N-(2,4,6-trichlorophenyl)-2,2-dimethylacetamide (246TCPDMA) has been determined. The structure of 246TCPDMA (Fig. 1) is similar to those of N-(2,4,6-trichlorophenyl)-chloro/methyl-acetamides and other acetanilides, with somewhat different geometric parameters (Gowda et al., 2000; 2004b; 2006; 2007a, b; Mahalakshmi et al., 2002; Nyburg et al., 1987). The comparison of the geometric parameters of the title compound with those of the ring and side chain substituted acetanilides revealed that substitution either in the benzene ring or in the side chain of the amides not only changes the space groups but also some of the bond lengths as well as bond and torsional angles (Gowda et al., 2000; 2004a; 2006; 2007a, b). But to draw general conclusions further substantive data are to be collected with varying substitution patterns. The molecules in the title compound are packed into chains through N—H···O hydrogen bonding (Table 1 & Fig.2).

Related literature

For related literature, see: Gowda et al. (2000, 2006); Gowda, Svoboda & Fuess (2004); Gowda, Usha & Jyothi (2004); Gowda, Foro et al. (2007); Gowda, Kozisek et al. (2007); Mahalakshmi et al. (2002); Nyburg et al. (1987).

S2. Experimental

The title compound was prepared according to the literature method (Gowda et al., 2004b). The purity of the compound was checked by determining its melting point. The compound was further characterized by recording its infrared and NMR spectra (Gowda et al., 2004b). Single crystals of the title compound were obtained from a slow evaporation of an ethanolic solution (2 g in about 30 ml e thanol) and used for X-ray diffraction studies at room temperature.

S3. Refinement

The H atoms were located from the difference Fourier map and their positions refined with U_iso(H) = 1.2 U_eq (parent atom).

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.

2,2-Dimethyl-N-(2,4,6-trichlorophenyl)acetamide

Crystal data

C10H10Cl3NO	F(000) = 544
Mr = 266.54	Dx = 1.456 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P2yn	Cell parameters from 2291 reflections
a = 4.7310 (6) Å	θ = 2.6–24.4°
b = 24.042 (2) Å	µ = 0.73 mm^−1
c = 10.799 (1) Å	T = 297 K
β = 98.01 (1)°	Needle, colourless
V = 1216.3 (2) Å^3	0.50 × 0.12 × 0.06 mm
Z = 4

Data collection

Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector	2460 independent reflections
Radiation source: Enhance (Mo) X-ray Source	1574 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.039
Detector resolution: 8.4012 pixels mm^-1	θmax = 26.4°, θmin = 4.2°
Rotation method data acquisition using ω and φ scans	h = −5→5
Absorption correction: multi-scan [CrysAlis RED (Oxford Diffraction, 2006); analytical numeric absorption correction using a multifaceted crystal model based on expressions derived by Clark & Reid (1995)]	k = −29→27
Tmin = 0.713, Tmax = 0.958	l = −13→13
8334 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.060	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.126	w = 1/[σ^2(Fo^2) + (0.0366P)^2 + 1.2703P] where P = (Fo^2 + 2Fc^2)/3
S = 1.08	(Δ/σ)max = 0.002
2460 reflections	Δρmax = 0.36 e Å^−3
145 parameters	Δρmin = −0.34 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0137 (15)

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	0.8638 (6)	0.09310 (12)	0.2959 (3)	0.0344 (7)
C2	0.7415 (7)	0.06534 (13)	0.1894 (3)	0.0387 (8)
C3	0.8267 (7)	0.01277 (13)	0.1585 (3)	0.0467 (9)
H3	0.7398	−0.0051	0.0868	0.056*
C4	1.0425 (8)	−0.01217 (13)	0.2364 (4)	0.0504 (9)
C5	1.1702 (8)	0.01276 (14)	0.3435 (3)	0.0516 (9)
H5	1.3160	−0.0050	0.3954	0.062*
C6	1.0776 (7)	0.06514 (14)	0.3730 (3)	0.0427 (8)
C7	0.9518 (7)	0.19206 (13)	0.3283 (3)	0.0380 (8)
C8	0.8228 (7)	0.24621 (14)	0.3627 (4)	0.0503 (9)
H8	0.624 (8)	0.2474 (14)	0.326 (3)	0.060*
C9	0.9660 (9)	0.29551 (15)	0.3124 (5)	0.0736 (13)
H9A	0.9525	0.2925	0.2231	0.088*
H9B	1.1633	0.2964	0.3484	0.088*
H9C	0.8736	0.3291	0.3335	0.088*
C10	0.8362 (14)	0.2489 (2)	0.5023 (5)	0.114 (2)
H10A	1.0320	0.2500	0.5403	0.137*
H10B	0.7454	0.2166	0.5311	0.137*
H10C	0.7396	0.2817	0.5247	0.137*
N1	0.7771 (5)	0.14716 (11)	0.3235 (3)	0.0378 (7)
H1	0.612 (7)	0.1525 (14)	0.323 (3)	0.045*
O1	1.1986 (5)	0.18779 (9)	0.3089 (3)	0.0553 (7)
Cl1	0.4698 (2)	0.09734 (4)	0.09091 (9)	0.0612 (3)
Cl2	1.1579 (3)	−0.07790 (4)	0.19711 (12)	0.0811 (4)
Cl3	1.2321 (2)	0.09475 (4)	0.51250 (9)	0.0664 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0292 (16)	0.0317 (16)	0.0439 (17)	−0.0019 (14)	0.0108 (14)	−0.0012 (15)
C2	0.0346 (17)	0.0366 (18)	0.0439 (18)	−0.0016 (14)	0.0025 (15)	0.0015 (15)
C3	0.051 (2)	0.0364 (18)	0.053 (2)	−0.0018 (17)	0.0069 (17)	−0.0129 (16)
C4	0.055 (2)	0.0306 (17)	0.067 (2)	0.0045 (17)	0.0132 (19)	−0.0036 (17)
C5	0.054 (2)	0.0374 (19)	0.060 (2)	0.0092 (17)	−0.0016 (18)	0.0010 (17)
C6	0.0432 (19)	0.0400 (19)	0.0445 (19)	−0.0037 (16)	0.0045 (16)	−0.0009 (15)
C7	0.0301 (17)	0.0353 (17)	0.0480 (19)	−0.0023 (15)	0.0033 (15)	−0.0055 (15)
C8	0.0336 (18)	0.0375 (19)	0.081 (3)	−0.0016 (16)	0.0139 (19)	−0.0164 (18)
C9	0.078 (3)	0.037 (2)	0.109 (4)	0.002 (2)	0.022 (3)	−0.002 (2)
C10	0.198 (6)	0.067 (3)	0.092 (4)	−0.006 (4)	0.069 (4)	−0.029 (3)
N1	0.0254 (13)	0.0336 (14)	0.0556 (17)	−0.0005 (12)	0.0095 (13)	−0.0090 (12)
O1	0.0287 (13)	0.0439 (14)	0.096 (2)	−0.0027 (11)	0.0178 (12)	−0.0062 (13)
Cl1	0.0599 (6)	0.0559 (6)	0.0614 (6)	0.0128 (5)	−0.0142 (5)	−0.0093 (5)
Cl2	0.0946 (9)	0.0417 (5)	0.1062 (9)	0.0224 (5)	0.0108 (7)	−0.0166 (6)
Cl3	0.0807 (8)	0.0583 (6)	0.0527 (6)	0.0012 (5)	−0.0165 (5)	−0.0049 (5)

Geometric parameters (Å, º)

C1—C2	1.385 (4)	C7—N1	1.356 (4)
C1—C6	1.391 (4)	C7—C8	1.506 (4)
C1—N1	1.407 (4)	C8—C10	1.501 (6)
C2—C3	1.382 (4)	C8—C9	1.504 (5)
C2—Cl1	1.731 (3)	C8—H8	0.97 (4)
C3—C4	1.368 (5)	C9—H9A	0.9600
C3—H3	0.9300	C9—H9B	0.9600
C4—C5	1.367 (5)	C9—H9C	0.9600
C4—Cl2	1.743 (3)	C10—H10A	0.9600
C5—C6	1.385 (5)	C10—H10B	0.9600
C5—H5	0.9300	C10—H10C	0.9600
C6—Cl3	1.733 (3)	N1—H1	0.79 (3)
C7—O1	1.219 (3)
C2—C1—C6	116.7 (3)	C10—C8—C9	111.8 (4)
C2—C1—N1	121.4 (3)	C10—C8—C7	108.8 (4)
C6—C1—N1	121.9 (3)	C9—C8—C7	111.9 (3)
C3—C2—C1	122.6 (3)	C10—C8—H8	108 (2)
C3—C2—Cl1	118.4 (3)	C9—C8—H8	107 (2)
C1—C2—Cl1	119.0 (2)	C7—C8—H8	109 (2)
C4—C3—C2	118.1 (3)	C8—C9—H9A	109.5
C4—C3—H3	121.0	C8—C9—H9B	109.5
C2—C3—H3	121.0	H9A—C9—H9B	109.5
C5—C4—C3	122.2 (3)	C8—C9—H9C	109.5
C5—C4—Cl2	119.1 (3)	H9A—C9—H9C	109.5
C3—C4—Cl2	118.7 (3)	H9B—C9—H9C	109.5
C4—C5—C6	118.5 (3)	C8—C10—H10A	109.5
C4—C5—H5	120.8	C8—C10—H10B	109.5
C6—C5—H5	120.8	H10A—C10—H10B	109.5
C5—C6—C1	121.9 (3)	C8—C10—H10C	109.5
C5—C6—Cl3	117.7 (3)	H10A—C10—H10C	109.5
C1—C6—Cl3	120.4 (3)	H10B—C10—H10C	109.5
O1—C7—N1	121.3 (3)	C7—N1—C1	123.3 (3)
O1—C7—C8	123.1 (3)	C7—N1—H1	118 (3)
N1—C7—C8	115.6 (3)	C1—N1—H1	118 (3)
C6—C1—C2—C3	−0.8 (5)	C2—C1—C6—C5	1.8 (5)
N1—C1—C2—C3	178.5 (3)	N1—C1—C6—C5	−177.6 (3)
C6—C1—C2—Cl1	178.8 (2)	C2—C1—C6—Cl3	−176.8 (2)
N1—C1—C2—Cl1	−1.8 (4)	N1—C1—C6—Cl3	3.9 (4)
C1—C2—C3—C4	−0.6 (5)	O1—C7—C8—C10	−96.7 (4)
Cl1—C2—C3—C4	179.7 (3)	N1—C7—C8—C10	81.4 (4)
C2—C3—C4—C5	1.3 (5)	O1—C7—C8—C9	27.4 (5)
C2—C3—C4—Cl2	−178.7 (3)	N1—C7—C8—C9	−154.5 (3)
C3—C4—C5—C6	−0.4 (6)	O1—C7—N1—C1	−0.3 (5)
Cl2—C4—C5—C6	179.6 (3)	C8—C7—N1—C1	−178.4 (3)
C4—C5—C6—C1	−1.2 (5)	C2—C1—N1—C7	−115.8 (3)
C4—C5—C6—Cl3	177.4 (3)	C6—C1—N1—C7	63.5 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1^i	0.79 (3)	2.12 (3)	2.889 (3)	165 (3)

Symmetry code: (i) x−1, y, z.