2,2,2-Trichloro-N-(3,4-dimethyl­phen­yl)acetamide

The conformation of the N—H bond in the title compound, C₁₀H₁₀Cl₃NO, is anti to the C=O bond. The amide H atom exhibits both intra­molecular N—H...Cl and inter­molecular N—H...O hydrogen bonding. The latter inter­actions link the mol­ecules into infinite chains.

Key indicators

• Single-crystal X-ray study
• T = 299 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.057
• wR factor = 0.151
• Data-to-parameter ratio = 17.4

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT242_ALERT_2_B Check Low       Ueq as Compared to Neighbors for         C8

Alert level C
            Value of measurement temperature given =   299.000
            Value of melting point given =     0.000
PLAT340_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...          5

   0 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   1 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
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 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 of the effect of ring and side chain substitutions on the crystal structures of aromatic amides (Gowda et al., 2007; 2008; 2009), the structure of 2,2,2-trichloro-N-(3,4-dimethylphenyl)acetamide has been determined. The conformation of the N—H bond in the title compound is anti to the 3-methyl substituent in the aromatic ring similar to that observed with respect to the 3-chloro substituent in N- (3,4-dichlorophenyl)-2,2,2-trichloroacetamide (Gowda et al., 2007), but in contrast to the syn conformation observed with respect to the 3-methyl substituent in N-(3,4-dimethylphenyl)acetamide (Gowda et al., 2008). The conformation of the C=O bond in the structure is anti to the N—H bond similar to that observed in other amides. The amide H atom exhibits both N—H···Cl intramolecular and N—H···O intermolecular hydrogen bonding. The molecules in (I) are linked into infinite chains through intermolecular N—H···O hydrogen bonding (Table 1, Fig. 2).

Related literature

For the preparation of the title compound, see: Shilpa & Gowda (2007). For related structures, see: Gowda et al. (2007, 2008, 2009)

S2. Experimental

The title compound was prepared according to the literature method (Shilpa & Gowda, 2007). Single crystals were obtained from the slow evaporation of an ethanolic solution.

S3. Refinement

The H atoms were positioned with idealized geometry using a riding model with C—H = 0.93–0.96 Å, N—H = 0.86 Å, and were refined with isotropic displacement parameters set to 1.2 times of the U_eq of the parent atom.

Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2004); cell refinement: CrysAlis RED (Oxford Diffraction, 2007); data reduction: CrysAlis RED (Oxford Diffraction, 2007); 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 (Sheldrick, 2008).

Figures

	Fig. 1. Molecular structure of the title compound, showing the atom labeling scheme and displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. Molecular packing of the title compound with hydrogen bonding shown as dashed lines.

2,2,2-Trichloro-N-(3,4-dimethylphenyl)acetamide

Crystal data

C10H10Cl3NO	F(000) = 544
Mr = 266.54	Dx = 1.495 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3672 reflections
a = 5.9003 (8) Å	θ = 2.3–27.6°
b = 20.843 (2) Å	µ = 0.75 mm^−1
c = 9.996 (1) Å	T = 299 K
β = 105.53 (1)°	Prism, colourless
V = 1184.4 (2) Å^3	0.46 × 0.40 × 0.30 mm
Z = 4

Data collection

Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector	2407 independent reflections
Radiation source: fine-focus sealed tube	1952 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.015
Rotation method data acquisition using ω and ϕ scans	θmax = 26.4°, θmin = 2.3°
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007)	h = −7→7
Tmin = 0.726, Tmax = 0.807	k = −25→26
9395 measured reflections	l = −12→12

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)] = 0.057	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.151	H-atom parameters constrained
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0592P)^2 + 1.4852P] where P = (Fo^2 + 2Fc^2)/3
2407 reflections	(Δ/σ)max < 0.001
138 parameters	Δρmax = 0.96 e Å^−3
0 restraints	Δρmin = −0.88 e Å^−3

Special details

Experimental. Absorption correction: CrysAlis RED (Oxford Diffraction, 2007) 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
Cl1	1.2122 (2)	0.19521 (5)	0.59191 (11)	0.0833 (4)
Cl2	1.1512 (2)	0.15721 (6)	0.31037 (12)	0.0939 (5)
Cl3	0.8043 (2)	0.12567 (5)	0.45005 (16)	0.0919 (4)
O1	0.8060 (5)	0.25550 (12)	0.2520 (2)	0.0643 (7)
N1	0.8025 (4)	0.28196 (11)	0.4703 (2)	0.0403 (5)
H1N	0.8600	0.2723	0.5563	0.048*
C1	0.6475 (5)	0.33590 (13)	0.4375 (3)	0.0377 (6)
C2	0.6550 (5)	0.37830 (13)	0.3319 (3)	0.0399 (6)
H2	0.7657	0.3724	0.2819	0.048*
C3	0.4996 (5)	0.42941 (13)	0.2998 (3)	0.0413 (6)
C4	0.3341 (5)	0.43886 (14)	0.3749 (3)	0.0459 (7)
C5	0.3325 (6)	0.39622 (17)	0.4814 (4)	0.0552 (8)
H5	0.2243	0.4024	0.5329	0.066*
C6	0.4852 (6)	0.34532 (15)	0.5131 (3)	0.0500 (7)
H6	0.4796	0.3174	0.5848	0.060*
C7	0.8629 (5)	0.24601 (13)	0.3758 (3)	0.0391 (6)
C8	1.0067 (5)	0.18464 (14)	0.4322 (3)	0.0440 (7)
C9	0.5074 (7)	0.47305 (17)	0.1813 (4)	0.0618 (9)
H9A	0.6361	0.4609	0.1449	0.074*
H9B	0.5285	0.5166	0.2138	0.074*
H9C	0.3625	0.4695	0.1096	0.074*
C10	0.1610 (7)	0.49358 (19)	0.3417 (4)	0.0662 (10)
H10A	0.2428	0.5334	0.3672	0.079*
H10B	0.0457	0.4884	0.3929	0.079*
H10C	0.0843	0.4937	0.2441	0.079*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0948 (8)	0.0602 (6)	0.0657 (6)	0.0180 (5)	−0.0288 (5)	−0.0006 (4)
Cl2	0.1151 (9)	0.1008 (9)	0.0806 (7)	0.0593 (7)	0.0517 (7)	0.0208 (6)
Cl3	0.0866 (8)	0.0481 (5)	0.1423 (11)	−0.0182 (5)	0.0329 (7)	0.0060 (6)
O1	0.0981 (18)	0.0639 (14)	0.0272 (10)	0.0322 (13)	0.0104 (11)	−0.0009 (10)
N1	0.0564 (14)	0.0378 (12)	0.0244 (10)	0.0055 (10)	0.0067 (10)	0.0019 (9)
C1	0.0476 (15)	0.0331 (13)	0.0305 (13)	−0.0007 (11)	0.0074 (11)	−0.0030 (10)
C2	0.0472 (15)	0.0398 (14)	0.0344 (14)	0.0002 (12)	0.0141 (12)	0.0006 (11)
C3	0.0482 (16)	0.0346 (14)	0.0389 (14)	−0.0022 (12)	0.0078 (12)	0.0003 (11)
C4	0.0460 (16)	0.0386 (15)	0.0520 (17)	−0.0001 (12)	0.0113 (13)	−0.0036 (13)
C5	0.0551 (19)	0.0589 (19)	0.060 (2)	0.0054 (15)	0.0295 (16)	−0.0003 (16)
C6	0.0630 (19)	0.0491 (17)	0.0430 (16)	0.0002 (15)	0.0230 (14)	0.0058 (13)
C7	0.0475 (15)	0.0370 (14)	0.0305 (13)	0.0016 (12)	0.0064 (11)	−0.0009 (11)
C8	0.0501 (17)	0.0389 (15)	0.0418 (15)	0.0020 (12)	0.0100 (13)	0.0007 (12)
C9	0.073 (2)	0.0528 (19)	0.063 (2)	0.0143 (17)	0.0238 (18)	0.0199 (16)
C10	0.059 (2)	0.057 (2)	0.084 (3)	0.0139 (17)	0.0217 (19)	0.0043 (19)

Geometric parameters (Å, º)

Cl1—C8	1.741 (3)	C4—C5	1.389 (5)
Cl2—C8	1.759 (3)	C4—C10	1.507 (4)
Cl3—C8	1.755 (3)	C5—C6	1.373 (5)
O1—C7	1.209 (3)	C5—H5	0.9300
N1—C7	1.327 (3)	C6—H6	0.9300
N1—C1	1.431 (3)	C7—C8	1.555 (4)
N1—H1N	0.8600	C9—H9A	0.9600
C1—C6	1.383 (4)	C9—H9B	0.9600
C1—C2	1.387 (4)	C9—H9C	0.9600
C2—C3	1.386 (4)	C10—H10A	0.9600
C2—H2	0.9300	C10—H10B	0.9600
C3—C4	1.395 (4)	C10—H10C	0.9600
C3—C9	1.504 (4)
C7—N1—C1	123.9 (2)	O1—C7—N1	125.6 (3)
C7—N1—H1N	118.0	O1—C7—C8	118.7 (2)
C1—N1—H1N	118.0	N1—C7—C8	115.5 (2)
C6—C1—C2	119.6 (3)	C7—C8—Cl1	114.0 (2)
C6—C1—N1	118.7 (2)	C7—C8—Cl3	107.0 (2)
C2—C1—N1	121.7 (2)	Cl1—C8—Cl3	108.74 (17)
C3—C2—C1	120.8 (3)	C7—C8—Cl2	109.6 (2)
C3—C2—H2	119.6	Cl1—C8—Cl2	109.15 (17)
C1—C2—H2	119.6	Cl3—C8—Cl2	108.17 (17)
C2—C3—C4	120.0 (3)	C3—C9—H9A	109.5
C2—C3—C9	119.3 (3)	C3—C9—H9B	109.5
C4—C3—C9	120.8 (3)	H9A—C9—H9B	109.5
C5—C4—C3	118.1 (3)	C3—C9—H9C	109.5
C5—C4—C10	120.6 (3)	H9A—C9—H9C	109.5
C3—C4—C10	121.3 (3)	H9B—C9—H9C	109.5
C6—C5—C4	122.2 (3)	C4—C10—H10A	109.5
C6—C5—H5	118.9	C4—C10—H10B	109.5
C4—C5—H5	118.9	H10A—C10—H10B	109.5
C5—C6—C1	119.4 (3)	C4—C10—H10C	109.5
C5—C6—H6	120.3	H10A—C10—H10C	109.5
C1—C6—H6	120.3	H10B—C10—H10C	109.5
C7—N1—C1—C6	140.0 (3)	C4—C5—C6—C1	0.3 (5)
C7—N1—C1—C2	−39.4 (4)	C2—C1—C6—C5	0.6 (5)
C6—C1—C2—C3	−1.0 (4)	N1—C1—C6—C5	−178.9 (3)
N1—C1—C2—C3	178.5 (3)	C1—N1—C7—O1	3.8 (5)
C1—C2—C3—C4	0.4 (4)	C1—N1—C7—C8	−172.3 (2)
C1—C2—C3—C9	−177.9 (3)	O1—C7—C8—Cl1	145.1 (3)
C2—C3—C4—C5	0.5 (4)	N1—C7—C8—Cl1	−38.5 (3)
C9—C3—C4—C5	178.7 (3)	O1—C7—C8—Cl3	−94.6 (3)
C2—C3—C4—C10	−179.4 (3)	N1—C7—C8—Cl3	81.8 (3)
C9—C3—C4—C10	−1.1 (5)	O1—C7—C8—Cl2	22.4 (4)
C3—C4—C5—C6	−0.8 (5)	N1—C7—C8—Cl2	−161.1 (2)
C10—C4—C5—C6	179.0 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O1^i	0.86	2.14	2.917 (3)	149
N1—H1N···Cl1	0.86	2.57	3.003 (3)	112

Symmetry code: (i) x, −y+1/2, z+1/2.