2,2,2-Trichloro-N-(2-methyl­phen­yl)acetamide

The conformation of the N—H bond in the structure of the title compound (2MPTCA), C₉H₈Cl₃NO, is syn to the ortho-methyl substituent, in contrast to the anti conformation observed for the side-chain-unsubstituted N-(2-methyl­phen­yl)acetamide, with somewhat slightly different bond parameters. Mol­ecules of 2MPTCA are linked into a chain through N—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 304 K
• Mean [sigma](C-C) = 0.007 Å
• Disorder in main residue
• R factor = 0.044
• wR factor = 0.131
• Data-to-parameter ratio = 10.6

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT241_ALERT_2_B Check High      Ueq as Compared to Neighbors for       Cl1B
PLAT241_ALERT_2_B Check High      Ueq as Compared to Neighbors for       Cl3B
PLAT242_ALERT_2_B Check Low       Ueq as Compared to Neighbors for         C4

Alert level C
PLAT153_ALERT_1_C The su's on the Cell Axes are Equal (x 100000) .        200 Ang.
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for       Cl2B
PLAT301_ALERT_3_C Main Residue  Disorder .........................      18.00 Perc.
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          7
PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety        C14

Alert level G
REFLT03_ALERT_4_G  WARNING: Large fraction of Friedel related reflns may
                     be needed to determine absolute structure
           From the CIF: _diffrn_reflns_theta_max           26.00
           From the CIF: _reflns_number_total               1683
           Count of symmetry unique reflns         1294
           Completeness (_total/calc)            130.06%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       389
           Fraction of Friedel pairs measured     0.301
           Are heavy atom types Z>Si present        yes

   0 ALERT level A = In general: serious problem
   3 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   4 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: STADI4 (Stoe & Cie, 1987); cell refinement: STADI4; data reduction: REDU4 (Stoe & Cie, 1987); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXL97.

2,2,2-Trichloro-N-(2-methylphenyl)acetamide

Crystal data

C9H8Cl3NO	F(000) = 512
Mr = 252.51	Dx = 1.495 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 67 reflections
a = 10.150 (2) Å	θ = 14.1–57.6°
b = 10.216 (2) Å	µ = 0.78 mm^−1
c = 10.817 (2) Å	T = 304 K
V = 1121.7 (4) Å^3	Needle, grey
Z = 4	0.55 × 0.16 × 0.13 mm

Data collection

Stoe Stadi4 four-circle diffractometer	1257 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.019
Graphite monochromator	θmax = 26.0°, θmin = 2.7°
profile fitted scan 2θ/ω 1/1	h = −1→12
Absorption correction: analytical (Clark & Reid, 1995)	k = −1→12
Tmin = 0.675, Tmax = 0.907	l = −13→2
1893 measured reflections	3 standard reflections every 120 min
1683 independent reflections	intensity decay: none

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F^2 > 2σ(F^2)] = 0.044	w = 1/[σ^2(Fo^2) + (0.0528P)^2 + 0.4591P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.131	(Δ/σ)max = 0.006
S = 1.04	Δρmax = 0.18 e Å^−3
1683 reflections	Δρmin = −0.24 e Å^−3
159 parameters	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
2 restraints	Extinction coefficient: 0.011 (3)
Primary atom site location: structure-invariant direct methods	Absolute structure: (Flack, 1983), 396 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: −0.19 (14)

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	Occ. (<1)
Cl1B	0.7851 (8)	0.7197 (11)	0.6433 (10)	0.109 (4)	0.5
Cl1A	0.7848 (9)	0.7091 (9)	0.6326 (7)	0.075 (2)	0.5
Cl2B	0.6113 (6)	0.8712 (5)	0.5020 (5)	0.1108 (17)	0.5
Cl2A	0.6533 (5)	0.9398 (5)	0.5373 (6)	0.1173 (19)	0.5
Cl3B	0.7423 (5)	0.9867 (5)	0.7044 (6)	0.134 (2)	0.5
Cl3A	0.7733 (5)	0.9409 (5)	0.7775 (5)	0.1021 (16)	0.5
C4	0.6782 (4)	0.8440 (4)	0.6620 (5)	0.0647 (12)
C5	0.5511 (4)	0.8003 (4)	0.7264 (4)	0.0499 (9)
C8	0.3575 (4)	0.8760 (4)	0.8369 (4)	0.0487 (10)
C9	0.2553 (4)	0.8219 (4)	0.7706 (5)	0.0631 (11)
H9	0.2682	0.7955	0.6892	0.076*
C10	0.1325 (5)	0.8068 (5)	0.8261 (6)	0.0772 (15)
H10	0.0626	0.7716	0.7815	0.093*
C11	0.1151 (5)	0.8437 (5)	0.9460 (7)	0.0821 (16)
H11	0.0336	0.8324	0.9838	0.099*
C12	0.2175 (6)	0.8973 (5)	1.0105 (5)	0.0717 (13)
H12	0.2037	0.9229	1.092	0.086*
C13	0.3400 (4)	0.9147 (4)	0.9593 (4)	0.0539 (10)
C14	0.4502 (6)	0.9774 (5)	1.0315 (5)	0.0725 (13)
H14A	0.5278	0.9816	0.981	0.109*
H14B	0.4683	0.9263	1.104	0.109*
H14C	0.4248	1.0643	1.0555	0.109*
O6	0.5208 (3)	0.6856 (3)	0.7256 (3)	0.0674 (9)
N7	0.4819 (3)	0.8955 (3)	0.7789 (4)	0.0534 (9)
H7	0.507 (5)	0.967 (5)	0.773 (5)	0.064*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1B	0.051 (3)	0.079 (5)	0.198 (9)	0.018 (3)	0.020 (4)	−0.015 (5)
Cl1A	0.080 (4)	0.055 (3)	0.091 (3)	0.005 (3)	0.018 (3)	−0.020 (2)
Cl2B	0.127 (4)	0.125 (4)	0.080 (2)	0.010 (3)	0.030 (3)	0.033 (3)
Cl2A	0.104 (3)	0.130 (4)	0.117 (4)	0.022 (3)	0.029 (3)	0.066 (4)
Cl3B	0.105 (4)	0.085 (3)	0.213 (6)	−0.058 (3)	0.091 (4)	−0.077 (4)
Cl3A	0.0676 (17)	0.103 (4)	0.136 (3)	−0.028 (2)	0.007 (2)	−0.059 (3)
C4	0.066 (2)	0.043 (2)	0.085 (3)	−0.001 (2)	0.022 (2)	−0.011 (2)
C5	0.0547 (19)	0.039 (2)	0.056 (2)	−0.0026 (17)	−0.0010 (19)	−0.0032 (19)
C8	0.051 (2)	0.035 (2)	0.060 (2)	0.0052 (16)	0.0030 (19)	0.0042 (18)
C9	0.065 (2)	0.055 (2)	0.070 (3)	−0.005 (2)	−0.003 (2)	0.004 (2)
C10	0.056 (2)	0.065 (3)	0.111 (4)	−0.005 (2)	−0.007 (3)	0.009 (3)
C11	0.069 (3)	0.061 (3)	0.116 (5)	0.004 (3)	0.036 (3)	0.015 (3)
C12	0.086 (3)	0.051 (2)	0.078 (3)	0.010 (3)	0.025 (3)	0.006 (2)
C13	0.061 (2)	0.038 (2)	0.064 (3)	0.0070 (18)	0.010 (2)	0.005 (2)
C14	0.095 (3)	0.059 (3)	0.064 (3)	0.006 (3)	−0.007 (3)	−0.008 (2)
O6	0.0702 (17)	0.0348 (16)	0.097 (2)	−0.0035 (13)	0.0144 (18)	−0.0050 (16)
N7	0.0561 (18)	0.0314 (15)	0.073 (2)	−0.0050 (15)	0.0114 (19)	−0.0054 (19)

Geometric parameters (Å, º)

Cl1A—C4	1.781 (10)	C9—H9	0.93
Cl2A—C4	1.685 (7)	C10—C11	1.361 (9)
Cl3A—C4	1.864 (7)	C10—H10	0.93
Cl1B—C4	1.683 (10)	C11—C12	1.367 (8)
Cl2B—C4	1.880 (7)	C11—H11	0.93
Cl3B—C4	1.660 (6)	C12—C13	1.372 (6)
C4—C5	1.533 (6)	C12—H12	0.93
C5—O6	1.212 (5)	C13—C14	1.507 (7)
C5—N7	1.328 (5)	C14—H14A	0.96
C8—C9	1.377 (6)	C14—H14B	0.96
C8—C13	1.393 (6)	C14—H14C	0.96
C8—N7	1.424 (5)	N7—H7	0.78 (5)
C9—C10	1.392 (7)
Cl1A—C4—Cl3A	102.5 (4)	C11—C10—C9	119.7 (5)
Cl2A—C4—Cl3A	107.8 (4)	C11—C10—H10	120.1
Cl2A—C4—Cl1A	113.4 (4)	C12—C11—H11	120
Cl1B—C4—Cl2B	103.5 (5)	C11—C12—C13	122.3 (5)
Cl3B—C4—Cl2B	105.5 (4)	C11—C12—H12	118.8
C5—C4—Cl3B	117.4 (4)	C12—C13—C8	117.5 (4)
C5—C4—Cl2A	114.0 (3)	C12—C13—C14	121.2 (4)
C5—C4—Cl1A	111.5 (4)	C13—C8—N7	119.5 (4)
C5—C4—Cl3A	106.6 (3)	C13—C12—H12	118.8
O6—C5—C4	119.5 (4)	C13—C14—H14A	109.5
O6—C5—N7	125.2 (4)	C13—C14—H14B	109.5
N7—C5—C4	115.2 (3)	H14A—C14—H14B	109.5
C8—C9—C10	119.6 (5)	C13—C14—H14C	109.5
C8—C9—H9	120.2	H14A—C14—H14C	109.5
C8—C13—C14	121.2 (4)	H14B—C14—H14C	109.5
C9—C8—C13	120.9 (4)	C5—N7—C8	123.7 (3)
C9—C8—N7	119.6 (4)	C5—N7—H7	118 (4)
C9—C10—H10	120.1	C8—N7—H7	118 (4)
C10—C11—C12	119.9 (5)	C5—C4—Cl1B	112.1 (5)
C10—C11—H11	120	C5—C4—Cl2B	99.0 (3)
C10—C9—H9	120.2
Cl1A—C4—C5—O6	−16.5 (6)	C8—C9—C10—C11	−1.1 (7)
Cl2A—C4—C5—O6	113.6 (5)	C9—C10—C11—C12	1.1 (8)
Cl3A—C4—C5—O6	−127.6 (4)	C10—C11—C12—C13	−0.7 (8)
Cl1A—C4—C5—N7	163.9 (4)	C11—C12—C13—C8	0.3 (7)
Cl2A—C4—C5—N7	−66.0 (5)	C11—C12—C13—C14	178.4 (5)
Cl3A—C4—C5—N7	52.8 (4)	C9—C8—C13—C12	−0.3 (6)
Cl1B—C4—C5—O6	−20.8 (7)	N7—C8—C13—C12	178.3 (4)
Cl1B—C4—C5—N7	159.6 (5)	C9—C8—C13—C14	−178.3 (4)
Cl2B—C4—C5—N7	−91.8 (4)	N7—C8—C13—C14	0.3 (6)
Cl2B—C4—C5—O6	87.8 (4)	O6—C5—N7—C8	−3.3 (7)
Cl3B—C4—C5—N7	21.0 (6)	C4—C5—N7—C8	176.2 (4)
Cl3B—C4—C5—O6	−159.4 (5)	C9—C8—N7—C5	−57.0 (6)
C13—C8—C9—C10	0.7 (6)	C13—C8—N7—C5	124.4 (4)
N7—C8—C9—C10	−177.9 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N7—H7···O6^i	0.78 (5)	2.25 (5)	2.964 (4)	153 (5)

Symmetry code: (i) −x+1, y+1/2, −z+3/2.