2,2,2-Trimethyl-N-(2,4,5-trichloro­phen­yl)acetamide

In the structure of the title compound, C₁₁H₁₂Cl₃NO, the N-H bond is syn to the ortho-chloro and anti to the meta-chloro substituents. There is an intra­molecular hydrogen bond between the NH hydrogen and the ortho Cl atom.

Key indicators

• Single-crystal X-ray study
• T = 299 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.038
• wR factor = 0.107
• Data-to-parameter ratio = 12.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT431_ALERT_2_C Short Inter HL..A Contact  Cl14   ..  O5      ..       3.21 Ang.

   0 ALERT level A = In general: serious problem
   0 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
   0 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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Computing details

Data collection: CAD-4 EXPRESS (Nonius, 1996); cell refinement: CAD-4 EXPRESS; 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: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.

2,2,2-Trimethyl-N-(2,4,5-trichlorophenyl)acetamide

Crystal data

C11H12Cl3NO	F(000) = 576
Mr = 280.57	Dx = 1.478 Mg m^−3
Orthorhombic, Pnma	Cu Kα radiation, λ = 1.54180 Å
Hall symbol: -P 2ac 2n	Cell parameters from 25 reflections
a = 18.831 (2) Å	θ = 9.4–23.3°
b = 6.9610 (7) Å	µ = 6.41 mm^−1
c = 9.6196 (4) Å	T = 299 K
V = 1260.96 (19) Å^3	Prism, colourless
Z = 4	0.35 × 0.25 × 0.25 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	Rint = 0.065
Radiation source: fine-focus sealed tube	θmax = 66.9°, θmin = 4.7°
Graphite monochromator	h = −22→22
ω/2θ scans	k = 0→8
2408 measured reflections	l = −11→0
1225 independent reflections	3 standard reflections every 120 min
1090 reflections with I > 2σ(I)	intensity decay: 3.5%

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)] = 0.038	H-atom parameters constrained
wR(F^2) = 0.107	w = 1/[σ^2(Fo^2) + (0.0568P)^2 + 0.2968P] where P = (Fo^2 + 2Fc^2)/3
S = 1.10	(Δ/σ)max = 0.009
1225 reflections	Δρmax = 0.41 e Å^−3
95 parameters	Δρmin = −0.28 e Å^−3
4 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: 0.0190 (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
C1	0.17347 (13)	0.0712 (4)	0.4224 (3)	0.0663 (7)
H1A	0.2016	−0.0414	0.4055	0.080*
H1B	0.1324	0.0693	0.3633	0.080*
H1C	0.1587	0.0731	0.5179	0.080*
C2	0.2402 (2)	0.2500	0.2374 (3)	0.0742 (12)
H2A	0.1998	0.2500	0.1791	0.089*
H2B	0.26801	0.36260	0.21851	0.089*
C3	0.21746 (15)	0.2500	0.3914 (3)	0.0461 (7)
C4	0.27977 (14)	0.2500	0.4928 (3)	0.0415 (6)
C7	0.41182 (13)	0.2500	0.5015 (2)	0.0352 (6)
C8	0.42059 (13)	0.2500	0.6450 (3)	0.0364 (6)
H8	0.3810	0.2500	0.7027	0.044*
C9	0.48795 (14)	0.2500	0.7026 (3)	0.0370 (6)
C10	0.54779 (13)	0.2500	0.6185 (3)	0.0402 (6)
C11	0.53956 (14)	0.2500	0.4766 (3)	0.0436 (6)
H11	0.5793	0.2500	0.4194	0.052*
C12	0.47278 (14)	0.2500	0.4190 (3)	0.0387 (6)
N6	0.34534 (12)	0.2500	0.4360 (2)	0.0435 (6)
H6N	0.3465	0.2500	0.3466	0.052*
O5	0.27073 (11)	0.2500	0.6174 (2)	0.0751 (9)
Cl13	0.46482 (4)	0.2500	0.23926 (7)	0.0569 (3)
Cl14	0.63235 (3)	0.2500	0.68848 (9)	0.0606 (3)
Cl15	0.49593 (4)	0.2500	0.88142 (7)	0.0545 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0567 (13)	0.0697 (15)	0.0725 (14)	−0.0139 (11)	−0.0137 (12)	−0.0051 (12)
C2	0.0534 (19)	0.130 (4)	0.0395 (16)	0.000	−0.0126 (15)	0.000
C3	0.0344 (13)	0.0640 (18)	0.0400 (14)	0.000	−0.0073 (11)	0.000
C4	0.0360 (13)	0.0551 (15)	0.0334 (13)	0.000	−0.0009 (11)	0.000
C7	0.0327 (12)	0.0411 (12)	0.0318 (12)	0.000	0.0025 (10)	0.000
C8	0.0304 (11)	0.0468 (13)	0.0318 (12)	0.000	0.0059 (10)	0.000
C9	0.0351 (12)	0.0436 (13)	0.0323 (12)	0.000	−0.0003 (10)	0.000
C10	0.0301 (12)	0.0446 (14)	0.0459 (15)	0.000	0.0013 (11)	0.000
C11	0.0339 (12)	0.0493 (14)	0.0477 (15)	0.000	0.0136 (12)	0.000
C12	0.0410 (13)	0.0424 (13)	0.0328 (12)	0.000	0.0086 (11)	0.000
N6	0.0340 (10)	0.0690 (15)	0.0275 (10)	0.000	0.0001 (9)	0.000
O5	0.0349 (10)	0.155 (3)	0.0348 (11)	0.000	−0.0005 (8)	0.000
Cl13	0.0631 (5)	0.0771 (5)	0.0306 (4)	0.000	0.0124 (3)	0.000
Cl14	0.0299 (4)	0.0803 (6)	0.0717 (6)	0.000	−0.0048 (3)	0.000
Cl15	0.0477 (5)	0.0818 (6)	0.0339 (4)	0.000	−0.0062 (3)	0.000

Geometric parameters (Å, º)

C1—C3	1.524 (3)	C7—C12	1.396 (4)
C1—H1A	0.9600	C7—N6	1.401 (3)
C1—H1B	0.9600	C8—C9	1.384 (4)
C1—H1C	0.9600	C8—H8	0.9300
C2—C3	1.542 (4)	C9—C10	1.387 (4)
C2—H2A	0.96	C9—Cl15	1.727 (3)
C2—H2B	0.96	C10—C11	1.373 (4)
C3—C1^i	1.524 (3)	C10—Cl14	1.729 (3)
C3—C4	1.526 (4)	C11—C12	1.375 (4)
C4—O5	1.211 (4)	C11—H11	0.9300
C4—N6	1.350 (4)	C12—Cl13	1.735 (3)
C7—C8	1.391 (4)	N6—H6N	0.8600
C3—C1—H1A	109.5	C12—C7—N6	118.6 (2)
C3—C1—H1B	109.5	C9—C8—C7	120.4 (2)
H1A—C1—H1B	109.5	C9—C8—H8	119.8
C3—C1—H1C	109.5	C7—C8—H8	119.8
H1A—C1—H1C	109.5	C8—C9—C10	120.8 (2)
H1B—C1—H1C	109.5	C8—C9—Cl15	118.6 (2)
C3—C2—H2A	109.5	C10—C9—Cl15	120.7 (2)
C3—C2—H2B	109.5	C11—C10—C9	119.2 (2)
H2A—C2—H2B	109.5	C11—C10—Cl14	119.4 (2)
C1—C3—C1^i	109.5 (3)	C9—C10—Cl14	121.4 (2)
C1—C3—C4	107.01 (17)	C10—C11—C12	120.3 (3)
C1^i—C3—C4	107.01 (17)	C10—C11—H11	119.9
C1—C3—C2	109.82 (18)	C12—C11—H11	119.9
C1^i—C3—C2	109.82 (18)	C11—C12—C7	121.5 (3)
C4—C3—C2	113.6 (2)	C11—C12—Cl13	118.8 (2)
O5—C4—N6	122.0 (3)	C7—C12—Cl13	119.7 (2)
O5—C4—C3	121.7 (3)	C4—N6—C7	129.4 (2)
N6—C4—C3	116.4 (2)	C4—N6—H6N	115.3
C8—C7—C12	117.8 (2)	C7—N6—H6N	115.3
C8—C7—N6	123.5 (2)
C1—C3—C4—O5	−58.62 (17)	Cl15—C9—C10—Cl14	0.0
C1^i—C3—C4—O5	58.62 (17)	C9—C10—C11—C12	0.0
C2—C3—C4—O5	180.0	Cl14—C10—C11—C12	180.0
C1—C3—C4—N6	121.38 (17)	C10—C11—C12—C7	0.0
C1^i—C3—C4—N6	−121.38 (17)	C10—C11—C12—Cl13	180.0
C2—C3—C4—N6	0.0	C8—C7—C12—C11	0.0
C12—C7—C8—C9	0.0	N6—C7—C12—C11	180.0
N6—C7—C8—C9	180.0	C8—C7—C12—Cl13	180.0
C7—C8—C9—C10	0.0	N6—C7—C12—Cl13	0.0
C7—C8—C9—Cl15	180.0	O5—C4—N6—C7	0.0
C8—C9—C10—C11	0.0	C3—C4—N6—C7	180.0
Cl15—C9—C10—C11	180.0	C8—C7—N6—C4	0.0
C8—C9—C10—Cl14	180.0	C12—C7—N6—C4	180.0

Symmetry code: (i) x, −y+1/2, z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N6—H6N···Cl13	0.86	2.46	2.940 (2)	116