2-Chloro-N-chloro­methyl-N-(2-ethyl-6-methyl­phen­yl)acetamide

Abstract

The title compound, C₁₂H₁₅Cl₂NO, was synthesized as an inter­mediate for the synthesis of the herbicide Acetochlor. The crystal structure exhibits weak inter­molecular C—H⋯O hydrogen bonds, which link the mol­ecules into zigzag chains along the b axis.

Related literature

For details of the biological activities of Acetochlor, see: Breaux (1986 ▶). For bond-length data, see: Allen et al. (1987 ▶).

Experimental

Crystal data

• C₁₂H₁₅Cl₂NO

• M _r = 260.15

• Orthorhombic,

• a = 8.3012 (17) Å

• b = 9.3787 (19) Å

• c = 16.575 (3) Å

• V = 1290.4 (5) ų

• Z = 4

• Mo Kα radiation

• μ = 0.48 mm⁻¹

• T = 296 (2) K

• 0.33 × 0.27 × 0.17 mm

Data collection

• Rigaku R-AXIS RAPID IP area-detector diffractometer

• Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ▶) T _min = 0.857, T _max = 0.922

• 20457 measured reflections

• 2403 independent reflections

• 1506 reflections with I > 2σ(I)

• R _int = 0.051

Refinement

• R[F ² > 2σ(F ²)] = 0.036

• wR(F ²) = 0.075

• S = 0.77

• 2403 reflections

• 145 parameters

• H-atom parameters constrained

• Δρ_max = 0.21 e Å⁻³

• Δρ_min = −0.14 e Å⁻³

• Absolute structure: Flack (1983 ▶), 691 Friedel pairs

• Flack parameter: 0.00 (9)

Data collection: RAPID-AUTO (Rigaku, 2004 ▶); cell refinement: RAPID-AUTO; data reduction: RAPID-AUTO; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

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
C12—H12B⋯O1i	0.97	2.43	3.375 (4)	164

Symmetry code: (i) .

supplementary crystallographic information

Comment

Acetochlor is an herbicide developed by Monsanto and Zeneca. It is a member of the class of herbicides known as chloroacetanilides. Its mode of action is elongase inhibition, and inhibition of geranylgeranyl pyrophosphate (GGPP) cyclization enzymes, part of the gibberellin pathway (Breaux, 1986). It is used to control weeds in corn, and is particularly useful as a replacement for atrazine in the case of some important weeds. The title compound, (I), was synthesized as an intermediate for the synthesis of Acetochlor. We report here the crystal structure of (I).

In (I) (Fig. 1), all bond lengths and angles are normal (Allen et al., 1987). The mean plane N1/O1/C6/C10/C11 (with largest deviation of 0.036 (2) Å) and benzene ring C1-C6 form a dihedral angle of 78.0 (3)°. The crystal packing exhibits weak intermolecular C–H···O hydrogen bonds (Table 1), which link the molecules into zigzag chains along b axis.

Experimental

The xylene solution containing N-methylene-2'-methyl-6'-ethyl-aniline was introduced into a mixture of 1.2 g (0.01 mol) of chloroacetyl chloride and 2 g xylene at 293 K to 313 K under continuous stirring. After about 15 minutes of stirring, 2.5 g of dry ethanol were introduced into mixture at 293 K to 313 K. The reaction mixture was stirred for 5 h, whereupon accoholysis proceeded. At the end of the reaction, 6 g of water were introduced into the mixture, and the phases were separated. The upper organic phase was washed acid-free with about 10 g of water,and the xylene solution, containing about 2.5 g of the desired end product, was separated. Single crystals suitable for X-ray measurements were obtained by recrystallization from ethanol and dichloromethane at room temperature.

Refinement

H atoms were positioned geometrically (C—H = 0.93–0.97 Å), and refined using a riding model, with U_iso(H) = 1.2 (1.5 for methyl groups) times U_eq(C).

Figures

Fig. 1.

The molecular structure of (I), with atom labels and 30% probability displacement ellipsoids for non-H atoms.

Crystal data

C12H15Cl2NO	F000 = 544
Mr = 260.15	Dx = 1.339 Mg m−3
Orthorhombic, P212121	Mo Kα radiation λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 987 reflections
a = 8.3012 (17) Å	θ = 2.2–27.5º
b = 9.3787 (19) Å	µ = 0.48 mm−1
c = 16.575 (3) Å	T = 296 (2) K
V = 1290.4 (5) Å3	Plate, colorless
Z = 4	0.33 × 0.27 × 0.17 mm

Data collection

Rigaku R-AXIS RAPID IP area-detector diffractometer	2403 independent reflections
Radiation source: rotating anode	1506 reflections with I > 2σ(I)
Monochromator: graphite	Rint = 0.051
T = 296(2) K	θmax = 25.5º
ω scans at fixed χ = 45°	θmin = 2.5º
Absorption correction: multi-scan(ABSCOR; Higashi, 1995)	h = −10→10
Tmin = 0.857, Tmax = 0.923	k = −11→11
20457 measured reflections	l = −19→20

Refinement

Refinement on F2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F2 > 2σ(F2)] = 0.037	w = 1/[σ2(Fo2) + (0.0172P)2] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.075	(Δ/σ)max = 0.001
S = 0.77	Δρmax = 0.21 e Å−3
2403 reflections	Δρmin = −0.14 e Å−3
145 parameters	Extinction correction: none
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 691 Friedel pairs
Secondary atom site location: difference Fourier map	Flack parameter: 0.00 (9)

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
Cl1	0.86248 (17)	1.10317 (8)	0.59963 (5)	0.0986 (4)
Cl2	0.61827 (15)	0.78116 (9)	0.88510 (5)	0.0859 (3)
O1	0.6020 (3)	0.9889 (2)	0.75349 (11)	0.0616 (6)
N1	0.7273 (3)	0.8602 (2)	0.65690 (13)	0.0444 (6)
C1	0.7314 (4)	0.6328 (3)	0.58464 (17)	0.0495 (7)
C2	0.8149 (4)	0.5122 (3)	0.56042 (17)	0.0605 (9)
H2A	0.7634	0.4437	0.5291	0.073*
C3	0.9741 (5)	0.4929 (3)	0.58248 (18)	0.0611 (9)
H3A	1.0287	0.4116	0.5656	0.073*
C4	1.0523 (4)	0.5913 (3)	0.62872 (17)	0.0558 (8)
H4A	1.1592	0.5761	0.6432	0.067*
C5	0.9737 (4)	0.7147 (3)	0.65459 (16)	0.0468 (7)
C6	0.8129 (3)	0.7325 (3)	0.63222 (14)	0.0417 (7)
C7	0.5558 (4)	0.6500 (4)	0.56248 (19)	0.0717 (10)
H7A	0.5165	0.7390	0.5832	0.108*
H7B	0.4947	0.5730	0.5853	0.108*
H7C	0.5447	0.6488	0.5048	0.108*
C8	1.0590 (4)	0.8198 (4)	0.7098 (2)	0.0742 (11)
H8A	0.9981	0.9080	0.7100	0.089*
H8B	1.0563	0.7819	0.7643	0.089*
C10	0.7080 (4)	0.9714 (3)	0.59945 (18)	0.0631 (9)
H10A	0.6057	1.0181	0.6094	0.076*
H10B	0.7029	0.9292	0.5461	0.076*
C11	0.6641 (3)	0.8780 (3)	0.73246 (16)	0.0456 (7)
C12	0.6724 (4)	0.7457 (3)	0.78494 (15)	0.0586 (8)
H12A	0.7812	0.7080	0.7837	0.070*
H12B	0.6009	0.6736	0.7631	0.070*
C9	1.2274 (5)	0.8537 (5)	0.6897 (3)	0.145 (2)
H9A	1.2684	0.9222	0.7275	0.217*
H9B	1.2325	0.8926	0.6362	0.217*
H9C	1.2911	0.7684	0.6923	0.217*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Cl1	0.1649 (10)	0.0562 (5)	0.0746 (6)	−0.0264 (7)	0.0055 (7)	0.0077 (4)
Cl2	0.1260 (8)	0.0752 (5)	0.0565 (5)	−0.0120 (6)	0.0273 (6)	−0.0026 (4)
O1	0.0704 (15)	0.0524 (12)	0.0621 (12)	0.0181 (13)	0.0044 (12)	−0.0097 (10)
N1	0.0505 (15)	0.0416 (13)	0.0412 (13)	0.0070 (12)	−0.0038 (11)	−0.0019 (11)
C1	0.060 (2)	0.0421 (16)	0.0461 (16)	−0.0048 (16)	0.0026 (15)	−0.0013 (14)
C2	0.086 (3)	0.0459 (18)	0.0501 (17)	−0.0116 (19)	0.0115 (18)	−0.0087 (14)
C3	0.078 (3)	0.0427 (17)	0.063 (2)	0.0139 (19)	0.019 (2)	0.0035 (16)
C4	0.051 (2)	0.0562 (18)	0.0601 (19)	0.0094 (17)	0.0075 (16)	0.0121 (16)
C5	0.052 (2)	0.0452 (16)	0.0431 (15)	−0.0001 (15)	0.0030 (14)	0.0026 (14)
C6	0.0493 (19)	0.0379 (15)	0.0380 (14)	0.0062 (14)	0.0014 (13)	0.0006 (13)
C7	0.065 (2)	0.078 (2)	0.072 (2)	−0.0091 (19)	−0.0055 (19)	−0.0107 (18)
C8	0.063 (3)	0.077 (2)	0.083 (3)	0.0028 (19)	−0.023 (2)	−0.002 (2)
C10	0.084 (2)	0.0505 (17)	0.0543 (18)	0.0211 (17)	−0.0101 (18)	−0.0019 (15)
C11	0.0418 (18)	0.0460 (17)	0.0491 (16)	−0.0023 (15)	−0.0055 (14)	−0.0043 (14)
C12	0.069 (2)	0.0537 (17)	0.0531 (17)	−0.0057 (17)	0.0113 (16)	−0.0039 (15)
C9	0.058 (3)	0.104 (3)	0.272 (7)	−0.018 (3)	0.017 (4)	−0.060 (4)

Geometric parameters (Å, °)

Cl1—C10	1.781 (3)	C5—C8	1.521 (4)
Cl2—C12	1.752 (3)	C7—H7A	0.9600
O1—C11	1.212 (3)	C7—H7B	0.9600
N1—C11	1.368 (3)	C7—H7C	0.9600
N1—C10	1.421 (3)	C8—C9	1.472 (5)
N1—C6	1.451 (3)	C8—H8A	0.9700
C1—C2	1.387 (4)	C8—H8B	0.9700
C1—C6	1.398 (4)	C10—H10A	0.9700
C1—C7	1.511 (4)	C10—H10B	0.9700
C2—C3	1.384 (4)	C11—C12	1.517 (4)
C2—H2A	0.9300	C12—H12A	0.9700
C3—C4	1.364 (4)	C12—H12B	0.9700
C3—H3A	0.9300	C9—H9A	0.9600
C4—C5	1.396 (4)	C9—H9B	0.9600
C4—H4A	0.9300	C9—H9C	0.9600
C5—C6	1.395 (4)
C11—N1—C10	118.7 (2)	C9—C8—C5	116.5 (3)
C11—N1—C6	123.1 (2)	C9—C8—H8A	108.2
C10—N1—C6	118.2 (2)	C5—C8—H8A	108.2
C2—C1—C6	117.8 (3)	C9—C8—H8B	108.2
C2—C1—C7	119.9 (3)	C5—C8—H8B	108.2
C6—C1—C7	122.2 (3)	H8A—C8—H8B	107.3
C3—C2—C1	120.5 (3)	N1—C10—Cl1	115.3 (2)
C3—C2—H2A	119.7	N1—C10—H10A	108.5
C1—C2—H2A	119.7	Cl1—C10—H10A	108.5
C4—C3—C2	121.0 (3)	N1—C10—H10B	108.5
C4—C3—H3A	119.5	Cl1—C10—H10B	108.5
C2—C3—H3A	119.5	H10A—C10—H10B	107.5
C3—C4—C5	120.7 (3)	O1—C11—N1	122.1 (2)
C3—C4—H4A	119.6	O1—C11—C12	123.8 (3)
C5—C4—H4A	119.6	N1—C11—C12	114.1 (2)
C6—C5—C4	117.7 (3)	C11—C12—Cl2	112.13 (19)
C6—C5—C8	121.9 (3)	C11—C12—H12A	109.2
C4—C5—C8	120.3 (3)	Cl2—C12—H12A	109.2
C5—C6—C1	122.2 (3)	C11—C12—H12B	109.2
C5—C6—N1	119.5 (3)	Cl2—C12—H12B	109.2
C1—C6—N1	118.3 (2)	H12A—C12—H12B	107.9
C1—C7—H7A	109.5	C8—C9—H9A	109.5
C1—C7—H7B	109.5	C8—C9—H9B	109.5
H7A—C7—H7B	109.5	H9A—C9—H9B	109.5
C1—C7—H7C	109.5	C8—C9—H9C	109.5
H7A—C7—H7C	109.5	H9A—C9—H9C	109.5
H7B—C7—H7C	109.5	H9B—C9—H9C	109.5
C6—C1—C2—C3	−0.5 (4)	C11—N1—C6—C5	−79.7 (3)
C7—C1—C2—C3	−177.9 (3)	C10—N1—C6—C5	100.6 (3)
C1—C2—C3—C4	0.3 (5)	C11—N1—C6—C1	102.0 (3)
C2—C3—C4—C5	−0.4 (4)	C10—N1—C6—C1	−77.7 (3)
C3—C4—C5—C6	0.6 (4)	C6—C5—C8—C9	−140.5 (4)
C3—C4—C5—C8	176.7 (3)	C4—C5—C8—C9	43.6 (5)
C4—C5—C6—C1	−0.9 (4)	C11—N1—C10—Cl1	88.9 (3)
C8—C5—C6—C1	−176.9 (3)	C6—N1—C10—Cl1	−91.4 (3)
C4—C5—C6—N1	−179.1 (2)	C10—N1—C11—O1	−5.1 (4)
C8—C5—C6—N1	4.9 (4)	C6—N1—C11—O1	175.2 (3)
C2—C1—C6—C5	0.8 (4)	C10—N1—C11—C12	172.3 (3)
C7—C1—C6—C5	178.1 (3)	C6—N1—C11—C12	−7.4 (4)
C2—C1—C6—N1	179.1 (2)	O1—C11—C12—Cl2	−11.6 (4)
C7—C1—C6—N1	−3.6 (4)	N1—C11—C12—Cl2	171.1 (2)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
C12—H12B···O1i	0.97	2.43	3.375 (4)	164

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