Crystal structure of 2-chloro-N-(3-fluoro­phen­yl)acetamide

In the title compound, C₈H₇ClFNO, the F atom is disordred over the meta positions of the benzene ring in a 0.574 (4):0.426 (4) ratio and the Cl atom is syn to the O atom [O—C—C—Cl = 5.6 (3)°]. A short intra­molecular C—H...O contact occurs. In the crystal, mol­ecules are linked into amide C(4) chains propagating in [101] by N—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• Disorder in main residue
• R factor = 0.039
• wR factor = 0.105
• Data-to-parameter ratio = 10.6

checkCIF/PLATON results

No syntax errors found



Alert level C
THETM01_ALERT_3_C  The value of sine(theta_max)/wavelength is less than 0.590
            Calculated sin(theta_max)/wavelength =    0.5846
PLAT023_ALERT_3_C Resolution (too) Low [sin(theta)/Lambda < 0.6]..      64.33 Degree
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          1 Note
              C8 H7 Cl F N O
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.585         34 Report
PLAT913_ALERT_3_C Missing # of Very Strong Reflections in FCF ....          2 Note

Alert level G
PLAT002_ALERT_2_G Number of Distance or Angle Restraints on AtSite          2 Note
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF     Please Do !
PLAT066_ALERT_1_G Predicted and Reported Tmin&Tmax Range Identical          ? Check
PLAT199_ALERT_1_G Reported _cell_measurement_temperature ..... (K)        293 Check
PLAT200_ALERT_1_G Reported   _diffrn_ambient_temperature ..... (K)        293 Check
PLAT300_ALERT_4_G Atom Site Occupancy of >F1     is Constrained at      0.574 Check
PLAT300_ALERT_4_G Atom Site Occupancy of <F1A    is Constrained at      0.426 Check
PLAT301_ALERT_3_G Main Residue  Disorder ............ Percentage =          8 Note
PLAT860_ALERT_3_G Number of Least-Squares Restraints .............          1 Note
PLAT899_ALERT_4_G SHELXL97   is Deprecated and Succeeded by SHELXL       2014 Note
PLAT909_ALERT_3_G Percentage of Observed Data at Theta(Max) still          97 %
PLAT910_ALERT_3_G Missing # of FCF Reflection(s) Below Th(Min) ...          1 Report
PLAT961_ALERT_5_G Dataset Contains no Negative Intensities .......     Please Check

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   5 ALERT level C = Check. Ensure it is not caused by an omission or oversight
  13 ALERT level G = General information/check it is not something unexpected

   3 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
   8 ALERT type 3 Indicator that the structure quality may be low
   4 ALERT type 4 Improvement, methodology, query or suggestion
   2 ALERT type 5 Informative message, check

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S1. Synthesis and crystallization

The title compound (scheme 1) was synthesized by the reaction of 2-chloro­acetyl chloride with 3-fluoro­aniline at room temperature. The reaction mixture was poured into crushed ice and the resulting solid was washed thoroughly with water, dilute hydro­chloric acid and filtered.

A small portion of the resulting compound was taken in a 10.0 ml beaker and dissolved in a 1:1 ratio of a mixture of EtOH/H₂O to obtain colourless prisms by a slow evaporation method at ~24°C.

S2. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1. The H atoms of the NH groups were located in a difference map and later restrained to N—H = 0.86 (4) Å. The other H atoms were positioned with idealized geometry using a riding model with C—H = 0.93–0.96 Å. All H atoms were refined with isotropic displacement parameters (set to 1.2 times of the Ueq of the parent atom).

Related literature

For compounds in which the meta fluorine substituent of a benzene ring exhibits positional disorder, see: Nayak et al. (2012); Sanjeevarayappa et al. (2015).

Structure description

For compounds in which the meta fluorine substituent of a benzene ring exhibits positional disorder, see: Nayak et al. (2012); Sanjeevarayappa et al. (2015).

Synthesis and crystallization

The title compound (scheme 1) was synthesized by the reaction of 2-chloro­acetyl chloride with 3-fluoro­aniline at room temperature. The reaction mixture was poured into crushed ice and the resulting solid was washed thoroughly with water, dilute hydro­chloric acid and filtered.

A small portion of the resulting compound was taken in a 10.0 ml beaker and dissolved in a 1:1 ratio of a mixture of EtOH/H₂O to obtain colourless prisms by a slow evaporation method at ~24°C.

Refinement details

Crystal data, data collection and structure refinement details are summarized in Table 1. The H atoms of the NH groups were located in a difference map and later restrained to N—H = 0.86 (4) Å. The other H atoms were positioned with idealized geometry using a riding model with C—H = 0.93–0.96 Å. All H atoms were refined with isotropic displacement parameters (set to 1.2 times of the Ueq of the parent atom).

Computing details

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT-Plus (Bruker, 2009); data reduction: SAINT-Plus (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures

	Fig. 1. A view of the molecular structure of (I), with displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. Crystal packing of (I). N—H···O hydrogen bonds are shown as dotted lines.

2-Chloro-N-(3-fluorophenyl)acetamide

Crystal data

C8H7ClFNO	Prism
Mr = 187.60	Dx = 1.551 Mg m^−3
Monoclinic, P21/n	Melting point: 385 K
Hall symbol: -P 2yn	Cu Kα radiation, λ = 1.54178 Å
a = 5.0441 (2) Å	Cell parameters from 1297 reflections
b = 18.2374 (7) Å	θ = 5.6–64.3°
c = 8.8653 (3) Å	µ = 3.95 mm^−1
β = 99.843 (1)°	T = 293 K
V = 803.53 (5) Å^3	Prism, colourless
Z = 4	0.31 × 0.24 × 0.19 mm
F(000) = 384

Data collection

Bruker APEXII diffractometer	1297 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.041
Graphite monochromator	θmax = 64.3°, θmin = 5.6°
phi and φ scans	h = −5→5
Absorption correction: multi-scan (SADABS; Bruker, 2009)	k = −21→21
Tmin = 0.368, Tmax = 0.472	l = −9→10
6045 measured reflections	1 standard reflections every 1 reflections
1304 independent reflections	intensity decay: 1%

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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.105	H atoms treated by a mixture of independent and constrained refinement
S = 1.15	w = 1/[σ^2(Fo^2) + (0.0565P)^2 + 0.4965P] where P = (Fo^2 + 2Fc^2)/3
1304 reflections	(Δ/σ)max < 0.001
123 parameters	Δρmax = 0.26 e Å^−3
1 restraint	Δρmin = −0.25 e Å^−3

Special details

Experimental. Melting point was determined by using open capillary. FT—IR Spectrum was recorded on Jasco FT—IR Spectrometer. ¹H-NMR and ¹³C-NMR spectra were recorded on Jeol-400 MHz NMR instrument using DMSO-d6 as solvent. Chemical shift values were expressed in δ (p.p.m.) relative to tetramethylsilane (TMS) as an internal reference standard. Mass spectrum of the compound was recorded on Shimadzu LC-2010EV with ESI probe. The analysis of various spectra are as follows.

IR wavenumbers (cm^-1): C=O 1674.9, C—N 1348–1060, N—H 3510–3120, C—N—C 515–409, C—Cl 850–550, C—Cl 650–515. ¹H-NMR (399.6 MHz, DMSO-d6) δ: 10.49 (s, 1H, NH), 7.57–7,55 (dd, 1H, Ar—H), 7.34–7.27 (m, 2H, Ar—H), 6.88–6.83 (m, 1H, Ar—H), 2.47 (s, 2H, –CH2-). ¹³C-NMR (100 MHz, DMSO-d6) δ: 165.41, 163.76, 140.67, 130.89, 115.54, 110.80, 106.77, 43.92. MS: Predicted Mass: 187.07; Obtained Mass 188.07 (M+1).

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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)
H1	−0.643 (5)	0.2133 (14)	0.515 (3)	0.032 (7)*
Cl1	−0.02090 (10)	0.34713 (3)	0.71994 (6)	0.0279 (2)
O1	−0.3206 (3)	0.22817 (8)	0.83631 (16)	0.0277 (4)
N1	−0.5907 (3)	0.19920 (9)	0.61148 (19)	0.0191 (4)
C1	−0.7435 (4)	0.14033 (11)	0.6567 (2)	0.0193 (4)
C7	−0.3994 (4)	0.23849 (10)	0.7000 (2)	0.0200 (4)
C6	−0.9766 (4)	0.12164 (11)	0.5553 (2)	0.0222 (5)
H6	−1.0266	0.1475	0.4645	0.027*
C2	−0.6672 (4)	0.10139 (11)	0.7913 (2)	0.0220 (5)
H2	−0.5110	0.1133	0.8589	0.026*
C4	−1.0643 (4)	0.02475 (12)	0.7255 (3)	0.0286 (5)
H4	−1.1717	−0.0135	0.7496	0.034*
C8	−0.2919 (4)	0.29966 (12)	0.6089 (2)	0.0271 (5)
H8A	−0.4359	0.3340	0.5733	0.032*
H8B	−0.2326	0.2787	0.5198	0.032*
C5	−1.1321 (4)	0.06407 (12)	0.5923 (3)	0.0271 (5)
H5	−1.2875	0.0516	0.5247	0.033*	0.574 (4)
F1A	−1.3441 (5)	0.04244 (15)	0.5018 (3)	0.0275 (9)	0.426 (4)
C3	−0.8308 (5)	0.04424 (12)	0.8222 (3)	0.0273 (5)
H3	−0.7808	0.0178	0.9122	0.033*	0.426 (4)
F1	−0.7655 (5)	0.00473 (14)	0.9442 (3)	0.0394 (8)	0.574 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0277 (3)	0.0285 (4)	0.0258 (4)	−0.00754 (18)	−0.0003 (2)	−0.00248 (19)
O1	0.0374 (9)	0.0285 (8)	0.0142 (8)	−0.0067 (6)	−0.0040 (6)	0.0009 (6)
N1	0.0232 (9)	0.0215 (8)	0.0118 (9)	−0.0014 (6)	0.0003 (6)	0.0004 (6)
C1	0.0211 (10)	0.0193 (9)	0.0185 (10)	0.0015 (8)	0.0065 (8)	−0.0045 (8)
C7	0.0231 (10)	0.0214 (10)	0.0148 (10)	0.0020 (8)	0.0017 (8)	−0.0019 (8)
C6	0.0231 (10)	0.0247 (11)	0.0187 (10)	0.0012 (8)	0.0036 (8)	−0.0030 (8)
C2	0.0234 (10)	0.0259 (10)	0.0172 (10)	0.0009 (8)	0.0046 (8)	−0.0022 (8)
C4	0.0306 (12)	0.0244 (11)	0.0348 (13)	−0.0028 (9)	0.0166 (10)	−0.0036 (9)
C8	0.0321 (12)	0.0276 (11)	0.0193 (11)	−0.0079 (9)	−0.0020 (9)	0.0015 (9)
C5	0.0229 (11)	0.0278 (11)	0.0319 (12)	−0.0040 (8)	0.0080 (9)	−0.0111 (9)
F1A	0.0209 (15)	0.0318 (17)	0.0282 (17)	−0.0062 (11)	−0.0001 (11)	−0.0039 (12)
C3	0.0348 (12)	0.0252 (11)	0.0252 (11)	0.0023 (9)	0.0143 (9)	0.0017 (9)
F1	0.0487 (16)	0.0436 (15)	0.0266 (13)	−0.0043 (11)	0.0082 (10)	0.0146 (11)

Geometric parameters (Å, º)

Cl1—C8	1.768 (2)	C2—H2	0.9300
O1—C7	1.221 (2)	C4—C5	1.374 (3)
N1—C7	1.342 (3)	C4—C3	1.380 (3)
N1—C1	1.419 (3)	C4—H4	0.9300
N1—H1	0.89 (2)	C8—H8A	0.9700
C1—C2	1.386 (3)	C8—H8B	0.9700
C1—C6	1.394 (3)	C5—F1A	1.284 (4)
C7—C8	1.530 (3)	C5—H5	0.9300
C6—C5	1.383 (3)	C3—F1	1.295 (3)
C6—H6	0.9300	C3—H3	0.9300
C2—C3	1.385 (3)
C7—N1—C1	127.59 (17)	C3—C4—H4	121.3
C7—N1—H1	118.2 (17)	C7—C8—Cl1	111.91 (14)
C1—N1—H1	113.9 (17)	C7—C8—H8A	109.2
C2—C1—C6	120.61 (19)	Cl1—C8—H8A	109.2
C2—C1—N1	123.14 (18)	C7—C8—H8B	109.2
C6—C1—N1	116.23 (18)	Cl1—C8—H8B	109.2
O1—C7—N1	125.18 (19)	H8A—C8—H8B	107.9
O1—C7—C8	123.40 (18)	F1A—C5—C4	115.8 (2)
N1—C7—C8	111.42 (16)	F1A—C5—C6	122.1 (2)
C5—C6—C1	118.9 (2)	C4—C5—C6	122.1 (2)
C5—C6—H6	120.6	C4—C5—H5	118.9
C1—C6—H6	120.6	C6—C5—H5	118.9
C3—C2—C1	117.9 (2)	F1—C3—C4	116.4 (2)
C3—C2—H2	121.0	F1—C3—C2	120.6 (2)
C1—C2—H2	121.0	C4—C3—C2	123.1 (2)
C5—C4—C3	117.4 (2)	C4—C3—H3	118.5
C5—C4—H4	121.3	C2—C3—H3	118.5
C7—N1—C1—C2	−18.4 (3)	N1—C7—C8—Cl1	−175.19 (14)
C7—N1—C1—C6	163.16 (19)	C3—C4—C5—F1A	177.0 (2)
C1—N1—C7—O1	1.9 (3)	C3—C4—C5—C6	−0.8 (3)
C1—N1—C7—C8	−177.30 (18)	C1—C6—C5—F1A	−177.6 (2)
C2—C1—C6—C5	0.7 (3)	C1—C6—C5—C4	0.0 (3)
N1—C1—C6—C5	179.19 (17)	C5—C4—C3—F1	−177.5 (2)
C6—C1—C2—C3	−0.7 (3)	C5—C4—C3—C2	0.8 (3)
N1—C1—C2—C3	−179.04 (18)	C1—C2—C3—F1	178.1 (2)
O1—C7—C8—Cl1	5.6 (3)	C1—C2—C3—C4	−0.1 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1	0.93	2.33	2.885 (3)	118
N1—H1···O1^i	0.89 (2)	1.99 (3)	2.843 (2)	160 (2)

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