2-(4-Bromo­phen­yl)-N-(3,4-di­fluoro­phen­yl)acetamide

In the title compound, C₁₄H₁₀BrF₂NO, the dihedral angle between the mean planes of the 4-bromo­phenyl and 3,4-di­fluoro­phenyl rings is 66.4 (1)°. These two planes are twisted by 40.0 (5) and 86.3 (2)°, respectively, from that of the acetamide group. In the crystal, N—H...O hydrogen bonds and weak C—H...O and C—H...F inter­actions form infinite chains along [100].

Key indicators

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.009 Å
• R factor = 0.041
• wR factor = 0.106
• Data-to-parameter ratio = 13.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT341_ALERT_3_C Low Bond Precision on  C-C Bonds ...............     0.0093 Ang
PLAT480_ALERT_4_C Long H...A H-Bond Reported H7     ..  O1      ..       2.63 Ang.
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600         10

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF          ?
PLAT007_ALERT_5_G Note: Number of Unrefined Donor-H Atoms ........          1
PLAT434_ALERT_2_G Short Inter HL..HL Contact  Br1    ..  Br1     .       3.58 Ang.
PLAT434_ALERT_2_G Short Inter HL..HL Contact  Br1    ..  Br1     .       3.58 Ang.
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600          5
PLAT961_ALERT_5_G Dataset Contains no Negative Intensities .......          !

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

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


checkCIF publication errors

Alert level A
PUBL024_ALERT_1_A The number of authors is greater than 5.
              Please specify the role of each of the co-authors
              for your paper.

Author Response: Each of the authors presented on this paper made significant and appropriate contributions to this submission

   1 ALERT level A = Data missing that is essential or data in wrong format
   0 ALERT level G = General alerts. Data that may be required is missing

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S1. Comment

N-Substituted 2-arylacetamides are very interesting compounds because of their structural similarity to the lateral chain of natural benzylpenicillin (Mijin et al., 2006, 2008). Amides are also used as ligands due to their excellent coordination abilities (Wu et al., 2008, 2010). Crystal structures of some acetamide derivatives viz., N-(3-chloro-4-fluorophenyl)-2-(naphthalen-1-yl)acetamide (Praveen et al., 2011a), N-(4-chloro-1,3-benzothiazol-2-yl)-2- (3-methylphenyl)acetamide monohydrate (Praveen et al., 2011b), N-(3-chloro-4-fluorophenyl)-2,2-diphenylacetamide (Praveen et al., 2011c) and N-(4,6-dimethoxypyrimidin-2-yl)-2-(3-methylphenyl)acetamide (Praveen et al., 2012) have been reported. In view of the importance of amides, we report here in the crystal structure of the title compound, C₁₄H₁₀BrF₂NO, (I).

In (I) the dihedral angle between the mean planes of the 4-bromophenyl and 3,4-difluorophenyl rings is 66.4 (1)° (Fig. 1). These two planes are twisted by 40.0 (5)° and 86.3 (2)°, respectively, from that of the acetamide group. Bond lengths are in normal ranges (Allen et al., 1987). In the crystal, N—H···O hydrogen bonds and weak C—H···O and C—H···F intermolecular interactions are observed forming a infinite chains along (100) and contribute to packing stability (Fig. 2).

Related literature

For the structural similarity of N-substituted 2-arylacetamides to the lateral chain of natural benzylpenicillin, see: Mijin & Marinkovic (2006); Mijin et al. (2008). For the coordination abilities of amides, see: Wu et al. (2008, 2010). For related structures, see: Praveen et al. (2011a,b,c, 2012). For standard bond lengths, see: Allen et al. (1987).

S2. Experimental

4-bromophenylacetic acid (0.213 g, 1 mmol), 3,4-difluoro aniline (0.129 g, 1 mmol) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (1.0 g, 0.01 mol) were dissolved in dichloromethane (20 mL) (Fig. 3). The mixture was stirred in presence of triethylamine at 273 K for about 3 h. The contents were poured into 100 ml of ice-cold aqueous hydrochloric acid with stirring, which was extracted thrice with dichloromethane. The organic layer was washed with saturated NaHCO₃ solution and brine solution, dried and concentrated under reduced pressure to give the title compound (I). Single crystals were grown from methylene chloride by the slow evaporation method (m.p.: 423–425 K).

S3. Refinement

All of the H atoms were placed in their calculated positions and then refined using the riding model with Atom—H lengths of 0.95Å (CH), 0.99Å (CH₂) or 0.88° (NH). Isotropic displacement parameters for these atoms were set to 1.2 (CH, CH₂, NH) times U_eq of the parent atom.

Computing details

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis RED (Agilent, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2012 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Figures

	Fig. 1. Molecular structure of the title compound showing the atom labeling scheme and 30% probability displacement ellipsoids.
	Fig. 2. Packing diagram of the title compound viewed along the b axis. Dashed lines indicate N—H···O hydrogen bonds forming infinite chains along (100). H atoms not involved in hydrogen bonding have been deleted for clarity.
	Fig. 3. Synthesis of (I).

2-(4-Bromophenyl)-N-(3,4-difluorophenyl)acetamide

Crystal data

C14H10BrF2NO	Dx = 1.722 Mg m^−3
Mr = 326.14	Cu Kα radiation, λ = 1.54184 Å
Orthorhombic, P212121	Cell parameters from 3482 reflections
a = 4.9136 (3) Å	θ = 3.1–71.3°
b = 6.0218 (4) Å	µ = 4.62 mm^−1
c = 42.514 (2) Å	T = 173 K
V = 1257.96 (13) Å^3	Block, colorless
Z = 4	0.48 × 0.32 × 0.16 mm
F(000) = 648

Data collection

Agilent Xcalibur (Eos, Gemini) diffractometer	2402 independent reflections
Radiation source: Enhance (Cu) X-ray Source	2388 reflections with I > 2σ(I)
Detector resolution: 16.1500 pixels mm^-1	Rint = 0.036
ω scans	θmax = 71.4°, θmin = 4.2°
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012)	h = −5→4
Tmin = 0.257, Tmax = 1.000	k = −7→7
6592 measured reflections	l = −51→52

Refinement

Refinement on F^2	H-atom parameters constrained
Least-squares matrix: full	w = 1/[σ^2(Fo^2) + (0.0518P)^2 + 2.6477P] where P = (Fo^2 + 2Fc^2)/3
R[F^2 > 2σ(F^2)] = 0.041	(Δ/σ)max = 0.001
wR(F^2) = 0.106	Δρmax = 0.87 e Å^−3
S = 1.15	Δρmin = −0.59 e Å^−3
2402 reflections	Extinction correction: SHELXL2012 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
173 parameters	Extinction coefficient: 0.0034 (5)
0 restraints	Absolute structure: Flack x determined using 915 quotients [(I^+)-(I^-)]/[(I^+)+(I^-)] (Parsons & Flack, 2004)
Hydrogen site location: inferred from neighbouring sites	Absolute structure parameter: −0.01 (2)

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Br1	0.05444 (13)	1.14849 (10)	0.52705 (2)	0.0255 (2)
F1	0.8291 (12)	−0.2536 (11)	0.73852 (13)	0.0682 (16)
F2	1.2315 (12)	−0.3056 (8)	0.69684 (13)	0.0577 (14)
O1	0.5535 (9)	0.4454 (8)	0.63179 (10)	0.0308 (9)
N1	0.9924 (9)	0.3661 (9)	0.64466 (11)	0.0243 (11)
H1	1.1630	0.3988	0.6404	0.029*
C1	0.7964 (12)	0.4695 (10)	0.62744 (13)	0.0203 (12)
C2	0.9134 (13)	0.6097 (10)	0.60058 (15)	0.0283 (13)
H2A	1.0489	0.7148	0.6093	0.034*
H2B	1.0088	0.5109	0.5856	0.034*
C3	0.6979 (12)	0.7387 (11)	0.58317 (14)	0.0222 (12)
C4	0.5905 (13)	0.6561 (11)	0.55519 (14)	0.0274 (12)
H4	0.6491	0.5161	0.5474	0.033*
C5	0.3960 (12)	0.7791 (10)	0.53850 (14)	0.0231 (13)
H5	0.3216	0.7238	0.5194	0.028*
C6	0.3155 (12)	0.9796 (10)	0.55018 (13)	0.0206 (11)
C7	0.4148 (13)	1.0645 (10)	0.57804 (14)	0.0235 (12)
H7	0.3531	1.2035	0.5858	0.028*
C8	0.6072 (12)	0.9412 (11)	0.59439 (13)	0.0255 (13)
H8	0.6779	0.9970	0.6136	0.031*
C9	0.9424 (13)	0.2099 (10)	0.66883 (13)	0.0247 (12)
C10	1.1086 (13)	0.0238 (12)	0.67050 (15)	0.0300 (14)
H10	1.2496	0.0018	0.6555	0.036*
C11	1.0656 (16)	−0.1289 (11)	0.69426 (16)	0.0365 (15)
C12	0.8674 (15)	−0.0986 (14)	0.71582 (17)	0.0427 (19)
C13	0.7024 (15)	0.0831 (15)	0.71475 (16)	0.0415 (19)
H13	0.5641	0.1022	0.7301	0.050*
C14	0.7366 (14)	0.2408 (13)	0.69109 (15)	0.0305 (14)
H14	0.6217	0.3675	0.6901	0.037*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.0229 (3)	0.0270 (3)	0.0266 (3)	0.0051 (2)	0.0000 (2)	0.0054 (2)
F1	0.062 (3)	0.089 (4)	0.054 (3)	−0.020 (3)	−0.005 (3)	0.045 (3)
F2	0.063 (3)	0.045 (3)	0.065 (3)	0.010 (2)	−0.009 (3)	0.009 (2)
O1	0.015 (2)	0.045 (2)	0.032 (2)	0.003 (2)	0.0007 (18)	0.0076 (19)
N1	0.007 (2)	0.037 (3)	0.029 (2)	−0.001 (2)	0.0003 (16)	0.006 (2)
C1	0.011 (3)	0.025 (3)	0.025 (3)	0.001 (2)	0.000 (2)	−0.002 (2)
C2	0.016 (3)	0.031 (3)	0.038 (3)	−0.005 (3)	0.005 (2)	0.009 (2)
C3	0.012 (3)	0.030 (3)	0.024 (3)	0.002 (2)	0.004 (2)	0.006 (2)
C4	0.026 (3)	0.024 (3)	0.032 (3)	0.009 (3)	0.005 (2)	−0.002 (2)
C5	0.023 (3)	0.022 (3)	0.024 (3)	0.004 (2)	0.000 (2)	−0.002 (2)
C6	0.013 (3)	0.024 (3)	0.024 (3)	0.002 (2)	−0.003 (2)	0.007 (2)
C7	0.021 (3)	0.023 (3)	0.027 (3)	0.006 (3)	0.002 (2)	−0.005 (2)
C8	0.024 (3)	0.030 (3)	0.022 (3)	−0.003 (3)	0.001 (2)	−0.002 (2)
C9	0.017 (3)	0.033 (3)	0.024 (3)	−0.010 (3)	−0.006 (2)	0.003 (2)
C10	0.022 (3)	0.040 (4)	0.027 (3)	0.003 (3)	0.000 (2)	0.003 (3)
C11	0.038 (4)	0.031 (3)	0.041 (3)	−0.006 (4)	−0.013 (3)	0.006 (3)
C12	0.036 (4)	0.057 (5)	0.035 (3)	−0.016 (3)	−0.012 (3)	0.020 (3)
C13	0.025 (4)	0.069 (6)	0.029 (3)	−0.009 (4)	0.001 (3)	0.007 (3)
C14	0.024 (3)	0.042 (4)	0.025 (3)	0.002 (3)	0.001 (2)	0.003 (3)

Geometric parameters (Å, º)

Br1—C6	1.909 (6)	C5—C6	1.364 (9)
F1—C12	1.356 (8)	C5—H5	0.9500
F2—C11	1.345 (9)	C6—C7	1.379 (8)
O1—C1	1.217 (8)	C7—C8	1.389 (9)
N1—C1	1.360 (7)	C7—H7	0.9500
N1—C9	1.414 (8)	C8—H8	0.9500
N1—H1	0.8800	C9—C10	1.388 (10)
C1—C2	1.532 (8)	C9—C14	1.398 (9)
C2—C3	1.508 (8)	C10—C11	1.382 (9)
C2—H2A	0.9900	C10—H10	0.9500
C2—H2B	0.9900	C11—C12	1.350 (11)
C3—C8	1.383 (9)	C12—C13	1.362 (12)
C3—C4	1.393 (9)	C13—C14	1.394 (10)
C4—C5	1.402 (8)	C13—H13	0.9500
C4—H4	0.9500	C14—H14	0.9500
C1—N1—C9	124.9 (5)	C6—C7—C8	118.2 (5)
C1—N1—H1	117.5	C6—C7—H7	120.9
C9—N1—H1	117.5	C8—C7—H7	120.9
O1—C1—N1	123.9 (6)	C3—C8—C7	121.2 (6)
O1—C1—C2	123.2 (6)	C3—C8—H8	119.4
N1—C1—C2	112.8 (5)	C7—C8—H8	119.4
C3—C2—C1	112.7 (5)	C10—C9—C14	119.9 (6)
C3—C2—H2A	109.0	C10—C9—N1	118.2 (6)
C1—C2—H2A	109.0	C14—C9—N1	122.0 (6)
C3—C2—H2B	109.0	C11—C10—C9	119.0 (6)
C1—C2—H2B	109.0	C11—C10—H10	120.5
H2A—C2—H2B	107.8	C9—C10—H10	120.5
C8—C3—C4	119.2 (6)	F2—C11—C12	119.3 (6)
C8—C3—C2	120.7 (6)	F2—C11—C10	119.6 (7)
C4—C3—C2	120.1 (6)	C12—C11—C10	121.1 (7)
C3—C4—C5	120.1 (6)	C11—C12—F1	119.4 (8)
C3—C4—H4	119.9	C11—C12—C13	121.0 (7)
C5—C4—H4	119.9	F1—C12—C13	119.6 (8)
C6—C5—C4	118.8 (6)	C12—C13—C14	120.0 (7)
C6—C5—H5	120.6	C12—C13—H13	120.0
C4—C5—H5	120.6	C14—C13—H13	120.0
C5—C6—C7	122.5 (6)	C13—C14—C9	119.0 (7)
C5—C6—Br1	118.6 (4)	C13—C14—H14	120.5
C7—C6—Br1	118.9 (5)	C9—C14—H14	120.5
C9—N1—C1—O1	3.0 (10)	C1—N1—C9—C10	138.7 (6)
C9—N1—C1—C2	−173.6 (5)	C1—N1—C9—C14	−42.7 (9)
O1—C1—C2—C3	8.0 (9)	C14—C9—C10—C11	0.3 (9)
N1—C1—C2—C3	−175.4 (5)	N1—C9—C10—C11	179.0 (6)
C1—C2—C3—C8	83.5 (7)	C9—C10—C11—F2	−177.5 (6)
C1—C2—C3—C4	−97.5 (7)	C9—C10—C11—C12	−0.6 (10)
C8—C3—C4—C5	0.9 (9)	F2—C11—C12—F1	−3.9 (11)
C2—C3—C4—C5	−178.1 (5)	C10—C11—C12—F1	179.1 (6)
C3—C4—C5—C6	0.1 (9)	F2—C11—C12—C13	177.3 (7)
C4—C5—C6—C7	−1.1 (9)	C10—C11—C12—C13	0.3 (11)
C4—C5—C6—Br1	179.1 (5)	C11—C12—C13—C14	0.1 (11)
C5—C6—C7—C8	1.1 (9)	F1—C12—C13—C14	−178.6 (7)
Br1—C6—C7—C8	−179.1 (5)	C12—C13—C14—C9	−0.4 (11)
C4—C3—C8—C7	−1.0 (9)	C10—C9—C14—C13	0.1 (10)
C2—C3—C8—C7	178.0 (6)	N1—C9—C14—C13	−178.5 (6)
C6—C7—C8—C3	0.0 (9)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1^i	0.88	1.97	2.851 (7)	175
C7—H7···O1^ii	0.95	2.63	3.309 (8)	129
C13—H13···F1^iii	0.95	2.50	3.426 (9)	164

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