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

Praveen, A.S.; Yathirajan, H.S.; Jasinski, J.P.; Keeley, A.C.; Narayana, B.; Sarojini, B.K.

doi:10.1107/S1600536813012865

organic compounds

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ISSN: 2056-9890

Volume 69| Part 6| June 2013| Pages o900-o901

doi:10.1107/S1600536813012865

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

A.S. Praveen,^a H. S. Yathirajan,^a Jerry P. Jasinski,^b ^* Amanda C. Keeley,^b B. Narayana ^c and B. K. Sarojini ^d

^aDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India, ^bDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA, ^cDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri 574 199, India, and ^dDepartment of Chemistry, P.A.College of Engineering, Nadupadavu, Mangalore 574 153, India
^*Correspondence e-mail: jjasinski@keene.edu

(Received 6 May 2013; accepted 9 May 2013; online 18 May 2013)

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].

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 ).

Experimental

Crystal data

C₁₄H₁₀BrF₂NO
M_r = 326.14
Orthorhombic, P 2₁ 2₁ 2₁
a = 4.9136 (3) Å
b = 6.0218 (4) Å
c = 42.514 (2) Å
V = 1257.96 (13) Å³
Z = 4
Cu Kα radiation
μ = 4.62 mm⁻¹
T = 173 K
0.48 × 0.32 × 0.16 mm

Data collection

Agilent Xcalibur (Eos, Gemini) diffractometer
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012 ) T_min = 0.257, T_max = 1.000
6592 measured reflections
2402 independent reflections
2388 reflections with I > 2σ(I)
R_int = 0.036

Refinement

R[F² > 2σ(F²)] = 0.041
wR(F²) = 0.106
S = 1.15
2402 reflections
173 parameters
H-atom parameters constrained
Δρ_max = 0.87 e Å⁻³
Δρ_min = −0.59 e Å⁻³
Absolute structure: Flack x determined using 915 quotients [(I⁺)−(I⁻)]/[(I⁺)+(I⁻)] (Parsons & Flack, 2004 )
Flack parameter: −0.01 (2)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O1ⁱ	0.88	1.97	2.851 (7)	175
C7—H7⋯O1ⁱⁱ	0.95	2.63	3.309 (8)	129
C13—H13⋯F1ⁱⁱⁱ	0.95	2.50	3.426 (9)	164
Symmetry codes: (i) x+1, y, z; (ii) x, y+1, z; (iii) $[-x+1, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO; 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536813012865/hg5313sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813012865/hg5313Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813012865/hg5313Isup3.cml

checkCIF report

Comment top

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 top

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).

Experimental top

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).

Computing details top

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 top

	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 top

Crystal data top

C₁₄H₁₀BrF₂NO	D_x = 1.722 Mg m⁻³
M_r = 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) Å³	Block, colorless
Z = 4	0.48 × 0.32 × 0.16 mm
F(000) = 648

Data collection top

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	R_int = 0.036
ω scans	θ_max = 71.4°, θ_min = 4.2°
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012)	h = −5→4
T_min = 0.257, T_max = 1.000	k = −7→7
6592 measured reflections	l = −51→52

Refinement top

Refinement on F²	H-atom parameters constrained
Least-squares matrix: full	w = 1/[σ²(F_o²) + (0.0518P)² + 2.6477P] where P = (F_o² + 2F_c²)/3
R[F² > 2σ(F²)] = 0.041	(Δ/σ)_max = 0.001
wR(F²) = 0.106	Δρ_max = 0.87 e Å⁻³
S = 1.15	Δρ_min = −0.59 e Å⁻³
2402 reflections	Extinction correction: SHELXL2012 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/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)

Crystal data top

C₁₄H₁₀BrF₂NO	V = 1257.96 (13) Å³
M_r = 326.14	Z = 4
Orthorhombic, P2₁2₁2₁	Cu Kα radiation
a = 4.9136 (3) Å	µ = 4.62 mm⁻¹
b = 6.0218 (4) Å	T = 173 K
c = 42.514 (2) Å	0.48 × 0.32 × 0.16 mm

Data collection top

Agilent Xcalibur (Eos, Gemini) diffractometer	2402 independent reflections
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012)	2388 reflections with I > 2σ(I)
T_min = 0.257, T_max = 1.000	R_int = 0.036
6592 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.041	H-atom parameters constrained
wR(F²) = 0.106	Δρ_max = 0.87 e Å⁻³
S = 1.15	Δρ_min = −0.59 e Å⁻³
2402 reflections	Absolute structure: Flack x determined using 915 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons & Flack, 2004)
173 parameters	Absolute structure parameter: −0.01 (2)
0 restraints

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
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 (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
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) top

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) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱ	0.88	1.97	2.851 (7)	175
C7—H7···O1ⁱⁱ	0.95	2.63	3.309 (8)	129
C13—H13···F1ⁱⁱⁱ	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.

Experimental details

Crystal data
Chemical formula	C₁₄H₁₀BrF₂NO
M_r	326.14
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	173
a, b, c (Å)	4.9136 (3), 6.0218 (4), 42.514 (2)
V (Å³)	1257.96 (13)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	4.62
Crystal size (mm)	0.48 × 0.32 × 0.16

Data collection
Diffractometer	Agilent Xcalibur (Eos, Gemini) diffractometer
Absorption correction	Multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012)
T_min, T_max	0.257, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	6592, 2402, 2388
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.615

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.041, 0.106, 1.15
No. of reflections	2402
No. of parameters	173
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.87, −0.59
Absolute structure	Flack x determined using 915 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons & Flack, 2004)
Absolute structure parameter	−0.01 (2)

Computer programs: CrysAlis PRO (Agilent, 2012), CrysAlis RED (Agilent, 2012), SHELXS97 (Sheldrick, 2008), SHELXL2012 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱ	0.88	1.97	2.851 (7)	175.1
C7—H7···O1ⁱⁱ	0.95	2.63	3.309 (8)	128.9
C13—H13···F1ⁱⁱⁱ	0.95	2.50	3.426 (9)	163.9

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

Acknowledgements

ASP thanks the University of Mysore for research facilities. BN thanks the UGC for financial assistance through a BSR one-time grant for the purchase of chemicals. JPJ acknowledges the NSF–MRI program (grant No. CHE-1039027) for funds to purchase the X-ray diffractometer.

References

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